Lecture 11

Question 1

What is a electrogenic pump?

Answer 1

Pumps protons into the extracellular fluid using atp against gradient, must use atp or H+ will diffuse back into the cell

Question 2

What is bulk transport and what are the two types of it

Answer 2

• bulk transport is large molecules such as proteins and polysaccharides cross the membrane in bulk via vesicles (needs atp)
• 2 types: 1. Exocytosis is release from the cell
  2. Endocytosis is uptake

Question 3

What are the sites of enzyme activity?

Answer 3

• cytosol

- membranes : plasma, endo, mitochondrial, thylakoid

Question 4

How are enzymes formed

Answer 4

They are inherited from a common anstor similarities in structure and function

Question 5

What can change an enzymes structure

Answer 5

Artificial selection which can cause mutations in he DNA or amino acid changes in the enzyme

Question 6

What is enzyme activity?

Answer 6

Total amount of reactant over concerted to product over time

Question 7

What does the activity of each enzyme molecule depend on

Answer 7

• PH, temperature etc
• concentrations of substrates and products
• inhibitors and activators

Question 8

What is a coenzyme?

Answer 8

Organic cofactor eg vitimins

Question 9

How can a substrate activate an enzyme?

Answer 9

By stabilizing it

Question 10

What are the 2 ways something can progeny enzyme activity

Answer 10

1. Bins to active sight and prevent substrate binding-competitive inhibition
2. Bins to another sight-change in enzyme shape that prevents substrate binding- non competitive inhibition

Question 11

What is a proton pump?

Answer 11

Pumps hydrogen ions out of the cell against gradient using atp

Question 12

What is a sucrose hydrogen transport?

Answer 12

Allows hydrogen back into the cell which releases energy and that energy is used to move sucrose against the gradient

Question 13

What is catabolism and anabolism

Answer 13

Catabolism releases energy and breaks up a large molecule into smaller molecules which are used for anabolism which is the opposite of catabolism