2.3.4 - Changes in Blood Composition (around the body)

Question 1

Changes in blood compsition in the lungs

Answer 1

• Pulmonary artery: high carbon dioxide and low oxygen - deoxygenated blood
• Pulmonary vein: high oxygen and low carbon dioxide - oxygenated blood

Question 2

Small intestine (absorption, not digestion)

Answer 2

• Mesenteric arteries (artery taking oxygenated blood to small intestines) before the meal: low in glucose and amino acids.
• Hepatic Portal Vein (from the intestine to the liver): as the meal is being absorbed, the vein has high amino acids and glucose

Question 3

Liver

Answer 3

Liver has over 500 functions, but namely controls blood sugar levels and emulsification (breaking down fats, to increase surface area so enzymes can act upon it)

Blood having high glucose level: Insulin released from the pancreas causing the liver to absorb glucose. Glucose is converted into glycogen for energy storage.

Low blood glucose level: Glucagon is released from pancreas, causing the liver to convert glycogen to glucose and released in the blood stream

The liver also deaminates amino acids into
urea to be removed from the body

Question 4

Kidney

Answer 4

Excretes the nitrogenous waste and helps with osmoregulation (maintaining the salt and water levels, by hormones)

• Renal artery: delivers urea to the kidney, where nephrons filter urea from blood in the renal vein to remove urea from blood
• Renal vein: leaving the kidney is low in urea (purified)

Question 5

gly what now

Answer 5

glycogen (liver) is converted into glucose by glucagon (pancreas)
to be deposited into the blood stream when it has a low glucose level