CIE iGCSE Co-Ordinated Science B15.4 Sexual reproduction in humans Exam Style Questions Paper 3
Question
(a) Fig. 1.1 is a diagram of the male reproductive system in humans.
(i) State the letter from Fig. 1.1 that identifies the part that:
carries urine and semen ………………………………
produces sperm ………………………………
transfers sperm to the urethra. ………………………………
(ii) Draw an X on Fig. 1.1 to identify the position of the prostate gland.
(b) Sperm cells are the male gametes in humans.
Sperm cells are 0.05 mm in length.
Female gametes are 0.1 mm in length.
(i) State the name of the female gametes in humans.
(ii) Calculate how many times longer female gametes are than male gametes.
(c) Sperm cells have a high rate of respiration.
(i) State the word equation for aerobic respiration.
(ii) Complete the sentence about respiration.
Respiration releases the ……………………………… needed for cell division and movement.
(d) Sperm cells are involved in fertilisation.
Describe the process of fertilisation in humans.
Include the site of fertilisation in your answer.
▶️Answer/Explanation
Ans : 1(a)(i) B ;
D ;
A ;
1(a)(ii) X drawn on prostate gland ;
1(b)(i) egg / ova / ovum ;
1(b)(ii) (0.1 / 0.05 =) 2 ;
1(c)(i) glucose + oxygen → carbon dioxide + water
1 mark for reactants ;
1 mark for products ;
1(c)(ii) energy ;
1(d) fusion of the, sperm / male gamete, and, egg / female gamete ;
ref to nuclei ;
fertilisation takes place in the oviduct ;
Question
(a) Fig. 4.1 is a diagram of the female reproductive system in humans.
The boxes on the left show the letters of some of the parts in Fig. 4.1.
The boxes on the right show some functions.
Draw one line from each letter to its function.
(b) A survey records the length of the menstrual cycle in a sample of females.
Fig. 4.2 shows a bar chart of the results.
(i) State the most frequent length of the menstrual cycle shown in Fig. 4.2.
………………………………….
(ii) State the number of females that have a 26‐day menstrual cycle shown in Fig. 4.2.
………………………………….
(c) State the name of the female gamete in humans.
……………………………………………………………………………………………………………………………
(d) The list shows several processes that occur before the development and birth of a baby.
Put the stages in the correct order.
Two have been done for you.
fertilisation
formation of embryo
formation of zygote
implantation
release of female gamete
(e) State where fertilisation occurs in plants.
……………………………………………………………………………………………………………………………
▶️Answer/Explanation
Ans: 4(a)
4(b)(i) 27 (days) ;
4(b)(ii) 9 ;
4(c) egg / ovum ;
4(d) release of female gamete
fertilisation
formation of zygote
formation of embryo
implantation
1 or 2 correct ;
3 correct ;
4(e) ovule ;
Question
(a) Fig. 1.1 is a diagram of the female reproductive system in humans.
Identify the letters in Fig. 1.1 that represent the part:
that produces female gametes …………………….
that receives the penis during sexual intercourse …………………….
where fertilisation occurs. …………………….
(b) State the names of the female gametes and the male gametes in humans.
female gametes ………………………………………..
male gametes ………………………………………..
(c) Gametes are cells.
Draw and label the main structures in a simple animal cell in the space provided.
(d) Circle the correct word or phrase in bold in each sentence to describe early development in humans.
During fertilisation, the nuclei of gametes fuse forming a fertilised cell called a fetus / a zygote / an embryo.
This divides to form a zygote / an embryo / an ovule which is a ball of cells.
This ball of cells implants into the wall of the cervix / uterus / vagina.
▶️Answer/Explanation
Ans: 1(a) B ;
D ;
A ;
1(b) female – ovum / egg ;
male – sperm ;
1(c) cell membrane drawn correctly and labelled ;
nucleus drawn correctly and labelled ;
space around nucleus inside of the cell membrane labelled cytoplasm ;
1(d) a zygote ;
an embryo ;
uterus ;
Question
(a) Reproduction is one of the characteristics of living things.
Complete the definition.
Reproduction is the process that makes more of the same kind of …………………………………
(b) Fig. 1.1 is a diagram of the male reproductive system in humans.
The boxes on the left show the letters labelling some of the parts in Fig. 1.1.
The boxes on the right show functions of some of the parts.
Draw one line to link each letter to its function.
(c) Fig. 1.2 is a drawing of a sperm cell.
Label the cell structure that contains the genetic material with a label line and the correct name.
(d) State the names of two cell structures that are present in plant cells but not present in animal cells.
1 ………………………………………………………………………………………………………………………………
2 ………………………………………………………………………………………………………………………………
▶️Answer/Explanation
Ans: 1(a) organism ;
1 mark for each line ;;;
1(b)
1(c) nucleus correctly labelled
labelling correct structure ;
correct name ;
1(d) any two from:
chloroplast ;
cell wall ;
(permanent) vacuole ;
Question
(a) Fig. 1.1 is a diagram of a flower.
State the letter in Fig. 1.1 that identifies the part:
that attracts insects …………………..
that produces pollen ……………………
where fertilisation occurs. ……………………
(b) State the name of the part in the human body where fertilisation takes place.
(c) Some plants reproduce both asexually and sexually.
Table 1.1 compares some of the features of asexual reproduction and sexual reproduction.
Place ticks (3) in the boxes in Table 1.1 to show the correct features of asexual reproduction and sexual reproduction.
(d) Bacteria reproduce by a type of asexual reproduction.
Fig. 1.2 is a diagram of the reproduction of a bacterium.
The original bacterium divides to form two bacteria.
A bacterium can divide every 30 minutes.
Calculate the number of bacteria after 4 hours if you start with one bacterium.
(e) Reproduction is one of the characteristics of living organisms.
State three other characteristics of living organisms.
1 …………………………………………………………………………
2 …………………………………………………………………………
3 …………………………………………………………………………
▶️Answer/Explanation
Ans : 1(a) A ;
E ;
C ;
1(b) oviduct ;
1(c) 
1(d) ref to 8 divisions ;
28 = 256 ;
1(e) any three from:
movement ;
respiration ;
sensitivity ;
growth ;
excretion ;
nutrition ;
Question
(a) Albinism is a condition in humans where no pigment is made by the skin.
The allele for no albinism is dominant and represented by the letter A.
The allele for albinism is recessive and represented by the letter a.
(i) Table 4.1 shows some genotypes, phenotypes and descriptions of the genotypes for three people.
Complete Table 4.1.
(ii) Person 2 and person 3 have a child together.
Complete the Punnett square diagram in Fig. 4.1 to show the possible genotypes of the offspring.
(b) Chromosomes carry genetic information.
(i) Complete the definition of the term chromosome.
A chromosome is a thread-like structure of …………………………… ,
carrying genetic information in the form of …………………………… .
(ii) State where chromosomes are found in human cells.
(iii) State the sex chromosomes found in male gametes in humans.
……………………………… or ………………………………
(c) State the name of the male gametes in humans.
(d) State the name of the organ where male gametes are produced in humans.
▶️Answer/Explanation
Ans : 4(a)(i) 
4(a)(ii) 
4(b)(i) DNA ;
genes ;
4(b)(ii) nucleus ;
4(b)(iii) X and Y ;
4(c) sperm ;
4(d) testes ;
Question
(a) A student investigates the germination of pea seeds. (Sub-topic – B3.1)
The student places pea seeds in test-tubes with different conditions and records whether the seeds germinate.
Table 1.1 shows the conditions for each test-tube.
| Test-tube | water present? | oxygen present? |
|---|---|---|
| A | yes | yes |
| B | yes | no |
| C | no | no |
| D | no | yes |
(i) Predict in which test-tube the pea seeds will germinate.
▶️Answer/Explanation
A
Explanation:
Germination requires both water and oxygen. Therefore, the seeds will germinate in test-tube A, where both water and oxygen are present.
(ii) State one other requirement for germination that is not tested in Table 1.1.
▶️Answer/Explanation
suitable temperature
(b) After the seeds germinate, the plant photosynthesizes. (Sub-topic – B6.1)
(i) Complete the sentence to define photosynthesis.
▶️Answer/Explanation
carbohydrates; light
(ii) State the two raw materials needed for photosynthesis.
▶️Answer/Explanation
carbon dioxide; water
(c) Peas contain protein. (Sub-topic – B4.1)
State the name of the smaller molecules from which protein is made.
▶️Answer/Explanation
Proteins are made from smaller molecules called amino acids.
Question
(a) Fig. 10.1 is a diagram of an insect-pollinated flower.
(i) On Fig. 10.1:
• circle the part where pollination occurs,
• draw an X on the part where fertilisation occurs,
• identify one part that produces pollen with a label line and the correct name.
(ii) State the names of two parts of the carpel.
1 ……………………………………………………………………………………………………………………….
2 ……………………………………………………………………………………………………………………….
(iii) Describe the function of the petals.
………………………………………………………………………………………………………………………….
………………………………………………………………………………………………………………………….
(b) The sentences describe fertilisation and early development in humans.
Circle the word in bold that makes each sentence correct.
Fertilisation occurs in the ovary / oviduct / vagina.
The nuclei of a sperm and egg fuse to form a gamete / tissue / zygote.
The fertilised cell divides into a ball of cells called an embryo / organ / ovule.
The ball of cells implants into the wall of the cervix / uterus / vagina.
▶️Answer/Explanation
Ans: 10(a)(i)
Question
Scientists measure the length of sperm cells from different animals. The animals are placed in size from animal A (the smallest) to animal F (the largest). Fig. 1.1 shows the results.
(i) Using Fig. 1.1, state the length of a sperm cell in animal B.
(ii) State the animal with the shortest length of sperm.
(iii) State evidence from Fig. 1.1 that shows that the length of sperm does not increase with the size of the animal.
▶️Answer/Explanation
(i) 0.12 mm ;
(ii) A ;
(iii) animal F is the biggest but does not have the longest length of sperm / animal D has the longest sperm but is not the biggest animal / avp ;
Question (b)
Plant and animal cells both contain a nucleus.
Name two other structures seen in both plant and animal cells.
▶️Answer/Explanation
any two from:
cell membrane ;
cytoplasm ;
AVP ; e.g. ribosomes / mitochondria
Question (c)
The boxes on the left show some of the parts of a plant cell. The boxes on the right show the functions of the parts. Draw lines to link each part with its function.
Parts of Plant Cell:
- Cell wall
- Chloroplast
- Nucleus
- Vacuole
Functions:
- Contains genetic material
- Contains cell sap and supports the cell
- Site of photosynthesis
- Strengthens the cell
▶️Answer/Explanation
Question (d)
Substances enter and leave cells. Name the process by which substances enter the cells.
▶️Answer/Explanation
The process by which substances enter the cells is diffusion.
Detailed Solution:
Diffusion is the process by which substances move from an area of higher concentration to an area of lower concentration across a semi-permeable membrane (e.g., the cell membrane). This process is passive and does not require energy. It is essential for the movement of gases (e.g., oxygen and carbon dioxide) and small molecules into and out of cells.
Question (e)
Explain why muscle cells need high rates of respiration.
▶️Answer/Explanation
Muscle cells need high rates of respiration because:
- Respiration releases energy, which is required for muscle contraction and movement.
- Muscle cells are highly active and require a continuous supply of energy to perform their functions.
Detailed Solution:
Muscle cells are highly specialized for movement and require a significant amount of energy to contract and relax. This energy is provided through the process of respiration, which converts glucose and oxygen into ATP (adenosine triphosphate), the energy currency of the cell. High rates of respiration ensure that muscle cells have a constant supply of ATP to meet their energy demands, especially during physical activity or exercise.
Question
(a) Fig. 4.1 is a diagram of the male reproductive system in humans.
Identify the letter from Fig. 4.1 that represents the:
- part where sperm is produced
- part which secretes the fluid that sperm swim in
- tube which carries both semen and urine
▶️Answer/Explanation
Answer:
1. E (Testes)
2. C (Seminal vesicle)
3. A (Urethra)
Explanation:
– The testes (E) are responsible for producing sperm.
– The seminal vesicle (C) secretes a fluid that mixes with sperm to form semen.
– The urethra (A) is the tube that carries both semen and urine out of the body.
(b) State the name of the part of the female reproductive system that releases gametes.
▶️Answer/Explanation
Answer:
Ovary
Explanation:
The ovary is the part of the female reproductive system that releases gametes (eggs) during ovulation.
(c) The statements in Table 4.1 describe either asexual or sexual reproduction.
Complete Table 4.1 to identify the type of reproduction each statement describes.
| Statement | Type of Reproduction |
|---|---|
| Offspring are genetically identical to each other | …… |
| Produces zygotes | …… |
| Involves the fusion of nuclei | …… |
▶️Answer/Explanation
Answer:
| Statement | Type of Reproduction |
|---|---|
| Offspring are genetically identical to each other | Asexual |
| Produces zygotes | Sexual |
| Involves the fusion of nuclei | Sexual |
Explanation:
– Asexual reproduction produces offspring that are genetically identical to each other because there is no fusion of gametes.
– Sexual reproduction involves the fusion of male and female gametes to form a zygote, which develops into a new organism.
(d) Fig. 4.2 is a diagram representing the reproduction of a type of organism called a hydra.
Identify if this organism is reproducing asexually or sexually. Use evidence from Fig. 4.2 to give a reason for your answer.
Type of reproduction
Reason
▶️Answer/Explanation
Answer:
Type of reproduction: Asexual
Reason: Offspring are produced by only one parent.
Explanation:
In asexual reproduction, offspring are produced from a single parent without the fusion of gametes. The diagram shows a hydra producing a bud, which is a form of asexual reproduction.
(e) Reproduction and respiration are characteristics of living things.
State two other characteristics of living things.
▶️Answer/Explanation
Answer:
1. Movement
2. Growth
Explanation:
– Movement is a characteristic of living things, as organisms can move to find food, escape predators, or respond to stimuli.
– Growth is another characteristic, as living organisms increase in size and complexity over time.
Question
(a) Fig. 1.1 is a diagram of the female reproductive system.
(i) State the letter from Fig. 1.1 that shows the part where:
- fertilisation occurs
- gametes are produced.
▶️Answer/Explanation
- Fertilisation occurs: A
- Gametes are produced: E
Explanation: Fertilisation typically occurs in the oviduct (fallopian tube), which is labelled as A in the diagram. Gametes (eggs) are produced in the ovaries, labelled as E.
(ii) Identify the part labelled B in Fig. 1.1.
▶️Answer/Explanation
The part labelled B is the uterus.
Explanation: The uterus is the organ where the fertilised egg implants and develops during pregnancy.
(b) Below information shows a student’s description of fertilisation in humans.
The description of fertilisation in humans is incorrect.
Circle the two incorrect words in the description in Fig. 1.2.
| Fertilisation is the separation of the nuclei from a sperm cell and an ovary cell. |
▶️Answer/Explanation
The two incorrect words are separation and ovary.
Explanation: Fertilisation is the fusion (not separation) of the nuclei from a sperm cell and an egg cell (not ovary cell).
(c) Fig. 1.3 shows how the thickness of the uterus lining changes during the menstrual cycle.
Table 1.1 represents the days during an average menstrual cycle.
Use Fig. 1.3 and your own knowledge to:
(i) Place ticks (✓) in Table 1.1 to show the days when the uterus lining is shed.
▶️Answer/Explanation
Ticks should be placed under days 1–4.
Explanation: The uterus lining is shed during the menstrual phase, which typically occurs in the first few days of the menstrual cycle.
(ii) Place crosses (×) in Table 1.1 to show the days when the uterus lining is at its thickest.
▶️Answer/Explanation
Crosses should be placed under days 24–26.
Explanation: The uterus lining is at its thickest just before menstruation begins, typically around days 24–26 of the menstrual cycle.
(d) Complete the sentence to define the term reproduction.
Reproduction is the processes that make …… of the same …… of organism.
▶️Answer/Explanation
Reproduction is the processes that make more of the same kind of organism.
Explanation: Reproduction is the biological process by which new individuals of the same species are produced, ensuring the continuation of the species.