1. Which labelled structure on the electron micrograph below identifies this as a plant cell and not an animal cell?
2. What is the sequence of stages during the cell cycle?
A. G1 → S → G2 → mitosis → cytokinesis
B. mitosis → G1 → G2 → cytokinesis → S
C. G1 → G2 → S → mitosis → cytokinesis
D. G1 → G2 → mitosis → cytokinesis → S
3. The graph below shows the correlation between the biomass of a marine worm, Arenicola, and the percentage of organic nitrogen in the sand where it lives.
What statement can be made from the data?
A. The increase in the biomass of the worm is due to an increase in the percentage of organic nitrogen.
B. There is no relationship between the biomass of the worm and the percentage of organic nitrogen.
C. The increase in the percentage of organic nitrogen is due to an increase in the biomass of the worm.
D. As the biomass of the worm increases so does the percentage of organic nitrogen.
4. What is the difference between the structure of all prokaryotes and all eukaryotes?
5. What does facilitated diffusion across a cell membrane require?
6. The graph below represents the amount of DNA during the cell cycle. Which part of the graph represents metaphase?
7. Which diagram best illustrates the interactions between water molecules?
8. What chemical reaction is taking place when a dipeptide becomes two amino acids?
9. The base ratios in the DNA and RNA for an onion (Allium cepa) are given below.
What is the reason for the difference between these figures?
A. DNA is only found in the nucleus but RNA is found throughout the cell.
B. DNA is made entirely of double helix but RNA is not.
C. In DNA bases A and T are complementary but in RNA bases A and C are complementary.
D. RNA comes in three forms but DNA only comes in one form.
10. Which of the following will cause an enzyme to permanently lose its properties?
- I. Hydrolysis
- II. Freezing to –20 °C
- III. Dissolving it in water
A. I only
B. II only
C. I and II only
D. I and III only