21 Breadth

Question 1

What describes the role of CITES

Answer 1

Restricting the trade in individuals of endangered species

Question 2

What results in the formation of tissue fluid

Answer 2

Oncotic Pressure < Hydrostatic Pressure

Question 3

Explain why the rate of reaction changes after optimum ph 8

Answer 3

The enzyme denatures after ph 8 as there is a change in active site so fewer enzyme substrate complex formed

Question 4

Explain a practical to collect the volume of gas using a measuring cylinder

Answer 4

Ensure the measuring cylinder is full of water, measure the starting volume
add liver to hydrogen peroxide solution and start stopwatch
read the volume of water displaced every 30 seconds

Question 5

Temperature and enzyme concentration are two factors that affect the activity of enzymes
Describe how variations in these two factors affect enzyme activity

Answer 5

As temperature increases from 0 to optimum the enzyme activity increases, this is because there is an increase in kinetic energy so there are more successful collisions.
As temperature increases above optimum temperature enzyme activity decreases this is due to the shape of the active site denaturing and the substrate is no longer complementary meaning it cannot form enzyme substrate complexes.

As concentration of enzyme increases enzyme activity increases. The enzyme activity decreases when substrate becomes limiting.

Question 6

What stages of meiosis does crossing over occur and independent assortment

Answer 6

Crossing over - prophase 1
Independent assortment - metaphase 1 and 2