BMLC 101
Unit IV
Digestive System
By
Sujoy Tontubay, Assistant Professor (Medical Lab Technology), iLEAD, Kolkata.
B.Sc. (University of Calcutta), M.Sc. in Biomedical Laboratory Science(V.U), Post Graduate
Diploma in Epidemiology and Public Health(V.U)
Former Guest Lecturer (Medical Laboratory technology) in Guru Nanak Institute of
Pharmaceuticals Science and Technology (G.N.I.P.S.T), Lokenath Educational Institute.
Digestive system of Humans
• The digestive tract of
humans starts with the
mouth and ends with
the anus. It includes
different structures such
as the mouth,
oesophagus, pancreas,
stomach, small intestine,
large intestine, liver, gall
bladder, and anus.
Parts of the Human Digestive System
• The digestive system of the human body comprises a group of organs that work together in
converting food into energy and other basic nutrients to power the body. The food we take in is
digested and utilized by our body, and the unused parts of the food are defecated.
• The digestive system of the human body is the sum of the gastrointestinal tract (GIT; also called
alimentary canal) and accessory organs (tongue, liver, pancreas, etc.). These two parts together
help in the digestion process.
• The alimentary canal is the long tube through which the food that we eat is passed. It begins at
the mouth (buccal or oral cavity), passes through the pharynx, oesophagus or food pipe, stomach,
small intestines, large intestines, rectum and finally ends at the anus. The food particles gradually
get digested as they travel through various compartments of the alimentary canal.
• Accessory organs are organs which participate in the digestion process but are not actually a part
of GIT. They stimulate the digestion by releasing certain enzymes that help in breaking down the
food.
• Let us have a detailed look at the digestive system of the human body, along with its parts and
functions:
• Mouth
• Food starts its journey from the mouth or the oral cavity. There are many other
organs that contribute to the digestion process, including teeth, salivary glands,
and tongue. Teeth are designed for grinding food particles into small pieces and
are moistened with saliva before the tongue pushes the food into the pharynx.
• Pharynx
• A fibromuscular y-shaped tube attached to the terminal end of the mouth. It is
mainly involved in the passage of chewed/crushed food from the mouth
through the oesophagus. It also has a major part in the respiratory system, as
air travels through the pharynx from the nasal cavity on its way to the lungs.
• Oesophagus
• This is a muscular tube that connects the pharynx, which is a part of an upper
section of the gastrointestinal tract. It supplies swallowed food along with its
length.
• Stomach
• It serves as a muscular bag which is situated towards the left side of the abdominal cavity,
beneath the diaphragm. This vital organ acts as a storage for the food and provides enough
time to digest meals. The stomach also produces digestive enzymes and hydrochloric acid
that maintains the process of digestion.
• Mucous: It is an aqueous secretion produced by the mucous membranes. It functions by
protecting the stomach lining and gastric pits from the acid, which is produced by the glands
to destroy the bacteria that entered along with the food particles.
• Digestive enzymes: They are the group of enzymes which functions by breaking down
polymeric macromolecules like biopolymers into their smaller and simpler substances.
• Hydrochloric acid: It is the digestive fluid formed by the stomach during the process of
digestion. It functions by destroying harmful microorganisms present in the food particles.
• Small Intestine
• The small intestine is a thin, long tube of about 10 feet long and a part of the lower
gastrointestinal tract. It is present just behind the stomach and acquires a maximum area of
the abdominal cavity. The complete small intestine is coiled and the inner surface consists of
folds and ridges.
• Large Intestine
• This is a thick, long tube measuring around 5 feet in length. It is present just beneath the stomach and
wraps over the superior and lateral edges of the small intestine. It absorbs water and consists of
bacteria (symbiotic) that support the breakdown of wastes to fetch small nutrients.
• Rectum
• Waste products are passed into the end of the large intestine called the rectum and eliminated out of
the body as a solid matter called stool. It is stored in the rectum as semi-solid faeces which later exits
from the body through the anal canal through the process of defecation.
• Accessory Organs
• Pancreas
• It is a large gland present just behind the stomach. It is short with its anterior connected to the
duodenum and posterior pointing towards the left part of the abdominal cavity. The pancreas releases
digestive enzymes to complete the process of chemical digestion.
• Liver
• The liver is a roughly triangular, reddish-brown accessory organ of the digestive system located to the
right of the stomach. It produces bile, which helps in the digestion of fat in the small intestine. The bile
is stored and recycled in the gallbladder. It is a small, pear-shaped organ which is located just next to
the liver.
Digestion Process
• The process of digestion begins from the mouth and ends in the small intestine – the large intestines’
main function is to absorb the remaining water from the undigested food and enable bacterial
fermentation of materials that can no longer be digested.
• The alimentary canal or the gastrointestinal tract is a series of hollow organs and tubes that begins
from the mouth cavity and continues into the pharynx, through the stomach, small intestines, large
intestines, and finally ending at the anus. Food particles gradually get digested as they travel through
various compartments of the gastrointestinal tract.
• The digestion process takes place in the following steps.
• Ingestion
• The very first step involves mastication (chewing). The salivary glands, along with the tongue, helps to
moisten and lubricate food, before being pushed down into the food pipe.
• Mixing and Movement
• It involves the process of lubricating and manipulating food and pushing it down the food through
the food pipe (using peristalsis), and into the stomach.
• Secretion
• The stomach, small intestine, liver, and pancreas secrete enzymes and acids to aid the
process of digestion. It functions by breaking down food particles into simple components
and easily absorbable components.
• Digestion
• The process of converting complex food particles into simpler substances in the presence
of enzymes and acids secreted by different digestive organs.
• Absorption
• This process begins in the small intestine where most of the nutrients and minerals are
absorbed. The excess water in the indigestible matter is absorbed by the large intestines.
• Excretion
• The process of removing indigestible substances and waste by-products from the body
through the process of defecation.
• In a nutshell, the digestion process consists of the six following steps:
• Ingestion Mixing and Movement Secretion Digestion Absorption Excretion
⇒ ⇒ ⇒ ⇒ ⇒
Gastrointestinal Tract Definition
“Gastrointestinal tract is the part of an organ system in humans and other
animals that take in food, digest it, absorb nutrients and expel it out in the
form of feces.”
allied health BMLC 101 DIGESTIVE SYSTEM.pptx
allied health BMLC 101 DIGESTIVE SYSTEM.pptx
Gastrointestinal Tract Anatomy
• The gastrointestinal tract in humans begins at the mouth,
continuing through the esophagus, stomach, and small and
large intestines. The GI tract is about 9 meters in length.
• There are many supporting organs, such as the liver, which
helps by secreting enzymes that are necessary for the
digestion of food.
• The human GI tract can be divided into two halves, namely:
• Upper GI tract
• Lower GI tract
Upper Gastrointestinal Tract
• The upper GI consists of the following organs:
• Mouth
• It includes the teeth, tongue, and buccal mucous membranes containing the ends of the
salivary glands that continue with the soft palate, floor of the mouth, and underside of the
tongue. Mouth functions by chewing the food, constantly by the muscular action of the
tongue, cheeks, and teeth through the lower jaw and upper jaw.
• Pharynx
• The pharynx is enclosed in the neck and functions as part of both the digestive system and
the respiratory system. It protects the food from entering the trachea and lungs.
• esophagus
• A muscular tube-like structure that functions by carrying food to the stomach. Once the
chewed food reaches the esophagus from the mouth, the action of swallowing becomes
involuntary and is controlled by the esophagus.
• Stomach
• This is where most of the digestion takes place. The stomach is a J-shaped bag-like organ
that stores the food temporarily, breaks it down, mixes and churns it with enzymes and
other digestive fluids and finally, passes it along to the small intestine.
Lower Gastrointestinal Tract
• The lower GI consists of the following organs:
• Small Intestine
• The small intestine is a coiled thin tube, about 6 meters in length, where most
of the absorption of nutrients takes place. Food is mixed with enzymes from
the liver and the pancreas in the small intestine. The surfaces of the small
intestine function by absorbing the nutrients from the food into the
bloodstream, which carries them to the rest of the body.
• Large Intestine
• The large intestine, also known as the Colon, is a thick tubular organ wrapped
around the small intestine. Its primary function is to process the waste
products and absorb any remaining nutrients and water back into the system.
The remaining waste is then sent to the rectum and discharged from the body
as stool.
Digestion:
1.Before the body can use the food, it has to be first absorbed by the bloodstream.
2.This is done by breaking the large, insoluble food molecules into smaller, soluble
ones by the process of digestion, which is performed by the digestive system.
3.Digestion is a mechanical and chemical breakdown of food into small organic
fragments.
4.Mechanical digestion referred to the physical breakdown of large pieces of food
into smaller pieces that can subsequently be accessed by digestive enzymes.
5.In chemical digestion, these enzymes break down food into small molecules that
the body can use.
6.Relevant organs are the mouth and teeth, alimentary canal, stomach, and
duodenum.
Absorption:
1.A simple product of digestion is small enough to be absorbed by the
epithelial cells of the intestinal villi.
2.Each day the alimentary canal processes up to 10 liters of food, liquids,
and GI secretions, also less than one liter enters the large intestine.
3.Almost all ingested food, 80% of electrolytes, and 90% of water are
absorbed in the small intestine.
4.Although the entire small intestines are involved in the absorption of
water and lipids, most absorption of carbohydrates and proteins occurs in
the jejunum.
5.The small intestine is very highly efficient at this, absorbing
monosaccharides at an estimated rate of 120 grams per hour.
6.Especially, bile salts and vitamin B12 are absorbed in the terminal ileum.
Assimilation:
1.It is the movement of the digested food molecules into the
cells of the body from where they are used.
2.The liver is important in assimilation
3.For example, glucose is used in respiration to provide
energy, and also amino acids are used to build new proteins.
4.The fate of the absorbed food glucose for energy
production, amino acids for building up body materials, and
fats for energy reserve.
Gastrointestinal hormones
• Gastrin
• Gastrin is produced by G cells of the antral glands of the duodenum
and small intestine
• Actions: ◦ Stimulation of gastric acid secretion ◦ motility and Trophic
effects on parietal cell mass
• secretion of hydrochloric acid (HCl) into the stomach.
• pH > 3.0
• also known as the CCKB receptor
Cholecystokinin (CCK)
• Cholecystokinin (CCK) is produced by I cells of the duodenum and upper jejunum with 115
amino acid prepropeptide.
• Specificity determined by a sulfated tyrosine
• As most important function is considered to be the stimulation of the secretion of
pancreatic juice, induction of the contractions of the gallbladder and relaxation of Oddi’s
sphincter
• Regulation ◦ Fat and protein digestive products, especially Phe and Trp
• CCKA receptor is present in the gallbladder and pancreas.
• CCKB (gastrin) receptor is expressed in the brain and gastric fundus
Actions:
◦ Indirectly stimulates pancreatic exocrine secretion
◦ Stimulates gallbladder contraction
◦ Inhibits gastric emptying
◦ Trophic effects on the pancreas
◦ Influences sensation of satiety
• Secretin
• Structure: 27 amino acids
• Secretin is produced by S cells of the duodenum and jejunum
• It stimulates the secretion of fluid and bicarbonates in pancreas, large
intestine, and secretion of pepsin in the stomach.
• It inhibits the secretion of HCl, motility of the stomach and the tonus
of the lower oesophageal sphincter.
• Stimulation of pancreatic water and bicarbonate secretion
• Secretin secretion is stimulated by
– acidification of the duodenum
– products of fat digestion
Somatostatin
• Somatostatin (SMS) – is produced by endocrine and paracrine D cells
in the entire intestine
• It inhibits the motility in GIT and exocrine and endocrine secretions.
• Splanchnic vasoconstriction
Clinical Applications
• Secretory diarrhea
• Pancreatic secretions
• Gastrointestinal hemorrhage (variceal bleeding)
Motilin
• 22 amino acids
• Motilin is produced in M cells of the duodenum. It induces the
contractile activity of the stomach and intestines
• Actions: serum levels parallel that of the interdigestive motor complex
• Pharmacology: erythromycin binds to the motilin receptor and acts as
an agonist
• Used in the clinical setting to promote motility
• Our digestive system provides us with one of the essential functions of life, Nutrition, which
helps to provide us with energy and provides our body with building blocks to create new
body cells from.
• The digestive system is essentially a tube which extends from the mouth to the rectum.
• Components of the digestive system
• Food passes through the digestive system in the following order:
• Mouth
• Esophagus
• Stomach
• The small intestine
• Colon (large intestine)
• Rectum
• Through this process a number of enzymes act on the food we eat (inc liver, pancreas, gall
bladder).
• The mouth and esophagus
• In the mouth, saliva acts to start to break down carbohydrates thanks to an enzyme called
amylase. The esophagus is a tube, controlled by muscles and autonomic nerves, that helps
food to travel from the mouth to the stomach.
• The stomach
• The stomach coats the food with a mixture of acid and
digestive enzymes to help break the food down further. A
layer of mucous protects the stomach lining from being
damaged by the acid.
• The bottom of the stomach is able to contract, which helps
to speed up the process. When the food is broken down
sufficiently the stomach releases its contents into the
duodenum.
• The small intestine
• The small intestine is categorised in three parts; the duodenum
being the first, the jejunum second and the ileum the final part.
• When food enters the duodenum, the pancreas releases enzymes to
help break down fat, protein and carbohydrate The gall bladder
releases bile, which has been produced by the liver, to help further
break fats down into a form that can be absorbed by the intestines.
• The small intestine is lined with finger-like projections, called villi,
which provide a very large surface area facilitating the absorption of
nutrients, including carbohydrates, proteins and fats, into the
bloodstream.
• The small intestine contains a number of receptive cells which detect
the presence of macronutrients and secrete hormones which
instructs the pancreas on how much insulin and glucagon to release.
• The colon (large intestine)
• The final stage of the digestive system is the colon (large
intestine) which absorbs water and salts before the remains
are passed out of the rectum as faeces. The colon can also
help to absorb remaining carbohydrate and some fats.
Liver
• The liver is located in the upper right portion of the
abdomen. It is the largest gland in the human body that
performs several important functions. It is the only
organ that has the ability to regenerate efficiently.
Liver Anatomy
Structure of Liver :
• The liver is a triangular, bilobed structure consisting of a
larger right lobe and a smaller left lobe. The falciform
ligament separates the two lobes.
• A layer of fibrous tissue called Glisson’s capsule covers
the liver. This capsule is covered by the peritoneum.
This protects the liver from physical damage.
• It has two main sources of blood:
• Hepatic Portal Vein carries nutrient-rich blood from the
digestive system.
• Hepatic Artery carries oxygenated blood from the heart.
• Functions of Liver
• The important functions of the liver are mentioned below:
• Production of Bile
• Bile, which helps in the digestion and absorption of fats, vitamins and cholesterol is produced in the liver.
• Absorption of Bilirubin
• Bilirubin is formed by the breakdown of haemoglobin. The iron released is stored in the liver to make next-generation blood cells.
• Supporting Blood Clots
• Bile is responsible for the absorption of vitamin K. If bile is not produced, clotting factors will not be produced.
• Metabolization of Fats
• Bile helps in the breakdown and digestion of fats.
• Carbohydrate Metabolization
• The carbohydrates stored in the liver as glycogen are broken down into glucose and released into the blood to maintain glucose levels.
• Storage of Vitamins and Minerals
• Vitamins A, D, E, K, and B12 are stored in the liver. It also stores iron in the form of ferritin to form new red blood cells.
• Metabolization of Proteins
• Bile helps in the digestion of proteins.
• Filtering Blood
• The compounds such as hormones, alcohol, etc are filtered by the liver from the blood.
• Immunological Function
• The liver contains Kuffer cells involved in immune activity. These destroy any disease-causing agents.
• Albumin Production
• Albumin transports fatty acids and steroids to maintain correct pressure and prevent leakage of blood vessels.
• Angiotensinogen Synthesis
• This hormone is responsible for the narrowing of blood vessels which results in an increase in blood pressure.
• Regeneration of Liver
• The liver has the ability to regrow in all vertebrates. The functions of the liver are not lost during the growth process. In humans, regeneration takes 8-15 days.
• In mice, the same process takes around 5-7 days.
Spleen
• The spleen is a large, encapsulated,
bean-shaped organ that is situated on
the left side of the body below the
diaphragm. The spleen contains T and B
lymphocytes as well as many
phagocytes and is a major component
of the mononuclear phagocyte system.
Although the structure resembles that
of the large lymph nodes, the spleen
differs from a lymph node in having no
lymphatic drainage, and also in
containing large numbers of red cells.
Structure of spleen
• It is a dark purple-coloured organ, which lies in the left hypochondriae
region of the abdomen, between the fundus of the stomach and the
diaphragm.
• It varies in size and weight during the lifetime of an individual but in an
adult is usually about 12 cm long, 8cm broad and 3-4 cm thick weighing
about 200gm.
• The spleen has diaphragmatic and visceral surfaces. The diaphragmatic
surface is in contact with the inner surface of the diaphragm.
• The spleen has an outer coat of peritoneum which is firmly adherent to
the internal fibro-elastic coat or splenic capsule that dips into the
organ, forming trabeculae.
Function of Spleen
1.The main immunological function of the spleen is to filter the blood by trapping bloodborne
microbes and producing an immune response to them. It is particularly important for B cell
responses to polysaccharide antigens.
2.The spleen is formed partly by lymphatic tissue which produces T lymphocytes and B lymphocytes.
3.Due to the presence of lymphoid reticulo-endothelial tissue, the spleen is involved in producing
antibodies and antitoxin.
4.In the foetus, the spleen acts as an important haemopoitic organ.
5.It also removes damaged red blood cells and immune complexes.
6.It can act as an erythropoietic organ which acts as a reservoir of erythrocytes or a reservoir for
blood.
7.Those individuals who have had their spleens removed (splenectomized) have a greater
susceptibility to infection with encapsulated bacteria, and are at increased risk of severe malarial
infections, which indicates its major importance in immunity.
Gallbladder
• The gallbladder is a pear-shaped, hollow structure located under the liver
and on the right side of the abdomen. Its primary function is to store and
concentrate bile, a yellow-brown digestive enzyme produced by the liver.
The gallbladder is part of the biliary tract.
• The gallbladder serves as a reservoir for bile while it’s not being used for
digestion. The gallbladder’s absorbent lining concentrates the stored bile.
When food enters the small intestine, a hormone called cholecystokinin is
released, signaling the gallbladder to contract and secrete bile into the
small intestine through the common bile duct.
• The bile helps the digestive process by breaking up fats. It also drains
waste products from the liver into the duodenum, a part of the small
intestine.
Structure of the Gallbladder
• The approximate shape and size of
the gallbladder are described as pear-
like. Its average storage capacity is
between 30 to 50 milliliters (mL). The
gallbladder structure is generally
divided into three parts: the fundus,
the body, and the neck.
Gallbladder Function
• To store and concentrate bile.
• To respond to intestinal hormones (such as cholecystokinin) to empty
and refill its bile stores.
• To contribute to regulating the composition of bile (the percentage of
water, bile salts and more)
• To control the flow of bile into the small intestine.
What is Pancreas?
• Pancreas is an abdominal organ located
behind the stomach and surrounded by
spleen, liver and small intestine. It is a vital
part of the digestive system and is
responsible for regulating blood sugar levels.
• The pancreas secretes digestive enzymes
such as amylase, proteases and lipase into
the duodenum. These enzymes help in
digesting sugar, proteins and fat respectively.
Islets of Langerhans are embedded in the
pancreas that secretes hormones such as
insulin and glucagon into the blood.
Pancreas Location
• The pancreas is located in the abdomen. A part of it is placed
between the stomach and the spine. The other part finds its place in
the curve of the first section of the small intestine, known as the
duodenum.
• The head of the pancreas is on the right side of the abdomen and is
connected to the duodenum through the pancreatic duct. The tail of
the pancreas extends to the left side of the body.
Pancreas Function
• The pancreas performs the following functions:
• Exocrine Function
• The pancreas consists of exocrine glands that produce enzymes trypsin and
chymotrypsin that are essential for digestion. These enzymes contain chymotrypsin
and trypsin to digest proteins, amylase for the digestion of carbohydrates and
lipase to break down fats. These pancreatic juices are liberated into the system of
ducts and culminated in the pancreatic duct when the food enters the stomach.
• Endocrine Function
• The endocrine part of the pancreas comprises Islets of Langerhans that release
insulin and glucagon directly into the bloodstream. They help in regulating the
blood sugar levels of the body.
Structure of Pancreas
• Appearing as a pinkish-tan structure, the pancreas is a J-shaped organ and distinctly appears lobulated.
The connective tissue involved renders septation to give rise to macroscopic lobules that make up the
functional units of the exocrine pancreas.
• In adult males, this wet structure approximately weighs 100 g, in adult females 85 g while in newborns it
weighs about 5 g. The length of the adult gland is about 14 to 18 cm, width is 2 to 9 cm with a thickness
of 2 to 3 cm. The structure can be distinguished into 4 main areas – head with the uncinate process,
neck, body with tuber omentale and the tail.
• Different parts of the Pancreas
• The pancreas’ head is seen in the loop of the duodenum as it leaves the stomach
• The body of the pancreas is seen posterior to the distal part of the stomach between the neck and the
tail
• The part of the pancreas seen anterior to the aorta is kind of thin compared to the nearby parts of the
head and the body of the pancreas. This area is at times assigned as the neck and indicates the junction
of the body and head
• The common bile duct passes through the pancreas’ head and joins the main pancreatic duct, seen near
the duodenum. The part which lies closest to the liver in a groove on the dorsal part of the head
Jaundice
• Adults and children with jaundice may notice a yellowish tinge to
their skin, mucous membranes, and the whites of the eyes. It can
happen with various health conditions and usually indicates a
problem with the liver or bile ducts.
Causes and risk factors
• According to the American Family Physician (AAFP), jaundice is the yellowing of the skin, mucous membranes, and the
whites of the eyes that occurs when the body does not process bilirubin as it should.
• Bilirubin levels increase as the red blood cells naturally break down. Typically, the liver filters this waste material out of
the bloodstream and turns it into a new form called conjugated bilirubin. The new form then exits the body in a person’s
stool.
• If there is too much bilirubin for the liver to process, it can build up in the body. This is known as hyperbilirubinemia, and
it causes the yellow color in the skin and eyes.
• Jaundice typically occurs due to an underlying disorder that either causes the production of too much bilirubin or
prevents the liver from eliminating it.
• Some possible underlying conditions and causes of jaundice include:
• side effects of certain medications
• gallstone disease
• excessive alcohol consumption
• gallbladder or pancreatic cancer
• cirrhosis, which is a disease that causes scar tissue to replace healthy tissue in the liver
• hepatitis or other liver infections
• hemolytic anemia
Cirrhosis
• Cirrhosis of the liver is permanent scarring that damages your liver and
interferes with its functioning. It can lead to liver failure. Cirrhosis is the
result of persistent liver damage over many years. Alcohol and drugs,
viruses and metabolic factors are the most common causes.
• Cirrhosis of the liver is late stage liver disease, in which
healthy liver tissue has been gradually replaced with scar tissue. This is
a result of long-term, chronic hepatitis. Hepatitis is inflammation in
your liver, which has many causes. When inflammation is ongoing, your
liver attempts to repair itself by scarring. But too much scar tissue
prevents your liver from working properly. The end stage is chronic liver
failure.
What are the first signs of cirrhosis of
the liver?
Early signs and symptoms of cirrhosis
may include:
•Nausea or loss of appetite.
•Feeling weak or tired (fatigue).
•Feeling generally ill (malaise).
•Upper abdominal pain (especially on
the right).
•Visible blood vessels that look like
spiders (spider angiomas).
•Redness on the palms of your hands
(palmar erythema).
What are symptoms of advancing cirrhosis?
• Recognizable symptoms of cirrhosis fall into two categories: symptoms related to declining liver function, and symptoms
related to portal hypertension. Symptoms of stalled bile flow, like jaundice, are common indicators of declining liver function.
Symptoms of portal hypertension indicate cirrhosis specifically. It’s scar tissue in your liver that compresses your portal vein.
• Cirrhosis symptoms related to declining liver function include:
• Jaundice (yellow tint to your skin and eyes).
• Pruritus (itchy skin, but with no visible rash).
• Dark-colored pee and light-colored poop.
• Digestive difficulties, especially with fats.
• Small yellow bumps of fat deposits on your skin or eyelids.
• Unexplained weight loss and muscle loss.
• Hepatic encephalopathy (confusion, disorientation, mood changes).
• Motor dysfunction (twitching, tremors or lapses in muscle control).
• Disruptions to your menstrual cycle.
• Enlarged male breast tissue and shrunken testes in people AMAB.
• Cirrhosis symptoms related to portal hypertension include:
• Swelling in your abdomen (ascites).
• Swelling in your hands, feet, legs and/or face (edema).
• Easy bleeding and bruising (coagulopathy)
What causes cirrhosis of the liver?
• Cirrhosis is a gradual scarring process that’s triggered by chronic inflammation in your
liver. Any chronic liver disease that causes chronic hepatitis can lead to cirrhosis. The
most common causes include:
• Alcohol-induced hepatitis. This is chronic liver damage from chronic heavy alcohol use.
Alcohol may be the most well-known cause of liver cirrhosis, but nonalcoholic causes are
also common.
• Non-alcohol-related steatohepatitis. This is chronic damage from excess fat storage in
your liver. It’s related to metabolic factors like high blood lipids, blood sugar and blood
pressure.
• Chronic hepatitis C infection. Hepatitis C is a viral infection that becomes chronic in most
people. It’s now curable with antivirals, but many people don’t realize they have it.
• Chronic hepatitis B infection. Hepatitis B is a viral infection that may become chronic in a
minority of people. If it does, you’ll have it for life. It’s treatable, but not curable.
Pancreatitis
• Pancreatitis is inflammation of the pancreas. Inflammation is immune
system activity that can cause swelling, pain, and changes in how an
organ or tissues work.
• The pancreas is a long, flat gland that's tucked behind the stomach. The
pancreas helps the body digest food and regulates blood sugars.
• Pancreatitis can be an acute condition. This means it appears suddenly
and generally lasts a short time. Chronic pancreatitis is a long-term
condition. The damage to the pancreas can get worse over time.
• Acute pancreatitis may improve on its own. More-serious disease
requires treatment in a hospital and can cause life-threatening
complications.
Symptoms
• Symptoms of pancreatitis may vary. Acute pancreatitis
symptoms may include:
• Pain in the upper belly.
• Pain in the upper belly that radiates to the back.
• Tenderness when touching the belly.
• Fever.
• Rapid pulse.
• Upset stomach.
• Vomiting.
Causes
• The pancreas has two major roles. It produces insulin, which helps the body manage and use sugars.
• The pancreas also produces dietary juices, called enzymes, that help with digestion. The pancreas makes
and stores "turned off" versions of the enzymes. After the pancreas sends the enzymes into the small
intestine, they are "turned on" and break down proteins in the small intestine.
• If the enzymes are turned on too soon, they can start acting like digestive juices inside the pancreas. The
action can irritate, damage or destroy cells. This problem, in turn, leads to immune system responses that
cause swelling and other events that affect how the pancreas works.
• Several conditions can lead to acute pancreatitis, including:
• Blockage in the bile duct caused by gallstones.
• Heavy alcohol use.
• Certain medicines.
• High triglyceride levels in the blood.
• High calcium levels in the blood.
• Pancreas cancer.
• Injuries from trauma or surgery.

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allied health BMLC 101 DIGESTIVE SYSTEM.pptx

  • 1. BMLC 101 Unit IV Digestive System By Sujoy Tontubay, Assistant Professor (Medical Lab Technology), iLEAD, Kolkata. B.Sc. (University of Calcutta), M.Sc. in Biomedical Laboratory Science(V.U), Post Graduate Diploma in Epidemiology and Public Health(V.U) Former Guest Lecturer (Medical Laboratory technology) in Guru Nanak Institute of Pharmaceuticals Science and Technology (G.N.I.P.S.T), Lokenath Educational Institute.
  • 2. Digestive system of Humans • The digestive tract of humans starts with the mouth and ends with the anus. It includes different structures such as the mouth, oesophagus, pancreas, stomach, small intestine, large intestine, liver, gall bladder, and anus.
  • 3. Parts of the Human Digestive System • The digestive system of the human body comprises a group of organs that work together in converting food into energy and other basic nutrients to power the body. The food we take in is digested and utilized by our body, and the unused parts of the food are defecated. • The digestive system of the human body is the sum of the gastrointestinal tract (GIT; also called alimentary canal) and accessory organs (tongue, liver, pancreas, etc.). These two parts together help in the digestion process. • The alimentary canal is the long tube through which the food that we eat is passed. It begins at the mouth (buccal or oral cavity), passes through the pharynx, oesophagus or food pipe, stomach, small intestines, large intestines, rectum and finally ends at the anus. The food particles gradually get digested as they travel through various compartments of the alimentary canal. • Accessory organs are organs which participate in the digestion process but are not actually a part of GIT. They stimulate the digestion by releasing certain enzymes that help in breaking down the food. • Let us have a detailed look at the digestive system of the human body, along with its parts and functions:
  • 4. • Mouth • Food starts its journey from the mouth or the oral cavity. There are many other organs that contribute to the digestion process, including teeth, salivary glands, and tongue. Teeth are designed for grinding food particles into small pieces and are moistened with saliva before the tongue pushes the food into the pharynx. • Pharynx • A fibromuscular y-shaped tube attached to the terminal end of the mouth. It is mainly involved in the passage of chewed/crushed food from the mouth through the oesophagus. It also has a major part in the respiratory system, as air travels through the pharynx from the nasal cavity on its way to the lungs. • Oesophagus • This is a muscular tube that connects the pharynx, which is a part of an upper section of the gastrointestinal tract. It supplies swallowed food along with its length.
  • 5. • Stomach • It serves as a muscular bag which is situated towards the left side of the abdominal cavity, beneath the diaphragm. This vital organ acts as a storage for the food and provides enough time to digest meals. The stomach also produces digestive enzymes and hydrochloric acid that maintains the process of digestion. • Mucous: It is an aqueous secretion produced by the mucous membranes. It functions by protecting the stomach lining and gastric pits from the acid, which is produced by the glands to destroy the bacteria that entered along with the food particles. • Digestive enzymes: They are the group of enzymes which functions by breaking down polymeric macromolecules like biopolymers into their smaller and simpler substances. • Hydrochloric acid: It is the digestive fluid formed by the stomach during the process of digestion. It functions by destroying harmful microorganisms present in the food particles. • Small Intestine • The small intestine is a thin, long tube of about 10 feet long and a part of the lower gastrointestinal tract. It is present just behind the stomach and acquires a maximum area of the abdominal cavity. The complete small intestine is coiled and the inner surface consists of folds and ridges.
  • 6. • Large Intestine • This is a thick, long tube measuring around 5 feet in length. It is present just beneath the stomach and wraps over the superior and lateral edges of the small intestine. It absorbs water and consists of bacteria (symbiotic) that support the breakdown of wastes to fetch small nutrients. • Rectum • Waste products are passed into the end of the large intestine called the rectum and eliminated out of the body as a solid matter called stool. It is stored in the rectum as semi-solid faeces which later exits from the body through the anal canal through the process of defecation. • Accessory Organs • Pancreas • It is a large gland present just behind the stomach. It is short with its anterior connected to the duodenum and posterior pointing towards the left part of the abdominal cavity. The pancreas releases digestive enzymes to complete the process of chemical digestion. • Liver • The liver is a roughly triangular, reddish-brown accessory organ of the digestive system located to the right of the stomach. It produces bile, which helps in the digestion of fat in the small intestine. The bile is stored and recycled in the gallbladder. It is a small, pear-shaped organ which is located just next to the liver.
  • 7. Digestion Process • The process of digestion begins from the mouth and ends in the small intestine – the large intestines’ main function is to absorb the remaining water from the undigested food and enable bacterial fermentation of materials that can no longer be digested. • The alimentary canal or the gastrointestinal tract is a series of hollow organs and tubes that begins from the mouth cavity and continues into the pharynx, through the stomach, small intestines, large intestines, and finally ending at the anus. Food particles gradually get digested as they travel through various compartments of the gastrointestinal tract. • The digestion process takes place in the following steps. • Ingestion • The very first step involves mastication (chewing). The salivary glands, along with the tongue, helps to moisten and lubricate food, before being pushed down into the food pipe. • Mixing and Movement • It involves the process of lubricating and manipulating food and pushing it down the food through the food pipe (using peristalsis), and into the stomach.
  • 8. • Secretion • The stomach, small intestine, liver, and pancreas secrete enzymes and acids to aid the process of digestion. It functions by breaking down food particles into simple components and easily absorbable components. • Digestion • The process of converting complex food particles into simpler substances in the presence of enzymes and acids secreted by different digestive organs. • Absorption • This process begins in the small intestine where most of the nutrients and minerals are absorbed. The excess water in the indigestible matter is absorbed by the large intestines. • Excretion • The process of removing indigestible substances and waste by-products from the body through the process of defecation. • In a nutshell, the digestion process consists of the six following steps: • Ingestion Mixing and Movement Secretion Digestion Absorption Excretion ⇒ ⇒ ⇒ ⇒ ⇒
  • 9. Gastrointestinal Tract Definition “Gastrointestinal tract is the part of an organ system in humans and other animals that take in food, digest it, absorb nutrients and expel it out in the form of feces.”
  • 12. Gastrointestinal Tract Anatomy • The gastrointestinal tract in humans begins at the mouth, continuing through the esophagus, stomach, and small and large intestines. The GI tract is about 9 meters in length. • There are many supporting organs, such as the liver, which helps by secreting enzymes that are necessary for the digestion of food. • The human GI tract can be divided into two halves, namely: • Upper GI tract • Lower GI tract
  • 13. Upper Gastrointestinal Tract • The upper GI consists of the following organs: • Mouth • It includes the teeth, tongue, and buccal mucous membranes containing the ends of the salivary glands that continue with the soft palate, floor of the mouth, and underside of the tongue. Mouth functions by chewing the food, constantly by the muscular action of the tongue, cheeks, and teeth through the lower jaw and upper jaw. • Pharynx • The pharynx is enclosed in the neck and functions as part of both the digestive system and the respiratory system. It protects the food from entering the trachea and lungs. • esophagus • A muscular tube-like structure that functions by carrying food to the stomach. Once the chewed food reaches the esophagus from the mouth, the action of swallowing becomes involuntary and is controlled by the esophagus. • Stomach • This is where most of the digestion takes place. The stomach is a J-shaped bag-like organ that stores the food temporarily, breaks it down, mixes and churns it with enzymes and other digestive fluids and finally, passes it along to the small intestine.
  • 14. Lower Gastrointestinal Tract • The lower GI consists of the following organs: • Small Intestine • The small intestine is a coiled thin tube, about 6 meters in length, where most of the absorption of nutrients takes place. Food is mixed with enzymes from the liver and the pancreas in the small intestine. The surfaces of the small intestine function by absorbing the nutrients from the food into the bloodstream, which carries them to the rest of the body. • Large Intestine • The large intestine, also known as the Colon, is a thick tubular organ wrapped around the small intestine. Its primary function is to process the waste products and absorb any remaining nutrients and water back into the system. The remaining waste is then sent to the rectum and discharged from the body as stool.
  • 15. Digestion: 1.Before the body can use the food, it has to be first absorbed by the bloodstream. 2.This is done by breaking the large, insoluble food molecules into smaller, soluble ones by the process of digestion, which is performed by the digestive system. 3.Digestion is a mechanical and chemical breakdown of food into small organic fragments. 4.Mechanical digestion referred to the physical breakdown of large pieces of food into smaller pieces that can subsequently be accessed by digestive enzymes. 5.In chemical digestion, these enzymes break down food into small molecules that the body can use. 6.Relevant organs are the mouth and teeth, alimentary canal, stomach, and duodenum.
  • 16. Absorption: 1.A simple product of digestion is small enough to be absorbed by the epithelial cells of the intestinal villi. 2.Each day the alimentary canal processes up to 10 liters of food, liquids, and GI secretions, also less than one liter enters the large intestine. 3.Almost all ingested food, 80% of electrolytes, and 90% of water are absorbed in the small intestine. 4.Although the entire small intestines are involved in the absorption of water and lipids, most absorption of carbohydrates and proteins occurs in the jejunum. 5.The small intestine is very highly efficient at this, absorbing monosaccharides at an estimated rate of 120 grams per hour. 6.Especially, bile salts and vitamin B12 are absorbed in the terminal ileum.
  • 17. Assimilation: 1.It is the movement of the digested food molecules into the cells of the body from where they are used. 2.The liver is important in assimilation 3.For example, glucose is used in respiration to provide energy, and also amino acids are used to build new proteins. 4.The fate of the absorbed food glucose for energy production, amino acids for building up body materials, and fats for energy reserve.
  • 18. Gastrointestinal hormones • Gastrin • Gastrin is produced by G cells of the antral glands of the duodenum and small intestine • Actions: ◦ Stimulation of gastric acid secretion ◦ motility and Trophic effects on parietal cell mass • secretion of hydrochloric acid (HCl) into the stomach. • pH > 3.0 • also known as the CCKB receptor
  • 19. Cholecystokinin (CCK) • Cholecystokinin (CCK) is produced by I cells of the duodenum and upper jejunum with 115 amino acid prepropeptide. • Specificity determined by a sulfated tyrosine • As most important function is considered to be the stimulation of the secretion of pancreatic juice, induction of the contractions of the gallbladder and relaxation of Oddi’s sphincter • Regulation ◦ Fat and protein digestive products, especially Phe and Trp • CCKA receptor is present in the gallbladder and pancreas. • CCKB (gastrin) receptor is expressed in the brain and gastric fundus Actions: ◦ Indirectly stimulates pancreatic exocrine secretion ◦ Stimulates gallbladder contraction ◦ Inhibits gastric emptying ◦ Trophic effects on the pancreas ◦ Influences sensation of satiety
  • 20. • Secretin • Structure: 27 amino acids • Secretin is produced by S cells of the duodenum and jejunum • It stimulates the secretion of fluid and bicarbonates in pancreas, large intestine, and secretion of pepsin in the stomach. • It inhibits the secretion of HCl, motility of the stomach and the tonus of the lower oesophageal sphincter. • Stimulation of pancreatic water and bicarbonate secretion • Secretin secretion is stimulated by – acidification of the duodenum – products of fat digestion
  • 21. Somatostatin • Somatostatin (SMS) – is produced by endocrine and paracrine D cells in the entire intestine • It inhibits the motility in GIT and exocrine and endocrine secretions. • Splanchnic vasoconstriction Clinical Applications • Secretory diarrhea • Pancreatic secretions • Gastrointestinal hemorrhage (variceal bleeding)
  • 22. Motilin • 22 amino acids • Motilin is produced in M cells of the duodenum. It induces the contractile activity of the stomach and intestines • Actions: serum levels parallel that of the interdigestive motor complex • Pharmacology: erythromycin binds to the motilin receptor and acts as an agonist • Used in the clinical setting to promote motility
  • 23. • Our digestive system provides us with one of the essential functions of life, Nutrition, which helps to provide us with energy and provides our body with building blocks to create new body cells from. • The digestive system is essentially a tube which extends from the mouth to the rectum. • Components of the digestive system • Food passes through the digestive system in the following order: • Mouth • Esophagus • Stomach • The small intestine • Colon (large intestine) • Rectum • Through this process a number of enzymes act on the food we eat (inc liver, pancreas, gall bladder). • The mouth and esophagus • In the mouth, saliva acts to start to break down carbohydrates thanks to an enzyme called amylase. The esophagus is a tube, controlled by muscles and autonomic nerves, that helps food to travel from the mouth to the stomach.
  • 24. • The stomach • The stomach coats the food with a mixture of acid and digestive enzymes to help break the food down further. A layer of mucous protects the stomach lining from being damaged by the acid. • The bottom of the stomach is able to contract, which helps to speed up the process. When the food is broken down sufficiently the stomach releases its contents into the duodenum.
  • 25. • The small intestine • The small intestine is categorised in three parts; the duodenum being the first, the jejunum second and the ileum the final part. • When food enters the duodenum, the pancreas releases enzymes to help break down fat, protein and carbohydrate The gall bladder releases bile, which has been produced by the liver, to help further break fats down into a form that can be absorbed by the intestines. • The small intestine is lined with finger-like projections, called villi, which provide a very large surface area facilitating the absorption of nutrients, including carbohydrates, proteins and fats, into the bloodstream. • The small intestine contains a number of receptive cells which detect the presence of macronutrients and secrete hormones which instructs the pancreas on how much insulin and glucagon to release.
  • 26. • The colon (large intestine) • The final stage of the digestive system is the colon (large intestine) which absorbs water and salts before the remains are passed out of the rectum as faeces. The colon can also help to absorb remaining carbohydrate and some fats.
  • 27. Liver • The liver is located in the upper right portion of the abdomen. It is the largest gland in the human body that performs several important functions. It is the only organ that has the ability to regenerate efficiently. Liver Anatomy Structure of Liver : • The liver is a triangular, bilobed structure consisting of a larger right lobe and a smaller left lobe. The falciform ligament separates the two lobes. • A layer of fibrous tissue called Glisson’s capsule covers the liver. This capsule is covered by the peritoneum. This protects the liver from physical damage. • It has two main sources of blood: • Hepatic Portal Vein carries nutrient-rich blood from the digestive system. • Hepatic Artery carries oxygenated blood from the heart.
  • 28. • Functions of Liver • The important functions of the liver are mentioned below: • Production of Bile • Bile, which helps in the digestion and absorption of fats, vitamins and cholesterol is produced in the liver. • Absorption of Bilirubin • Bilirubin is formed by the breakdown of haemoglobin. The iron released is stored in the liver to make next-generation blood cells. • Supporting Blood Clots • Bile is responsible for the absorption of vitamin K. If bile is not produced, clotting factors will not be produced. • Metabolization of Fats • Bile helps in the breakdown and digestion of fats. • Carbohydrate Metabolization • The carbohydrates stored in the liver as glycogen are broken down into glucose and released into the blood to maintain glucose levels. • Storage of Vitamins and Minerals • Vitamins A, D, E, K, and B12 are stored in the liver. It also stores iron in the form of ferritin to form new red blood cells. • Metabolization of Proteins • Bile helps in the digestion of proteins. • Filtering Blood • The compounds such as hormones, alcohol, etc are filtered by the liver from the blood. • Immunological Function • The liver contains Kuffer cells involved in immune activity. These destroy any disease-causing agents. • Albumin Production • Albumin transports fatty acids and steroids to maintain correct pressure and prevent leakage of blood vessels. • Angiotensinogen Synthesis • This hormone is responsible for the narrowing of blood vessels which results in an increase in blood pressure. • Regeneration of Liver • The liver has the ability to regrow in all vertebrates. The functions of the liver are not lost during the growth process. In humans, regeneration takes 8-15 days. • In mice, the same process takes around 5-7 days.
  • 29. Spleen • The spleen is a large, encapsulated, bean-shaped organ that is situated on the left side of the body below the diaphragm. The spleen contains T and B lymphocytes as well as many phagocytes and is a major component of the mononuclear phagocyte system. Although the structure resembles that of the large lymph nodes, the spleen differs from a lymph node in having no lymphatic drainage, and also in containing large numbers of red cells.
  • 30. Structure of spleen • It is a dark purple-coloured organ, which lies in the left hypochondriae region of the abdomen, between the fundus of the stomach and the diaphragm. • It varies in size and weight during the lifetime of an individual but in an adult is usually about 12 cm long, 8cm broad and 3-4 cm thick weighing about 200gm. • The spleen has diaphragmatic and visceral surfaces. The diaphragmatic surface is in contact with the inner surface of the diaphragm. • The spleen has an outer coat of peritoneum which is firmly adherent to the internal fibro-elastic coat or splenic capsule that dips into the organ, forming trabeculae.
  • 31. Function of Spleen 1.The main immunological function of the spleen is to filter the blood by trapping bloodborne microbes and producing an immune response to them. It is particularly important for B cell responses to polysaccharide antigens. 2.The spleen is formed partly by lymphatic tissue which produces T lymphocytes and B lymphocytes. 3.Due to the presence of lymphoid reticulo-endothelial tissue, the spleen is involved in producing antibodies and antitoxin. 4.In the foetus, the spleen acts as an important haemopoitic organ. 5.It also removes damaged red blood cells and immune complexes. 6.It can act as an erythropoietic organ which acts as a reservoir of erythrocytes or a reservoir for blood. 7.Those individuals who have had their spleens removed (splenectomized) have a greater susceptibility to infection with encapsulated bacteria, and are at increased risk of severe malarial infections, which indicates its major importance in immunity.
  • 32. Gallbladder • The gallbladder is a pear-shaped, hollow structure located under the liver and on the right side of the abdomen. Its primary function is to store and concentrate bile, a yellow-brown digestive enzyme produced by the liver. The gallbladder is part of the biliary tract. • The gallbladder serves as a reservoir for bile while it’s not being used for digestion. The gallbladder’s absorbent lining concentrates the stored bile. When food enters the small intestine, a hormone called cholecystokinin is released, signaling the gallbladder to contract and secrete bile into the small intestine through the common bile duct. • The bile helps the digestive process by breaking up fats. It also drains waste products from the liver into the duodenum, a part of the small intestine.
  • 33. Structure of the Gallbladder • The approximate shape and size of the gallbladder are described as pear- like. Its average storage capacity is between 30 to 50 milliliters (mL). The gallbladder structure is generally divided into three parts: the fundus, the body, and the neck.
  • 34. Gallbladder Function • To store and concentrate bile. • To respond to intestinal hormones (such as cholecystokinin) to empty and refill its bile stores. • To contribute to regulating the composition of bile (the percentage of water, bile salts and more) • To control the flow of bile into the small intestine.
  • 35. What is Pancreas? • Pancreas is an abdominal organ located behind the stomach and surrounded by spleen, liver and small intestine. It is a vital part of the digestive system and is responsible for regulating blood sugar levels. • The pancreas secretes digestive enzymes such as amylase, proteases and lipase into the duodenum. These enzymes help in digesting sugar, proteins and fat respectively. Islets of Langerhans are embedded in the pancreas that secretes hormones such as insulin and glucagon into the blood.
  • 36. Pancreas Location • The pancreas is located in the abdomen. A part of it is placed between the stomach and the spine. The other part finds its place in the curve of the first section of the small intestine, known as the duodenum. • The head of the pancreas is on the right side of the abdomen and is connected to the duodenum through the pancreatic duct. The tail of the pancreas extends to the left side of the body.
  • 37. Pancreas Function • The pancreas performs the following functions: • Exocrine Function • The pancreas consists of exocrine glands that produce enzymes trypsin and chymotrypsin that are essential for digestion. These enzymes contain chymotrypsin and trypsin to digest proteins, amylase for the digestion of carbohydrates and lipase to break down fats. These pancreatic juices are liberated into the system of ducts and culminated in the pancreatic duct when the food enters the stomach. • Endocrine Function • The endocrine part of the pancreas comprises Islets of Langerhans that release insulin and glucagon directly into the bloodstream. They help in regulating the blood sugar levels of the body.
  • 38. Structure of Pancreas • Appearing as a pinkish-tan structure, the pancreas is a J-shaped organ and distinctly appears lobulated. The connective tissue involved renders septation to give rise to macroscopic lobules that make up the functional units of the exocrine pancreas. • In adult males, this wet structure approximately weighs 100 g, in adult females 85 g while in newborns it weighs about 5 g. The length of the adult gland is about 14 to 18 cm, width is 2 to 9 cm with a thickness of 2 to 3 cm. The structure can be distinguished into 4 main areas – head with the uncinate process, neck, body with tuber omentale and the tail. • Different parts of the Pancreas • The pancreas’ head is seen in the loop of the duodenum as it leaves the stomach • The body of the pancreas is seen posterior to the distal part of the stomach between the neck and the tail • The part of the pancreas seen anterior to the aorta is kind of thin compared to the nearby parts of the head and the body of the pancreas. This area is at times assigned as the neck and indicates the junction of the body and head • The common bile duct passes through the pancreas’ head and joins the main pancreatic duct, seen near the duodenum. The part which lies closest to the liver in a groove on the dorsal part of the head
  • 39. Jaundice • Adults and children with jaundice may notice a yellowish tinge to their skin, mucous membranes, and the whites of the eyes. It can happen with various health conditions and usually indicates a problem with the liver or bile ducts.
  • 40. Causes and risk factors • According to the American Family Physician (AAFP), jaundice is the yellowing of the skin, mucous membranes, and the whites of the eyes that occurs when the body does not process bilirubin as it should. • Bilirubin levels increase as the red blood cells naturally break down. Typically, the liver filters this waste material out of the bloodstream and turns it into a new form called conjugated bilirubin. The new form then exits the body in a person’s stool. • If there is too much bilirubin for the liver to process, it can build up in the body. This is known as hyperbilirubinemia, and it causes the yellow color in the skin and eyes. • Jaundice typically occurs due to an underlying disorder that either causes the production of too much bilirubin or prevents the liver from eliminating it. • Some possible underlying conditions and causes of jaundice include: • side effects of certain medications • gallstone disease • excessive alcohol consumption • gallbladder or pancreatic cancer • cirrhosis, which is a disease that causes scar tissue to replace healthy tissue in the liver • hepatitis or other liver infections • hemolytic anemia
  • 41. Cirrhosis • Cirrhosis of the liver is permanent scarring that damages your liver and interferes with its functioning. It can lead to liver failure. Cirrhosis is the result of persistent liver damage over many years. Alcohol and drugs, viruses and metabolic factors are the most common causes. • Cirrhosis of the liver is late stage liver disease, in which healthy liver tissue has been gradually replaced with scar tissue. This is a result of long-term, chronic hepatitis. Hepatitis is inflammation in your liver, which has many causes. When inflammation is ongoing, your liver attempts to repair itself by scarring. But too much scar tissue prevents your liver from working properly. The end stage is chronic liver failure.
  • 42. What are the first signs of cirrhosis of the liver? Early signs and symptoms of cirrhosis may include: •Nausea or loss of appetite. •Feeling weak or tired (fatigue). •Feeling generally ill (malaise). •Upper abdominal pain (especially on the right). •Visible blood vessels that look like spiders (spider angiomas). •Redness on the palms of your hands (palmar erythema).
  • 43. What are symptoms of advancing cirrhosis? • Recognizable symptoms of cirrhosis fall into two categories: symptoms related to declining liver function, and symptoms related to portal hypertension. Symptoms of stalled bile flow, like jaundice, are common indicators of declining liver function. Symptoms of portal hypertension indicate cirrhosis specifically. It’s scar tissue in your liver that compresses your portal vein. • Cirrhosis symptoms related to declining liver function include: • Jaundice (yellow tint to your skin and eyes). • Pruritus (itchy skin, but with no visible rash). • Dark-colored pee and light-colored poop. • Digestive difficulties, especially with fats. • Small yellow bumps of fat deposits on your skin or eyelids. • Unexplained weight loss and muscle loss. • Hepatic encephalopathy (confusion, disorientation, mood changes). • Motor dysfunction (twitching, tremors or lapses in muscle control). • Disruptions to your menstrual cycle. • Enlarged male breast tissue and shrunken testes in people AMAB. • Cirrhosis symptoms related to portal hypertension include: • Swelling in your abdomen (ascites). • Swelling in your hands, feet, legs and/or face (edema). • Easy bleeding and bruising (coagulopathy)
  • 44. What causes cirrhosis of the liver? • Cirrhosis is a gradual scarring process that’s triggered by chronic inflammation in your liver. Any chronic liver disease that causes chronic hepatitis can lead to cirrhosis. The most common causes include: • Alcohol-induced hepatitis. This is chronic liver damage from chronic heavy alcohol use. Alcohol may be the most well-known cause of liver cirrhosis, but nonalcoholic causes are also common. • Non-alcohol-related steatohepatitis. This is chronic damage from excess fat storage in your liver. It’s related to metabolic factors like high blood lipids, blood sugar and blood pressure. • Chronic hepatitis C infection. Hepatitis C is a viral infection that becomes chronic in most people. It’s now curable with antivirals, but many people don’t realize they have it. • Chronic hepatitis B infection. Hepatitis B is a viral infection that may become chronic in a minority of people. If it does, you’ll have it for life. It’s treatable, but not curable.
  • 45. Pancreatitis • Pancreatitis is inflammation of the pancreas. Inflammation is immune system activity that can cause swelling, pain, and changes in how an organ or tissues work. • The pancreas is a long, flat gland that's tucked behind the stomach. The pancreas helps the body digest food and regulates blood sugars. • Pancreatitis can be an acute condition. This means it appears suddenly and generally lasts a short time. Chronic pancreatitis is a long-term condition. The damage to the pancreas can get worse over time. • Acute pancreatitis may improve on its own. More-serious disease requires treatment in a hospital and can cause life-threatening complications.
  • 46. Symptoms • Symptoms of pancreatitis may vary. Acute pancreatitis symptoms may include: • Pain in the upper belly. • Pain in the upper belly that radiates to the back. • Tenderness when touching the belly. • Fever. • Rapid pulse. • Upset stomach. • Vomiting.
  • 47. Causes • The pancreas has two major roles. It produces insulin, which helps the body manage and use sugars. • The pancreas also produces dietary juices, called enzymes, that help with digestion. The pancreas makes and stores "turned off" versions of the enzymes. After the pancreas sends the enzymes into the small intestine, they are "turned on" and break down proteins in the small intestine. • If the enzymes are turned on too soon, they can start acting like digestive juices inside the pancreas. The action can irritate, damage or destroy cells. This problem, in turn, leads to immune system responses that cause swelling and other events that affect how the pancreas works. • Several conditions can lead to acute pancreatitis, including: • Blockage in the bile duct caused by gallstones. • Heavy alcohol use. • Certain medicines. • High triglyceride levels in the blood. • High calcium levels in the blood. • Pancreas cancer. • Injuries from trauma or surgery.