iGCSE Biology (0610) 1.3 Features of organisms iGCSE Style Questions Paper 4

Question

(a) Organisms from the genus Chlorella are protoctists.

State the additional information required to name Chlorella according to the binomial system.

(b) Fig. 1.1 shows the structure of an organism from the genus Chlorella.

(i) Identify two cell structures in Fig. 1.1 that indicate that Chlorella is not a prokaryote.

(ii) Identify two cell structures in Fig. 1.1 that are found in both fungi and protoctists.

(iii) State the names of two other kingdoms, apart from fungus, prokaryote and protoctist ……………. and ……………. .

(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.

(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.
Give your answer to one decimal place.

(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.

(iii) State the name of one food that is a principal dietary source of vitamin C.

(d) Chlorella is also a good source of protein.

(i) State the importance of proteins in active transport.
(ii) State the name of the smaller molecules that proteins are made from.

▶️ Answer/Explanation

Solution

(a) Ans: species (name)

The binomial system requires both the genus and species name. Since “Chlorella” is the genus, the species name is needed for full classification.

(b)(i) Ans: nucleus ; chloroplast

Prokaryotes lack membrane-bound organelles. The presence of a nucleus and chloroplasts confirms Chlorella is a eukaryote.

(b)(ii) Ans: any two from: cytoplasm ; cell wall ; cell membrane ; nucleus

These structures are common in both fungi and protoctists, as they are eukaryotic organisms with similar cellular organization.

(b)(iii) Ans: animal and plant

The five-kingdom classification system includes Animalia and Plantae, alongside Fungi, Prokaryotae, and Protoctista.

(c)(i) Ans: 6.5 (tablets)

From Table 1.1, Chlorella has 15.4 mg iron per 100 g. For 5 g (one tablet), iron content is \( \frac{15.4 \times 5}{100} = 0.77 \, \text{mg} \). The recommended daily intake is 5 mg, so tablets needed = \( \frac{5}{0.77} \approx 6.5 \).

(c)(ii) Ans: Chlorella contains vitamin C and more calcium than Spirulina, supporting immune function and bone health.

Vitamin C prevents scurvy, and calcium strengthens bones. Chlorella provides these nutrients, whereas Spirulina lacks vitamin C and has less calcium.

(c)(iii) Ans: citrus fruit / (named) fruit / (named) vegetable

Oranges, lemons, and bell peppers are rich in vitamin C, essential for collagen synthesis and immunity.

(d)(i) Ans: Proteins act as carriers in membranes, enabling active transport of molecules against their concentration gradient using energy (ATP).

Carrier proteins bind and transport specific molecules, ensuring selective uptake of nutrients.

(d)(ii) Ans: amino acids

Proteins are polymers of amino acids linked by peptide bonds, forming diverse structures for biological functions.

Question

A new species of frog was discovered in 2009 in the Amazon rainforest in Peru.
Fig. 6.1 shows this frog, Osteocephalus castaneicola.

(a) State the genus of this animal. [1]
In the past, anatomy was a way to classify species. DNA is now used to aid the classification of
organisms.
(b) (i) Draw and annotate a diagram to show the structure of DNA.

(ii) Describe how DNA can be used to classify organisms. [2]
(c) DNA controls cell function by controlling the production of proteins.
(i) Proteins are coded for by a length of DNA.
What is the name given to the length of DNA which codes for a protein? [1]
(ii) Describe the role of mRNA in protein synthesis. [3]
[Total: 10]

Answer/Explanation

Ans

6 (a) Osteocephalus ;

(b) (i) 1 two strands twisted to form helix ;
2 cross-links between the strands ;
3 A joins with T/C joins with G ;
4 all labels correct ;

(ii) the sequence of bases in DNA are used ;
base sequences /DNA/ genes, that are more similar mean that organisms are
more closely related ; ORA

(ii) 1 mRNA carries a copy of the gene/DNA/ base pair sequence ;
2 mRNA travel from the nucleus ;
3 to the ribosome/ cytoplasm ;
4 order of amino acids depends on the sequence of bases in mRNA/AW ;

Question

Vertebrate animals are grouped into a number of classes.
Complete the sentences by naming each of the vertebrate classes that are described.

Answer/Explanation

Ans:

Question

Fig. 1.1 shows a woodlouse.

The woodlouse is a crustacean, one of the four groups of arthropod.
It is a herbivore that lives on land and eats decaying plant materials.
It breathes with gills that must be kept moist.
(a) Name two other groups of arthropod.
For each group state one feature found only in animals of that group.

(b) Some students were sent to find woodlice for an investigation.
Suggest and explain two reasons why populations of woodlice are usually found under
stones, decaying wood and leaves.

Answer/Explanation

Ans:

Question

Fig. 1.1 shows a snake.

A snake is a living organism and so shows the characteristics of life.
The snake feeds by catching small animals such as mice and rats

Fig. 1.1

(a) Complete Table 1.1 showing some of the characteristics of life for the snake.

Answer/Explanation

Ans:

(b) The snake is a reptile.
State one way that a reptile differs from a fish.Ans: (reptiles)
do not have gills or fins / have legs / have lungs / can live on
land / lay shelled eggs / cannot live under water / AVP;

iGCSE Biology (0610) 1.3 Features of organisms iGCSE Style Questions Paper 4

Question

Resources

Members

Company