Transport in Blood Answers

Transport in Blood Answers

• 1.
  Transport of Substancesin Blood Blood transports a variety of substances. The mode of transport of a substance depends on its solubility in water. Research the following substances and complete the table below. Substance Mode of transport in blood Explanation Glucose Dissolved in plasma Because it is polar, glucose is highly soluble Amino acids Usually dissolved in plasma, but depends on the amino acid. Not all amino acids are Not all amino acids are polar, so all will dissolve. Some require carrier proteins Cholesterol Transported in lipoproteins Cholesterol and fats are non-polar which makes them insoluble in water. Lipoproteins are small molecules made of phospholipids and proteins that coat the cholesterol/fat molecule, allowing it to travel in the plasma Fats Transported in lipoproteins Cholesterol and fats are non-polar which makes them insoluble in water. Lipoproteins are small molecules made of phospholipids and proteins that coat the cholesterol/fat molecule, allowing it to travel in the plasma Oxygen haemoglobin Oxygen doesn’t dissolve well in plasma (non-polar) so it binds to haemoglobin Sodium chloride Dissolved in plasma NaCl is soluble in water. Travels as ions
• 2.
  Comparing the ThermalProperties of Methane and Water Methane and water are both small molecules that have a similar molecular mass. Despite this, they have very different thermal properties. This is a result of hydrogen bonds forming between water molecules. Because methane is not polar, hydrogen bonds do not form. As a result, methane has much weaker intermolecular forces (the forces that hold molecules together) than water. Describe and compare their molecular structures. What is similar, and what is different? • Both covalent bonds • • Both contain hydrogen • • Both are small molecules • Methane is surrounded by hydrogen, meaning it is not polar • Water has a bent structure, causing it to be polar
• 3.
  1. Complete thetable on the next page to compare the thermal properties of methane and water. Property Definition Methane Water Explanation Melting Point The temperature at which a solid turns into a liquid -182 degrees C 0 degrees C Hydrogen bonding means more energy is required to separate water molecules and water is capable of absorbing more energy before changing state Specific heat capacity Water is able to absorb or give off a great deal of heat without changing temperature greatly. 2.2 J per g per degree C 4.2 per g per degree C Latent heat of vaporisation Water absorbs a great deal of heat when it evaporates, it is used as a cooling mechanisms in many organisms including ourselves in the form of sweat. 760 J/g 2257 J/g Boiling point The temperature at which a liquid turns into a gas -160 degrees C 100 degrees C