✓ Board-verified
Science · 2024 · 5 marks
CBSE 2024 · Region 1 · Set 1 · Q35
(A) (i) Name three techniques/devices used by human females to avoid pregnancy. Mention the side effects caused by each. (ii) What will happen if in…
(A)(i)
Name three techniques/devices used by human females to avoid pregnancy. Mention the side effects caused by each.
(ii)
What will happen if in a human female (a) fertilisation takes place, (b) an egg is not fertilised ?
OR
(B)(i)
Draw a diagram showing spore formation in Rhizopus and label the (a) reproductive and (b) non-reproductive parts. Why does Rhizopus not multiply on a dry slice of bread ?
(ii)
Name and explain the process by which reproduction takes place in Hydra.
Marking-scheme solution
(A) (i)
Chemical Method/Oral pills Side effects: Change the hormonal balance of the body.
(a) Reproductive part - Sporangia
(b) Non-reproductive part - Hypha/Hyphae.
Dry slice of bread does not provide moisture and nutrients necessary for the germination and multiplication of Rhizopus.
(ii)
Alternate answer:Budding:
Hydra uses regenerative cells for reproduction. A bud develops as an outgrowth due to repeated cell division at one specific site and develop into tiny individuals. On maturation, these buds detach from the parent and become new individuals.
Regeneration:
It is carried out by specialised cells. If hydra is cut or broken into many pieces, many of these pieces grow into separate individuals.
[All How do Organisms Reproduce? questions2024 question paperNCERT solutions: How do Organisms Reproduce?Practice How do Organisms Reproduce? →
More from How do Organisms Reproduce?
- In the following figure showing a germinating gram seed, name the parts labelled as A, B and C: Why is part ' B ' considered to be important during…2022
- Explain the events that take place once a sperm reaches the oviduct till it becomes a foetus. Write the role of placenta in pregnancy.2024
- Differentiate between self-pollination and cross pollination. Which one of the two is better for the survival of species? Give reason to justify your…2025
- The number of chromosomes in parents and offspring of a particular species undergoing sexual reproduction remains constant due to:2026
- Assertion: Offsprings produced by asexual reproduction are genetically similar to the parents. Reason (R): Asexual reproduction involves a single…2024
- Yeast multiplies by which of the following methods?2026
- (i) Where are testes located in the human males and why? State two function of the testes. (ii) In the human female, one of the ovaries releases an…2023
- Which one of the two multicellular organisms - Spirogyra and Planaria reproduces by regeneration and why? Give an example of any other organism which…2022
CBSE Class 10 Science past-paper question from the 2024 board exam, with the answer as CBSE’s own marking scheme gives it. Where our answers come from.