Cambridge IGCSE™
* 2 9 5 7 4 9 7 8 0 3 *
BIOLOGY 0610/42
Paper 4 Theory (Extended) October/November 2024
1 hour 15 minutes
You must answer on the question paper.
No additional materials are needed.
INSTRUCTIONS
● Answer all questions.
● Use a black or dark blue pen. You may use an HB pencil for any diagrams or graphs.
● Write your name, centre number and candidate number in the boxes at the top of the page.
● Write your answer to each question in the space provided.
● Do not use an erasable pen or correction fluid.
● Do not write on any bar codes.
● You may use a calculator.
● You should show all your working and use appropriate units.
INFORMATION
● The total mark for this paper is 80.
● The number of marks for each question or part question is shown in brackets [ ].
This document has 16 pages. Any blank pages are indicated.
DC (PB/CB) 336155/3
© UCLES 2024 [Turn over
, * 0000800000002 *
DO NOT WRITE IN THIS MARGIN
2
1 (a) Organisms from the genus Chlorella are protoctists.
State the additional information required to name Chlorella according to the binomial system.
............................................................................................................................................. [1]
(b) Fig. 1.1 shows the structure of an organism from the genus Chlorella.
cytoplasm
DO NOT WRITE IN THIS MARGIN
nucleus cell wall
cell membrane
Cell wall composition: chloroplast
Cellulose> plants
Chitin> fungi
Murine >Bacteria or
DO NOT WRITE IN THIS MARGIN
prokaryotes
Fig. 1.1
(i) Identify two cell structures in Fig. 1.1 that indicate that Chlorella is not a prokaryote.
1 .........................................................................................................................................
2 .........................................................................................................................................
[2]
(ii) Identify two cell structures in Fig. 1.1 that are found in both fungi and protoctists.
DO NOT WRITE IN THIS MARGIN
1 .........................................................................................................................................
2 .........................................................................................................................................
[2]
(iii) State the names of two other kingdoms, apart from fungus, prokaryote and protoctist.
Viru's and non living cells has no cytoplasm
Kingdoms: ............................................................ and ............................................................ [1]
Animals: multicellular, membrane bound organelles (mitochondria,ER,vesicles,nucleus) ribosomes are not organelles.
Plants; multicellular, membrane bound organelles same as animals but instead of vesicles vacuoles and chloroplast is
present.cell wall contains cellulose
DO NOT WRITE IN THIS MARGIN
Fungi; mainly multicellular (yeast unicellular), has chitin in cell wall and a large vacuole & bound organelles like
mitochondria and nucleus
protoctist: can have feature of either plants or animals but unicellular (can either have chloroplast and be autotrophic
making food by photosynthesis or be heterotrophic-
bacteria prokaryote that have looped dna, smaller ribosomes , flagellum, cell wall made of murein
© UCLES 2024 0610/42/O/N/24
, * 0000800000003 *
DO NOT WRITE IN THIS MARGIN
Type y
3
(c) Chlorella is sold as a nutritional supplement.
Spirulina is another nutritional supplement.
Table 1.1 shows some nutritional information for Chlorella and Spirulina supplements and the
recommended daily intake for some nutrients.
Table 1.1
mass of nutrient
/ mg per 100 g of supplement average recommended
DO NOT WRITE IN THIS MARGIN
nutrient daily intake in adults
Chlorella Spirulina / mg per day
supplement supplement
vitamin C 0.74 0.00 80.00
calcium 120.00 5.10 1000.00
iron 37.00 75.50 12.00
(i) One tablet contains 5 g of Chlorella supplement.
Using the information in Table 1.1, calculate the number of tablets of Chlorella supplement
a person needs to take to provide the recommended daily intake of iron.
DO NOT WRITE IN THIS MARGIN
Give your answer to one decimal place.
Space for working.
.............................................. tablets [3]
DO NOT WRITE IN THIS MARGIN
(ii) Explain the advantages of taking Chlorella as a dietary supplement rather than Spirulina.
Use the data in Table 1.1 to justify your answer.
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
DO NOT WRITE IN THIS MARGIN
...........................................................................................................................................
...........................................................................................................................................
...........................................................................................................................................
..................................................................................................................................... [4]
© UCLES 2024 0610/42/O/N/24 [Turn over