AQA Combined Science Unit 2: Organisation 1
The diagram below shows the lock and key model of
enzyme function. Label the diagram using the following
words:
enzyme, active site, substrate, products, enzyme-
substrate complex.
Place the following structures in order from smallest to
largest:
1.
2.
3.
4.
5.
Define what an enzyme is.
What is the function of phloem tissue?
Transpiration is:
(Tick the correct box.)
The movement of water molecules from a
high water concentration to a lower water
concentration across a partially permeable
membrane.
The evaporation and diffusion of water from the
leaves of a plant.
The movement of glucose molecules around the
plant.
Name three factors that affect the rate of
transpiration.
•
•
•
•
The xylem tissue is composed of hollow tubes
strengthened by lignin. What is the function of xylem
tissue?
Describe how a root hair cell is adapted for the efficient
uptake of water and mineral ions.
Where, in the plant, is meristem tissue located?
Describe how to test for starch.
1.
2.
3.
Describe how to test for protein.
1.
2.
3.
Enzymes are described as being specific to a substrate.
What does this mean? Use the diagram to help your
explanation.
Bile is made in the liver and stored in the gall bladder.
Bile neutralises s a to lower
the pH so protease enzymes can work.
It also e fats to give them a larger
s a for lipase to work
on. This speeds up d .
Describe how to carry out the test for reducing sugars.
Keywords: Benedict’s, heat, colour change, blue, red.
1.
2.
3.
4.
The is the part of the body
where food is absorbed into the bloodstream.
a d hl
i
j
k
m
n
e
f
g
b
c
cell organ
tissue
nucleus
organism
