1. Which molecule is a sugar?
2. Why is sweat a good coolant for the body?
A. The arterioles that transfer water to sweat move closer to the skin surface when it is hot.
B. Breaking H bonds between water molecules in sweat requires energy from body heat.
C. Sweat contains minerals such as sodium chloride.
D. Sweat is non-polar.
3. Which is an effect of protein denaturation?
A. The order of amino acids is changed when the protein overheats.
B. The bonds between amino acids are broken by condensation.
C. Parts of the protein become linked together by hydrolysis.
D. The three-dimensional structure of the protein is altered.
4. What usually distinguishes DNA from RNA?
5. Research has shown that the genetic code is not entirely universal. Which research finding has shown this?
A. Some amino acids are coded for by more than one codon.
B. There are differences between the base sequences of genes in different species.
C. In some organisms the genetic code for mitochondria differs from the genetic code for the nucleus.
D. Some codons code for the addition of an amino acid and some code for the termination of translation.
6. This is a sequence of nucleotides from a section of mRNA.
From which DNA sequence has it been transcribed?
7. Which gas produces most of the bubbles in bread dough?
C. Carbon dioxide
D. Water vapour
8. What is the process shown in this image?
A. Binary fission of a prokaryotic cell
B. Telophase II in a eukaryotic cell
C. End of mitosis in a prokaryotic cell
D. Cytokinesis of a eukaryotic cell
9. What distinguishes prokaryotic cells and eukaryotic cells?
10. What can be deduced about a striated muscle fi bre from both of these statements?
“A eukaryotic cell has one nucleus.”
“A striated muscle fi bre has many nuclei.”
A. It is prokaryotic.
B. It is an exception to cell theory.
C. It consists of aseptate hyphae.
D. It is preparing to divide.