Give reasons for the following: (a) Adrenal gland is known as the stress gland of the body. (b) Prenatal sex determination is banned in India. (c) Vegetative propagation is advantageous in some plants.
Fission and fragmentation
High importanceUsually 3 marks a paper · mostly MCQs and long answers · asked in 4 of the last papers
Notes are being written
The board questions below are real and complete — they come from the CBSE papers themselves. The written notes for this topic are still being prepared.
Board questions on this topic
7 from the CBSE papers we hold — the exact wording the board used.
Assertion (A): Variations are not often seen in off-springs produced by asexual reproduction. Reason (R): DNA molecule generated by replication is not similar to the original DNA.
- (a) Both Assertion
- (b) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
- (c) Both Assertion
- (d) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- (e) Assertion
- (f) is true, but Reason (R) is false.
- (g) Assertion
- (h) is false, but Reason (R) is true.
Draw labelled diagrams to show different stages of budding in Hydra.
In which of the following organisms, multiple fission is a means of asexual reproduction?
- (a) Yeast
- (b) Leishmania
- (c) Paramoecium
- (d) Plasmodium
(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.
Select the INCORRECT match (between the plant and its vegetative part) from the following:
- (a) Bryophyllum, leaf
- (b) Potato, stem
- (c) Money-plant, stem
- (d) Rose, root
Which one of the two multicellular organisms - Spirogyra and Planaria reproduces by regeneration and why? Give an example of any other organism which can also reproduce by the same process.