biology paper 1- 2024
Study online at https://quizlet.com/_fke4gq
1. The ratio of saturated to unsaturated 1. More unsaturated fatty acids increases fluidity (in
fatty acids in a cell-surface membrane (cell-surface membrane);
determines the extent of the mem- 2. (Making cell-surface) membrane more fluid/
brane's fluidity. flexible;
Suggest and explain why there was 3. Easy to engulf;
more phagocytosis. [3 marks]
2. Describe the processes of facilitated 2. (Facilitated diffusion) movement down a
diffusion and active transport. concentration gradient via carrier/channel
[3 marks] protein;
3. (Active transport) movement against a
concentration gradient via carrier protein using
ATP;
3. What are microvilli? (Highly) folded cell(-surface) membrane;
[1 mark]
4. Vitamin A is a fat-soluble substance. 1. Combine/mix/join with bile salts;
Micelles are involved in the process of 2. Make (more) soluble (in water);
vitamin A absorption. 3. Diffuses (into cells/ileum);
Describe the process of vitamin A ab-
sorption into cells lining the ileum.
[3 marks]
5. Describe how we breathe in. 1. Diaphragm (muscle) contracts pulling di-
[3 marks] aphragm
down;
2. External intercostal muscles contract
pulling/moving ribs upwards/outwards;
3. (Causes) volume increase and pressure
decrease in thoracic cavity;
6.
1/5
, biology paper 1- 2024
Study online at https://quizlet.com/_fke4gq
Use your understanding of osmosis to 1. Molasses/solution has a lower water potential
explain why the air pressure in the 2. Water moves in (across) partially/selectively per-
tube increased. meable bladder;
[3 marks] 3. Increased (molasses/solution) volume
7. Describe the appearance and be- (In prophase)
haviour of chromosomes during 1. Chromosomes/chromatids (continue to) con-
prophase and during anaphase of mi- dense;
tosis. 2. Chromosomes attach to spindle (fibres)
[4 marks] (In anaphase)
3. Centromeres divide/split;
4. Chromosomes/chromatids moved/pulled to
opposite poles/sides/ends;
8. r = -0.98 (P < 0.05) 1. Strong/significant negative (correlation);
What can you conclude from this re- 2. (Because probability of) correlation occurring
sult? by
[2 marks] chance is less than / < 0.%
3. Reject null hypothesis;
9. Give three structural differences be- mRNA
tween an mRNA molecule and a tRNA 1. (Has) codon(s)
molecule. 2. No hydrogen/H
[3 marks] bonds
3. Linear/straight/not
folded
4. Long/many
nucleotides/bases
tRNA
1. (Has) anticodon;
2. Has hydrogen/H
bonds
2/5
Study online at https://quizlet.com/_fke4gq
1. The ratio of saturated to unsaturated 1. More unsaturated fatty acids increases fluidity (in
fatty acids in a cell-surface membrane (cell-surface membrane);
determines the extent of the mem- 2. (Making cell-surface) membrane more fluid/
brane's fluidity. flexible;
Suggest and explain why there was 3. Easy to engulf;
more phagocytosis. [3 marks]
2. Describe the processes of facilitated 2. (Facilitated diffusion) movement down a
diffusion and active transport. concentration gradient via carrier/channel
[3 marks] protein;
3. (Active transport) movement against a
concentration gradient via carrier protein using
ATP;
3. What are microvilli? (Highly) folded cell(-surface) membrane;
[1 mark]
4. Vitamin A is a fat-soluble substance. 1. Combine/mix/join with bile salts;
Micelles are involved in the process of 2. Make (more) soluble (in water);
vitamin A absorption. 3. Diffuses (into cells/ileum);
Describe the process of vitamin A ab-
sorption into cells lining the ileum.
[3 marks]
5. Describe how we breathe in. 1. Diaphragm (muscle) contracts pulling di-
[3 marks] aphragm
down;
2. External intercostal muscles contract
pulling/moving ribs upwards/outwards;
3. (Causes) volume increase and pressure
decrease in thoracic cavity;
6.
1/5
, biology paper 1- 2024
Study online at https://quizlet.com/_fke4gq
Use your understanding of osmosis to 1. Molasses/solution has a lower water potential
explain why the air pressure in the 2. Water moves in (across) partially/selectively per-
tube increased. meable bladder;
[3 marks] 3. Increased (molasses/solution) volume
7. Describe the appearance and be- (In prophase)
haviour of chromosomes during 1. Chromosomes/chromatids (continue to) con-
prophase and during anaphase of mi- dense;
tosis. 2. Chromosomes attach to spindle (fibres)
[4 marks] (In anaphase)
3. Centromeres divide/split;
4. Chromosomes/chromatids moved/pulled to
opposite poles/sides/ends;
8. r = -0.98 (P < 0.05) 1. Strong/significant negative (correlation);
What can you conclude from this re- 2. (Because probability of) correlation occurring
sult? by
[2 marks] chance is less than / < 0.%
3. Reject null hypothesis;
9. Give three structural differences be- mRNA
tween an mRNA molecule and a tRNA 1. (Has) codon(s)
molecule. 2. No hydrogen/H
[3 marks] bonds
3. Linear/straight/not
folded
4. Long/many
nucleotides/bases
tRNA
1. (Has) anticodon;
2. Has hydrogen/H
bonds
2/5
