Notes

Question 1

what do the enzymes endopeptidases form?

Answer 1

Smaller peptides

Question 2

What is the role of bile in digestion

Answer 2

• Emulsifies fats
• Neutralises stomach acid
• Form micelles

Question 3

What are micelles and how are they involved in the absorption of products of digestion. Give one example

Answer 3

• Bile salts surrounded by fatty acids monoglycerides forming micelles
• These move into the epithelial cells through the cell membrane
• Once inside the cell, the micelles breakdown and the triglycerides reform

Question 4

explain how amino acids are absorbed by co-transport

Answer 4

• Sodium ions are actively transported into the blood from the epithelial cells by the sodium/potassium pump
• This lowers the sodium ion concentration in the cells
• Sodium ions and amino acids move together through co-transporter proteins from the lumen into the cells by co-transport
• Amino acids then move by facilitated diffusion into the blood from the epithelial cells

Question 5

WHAT IS FOI