The stages in the binary fission of Amoeba are shown above.
(a) Arrange the stages in their proper natural sequence in binary fission.
(b) How does this differ from the process of sporulation employed by Amoeba?

Identify the types of gametes and give an example for each of A, Band C shown in tbe diagram, given below.

These pictures show the gynoecium of A. Papaver and B. Michelia.
(a) Write one similarity and one difference between the two.
(b) Name the three parts of a pistil.

Identify the types of flowers A and B on the Commelina plant shown above.
(b) Mention the type(s) of pollination that can occur in each of them.

A Human Spermatozoan
A diagrammatic sketch of a human sperm is given. Identify the parts labelled A, Band C and mention their respective functions.

The events in a menstrual cycle are represented above. Answer the following questions based on that.
(a) Why is the phase between 5^th and 15^th day of menstrual cycle, called
(i) proliferative phase?
(ii) follicular phase?
(b) Mention the ovarian events during the luteal phase.

(a) Name the human embryonic stage shown above.
(b) Identify 'a' and 'b' in it.
(c) Where are stem cells located in it?
(d) Mention the role of 'b'.

Shown above is the surgical method of contraception in human males.
Answer the following questions:
(a) Give the technical term for the process shown above.
(b) What is the principle behind it as a contraceptive method?
(c) How is the process carried out?

ABO blood group character in human population exhibits four possible phenotypes and six different genotypes. Explain the different mechanisms of inheritance involved in exhibiting the possibility of four phenotypes and six genotypes.

Given below is a table showing the genotypes and the phenotypes of blood groups in the human population.

(i) Identity the genotypes (W) and (X) and the phenotypes (Y) and (Z).
(ii) How is codominance different from incomplete dominance and dominance?
(iii) Name the pattern of inheritance exhibited by the phenotypes Y and Z given in the table.

Study the pedigree chart showing the pattern of inheritance of blood group character in a family.

(a) Give the genotypes of the parents in generation I.
(b) State the possible genotypes of the individuals.
(i) X in generation II.
(ii) Y in generation III.
(c) How does the inheritance of this blood group explain codominance?

Haemophilia is a sex-linked recessive disorder in humans. The pedigree chart given below shows the inheritance pattern of haemophilia in a family. Study the inheritance pattern and answer the questions that follow:

(a) Give the possible genotypes of the members 4 and 5 in the above chart.
(b) A blood test shows that the member 14 is a carrier of haemophilia. The member 15 has recently married the member 14. What is the probability of their first child being haemophilic? Show it with the help of a Punnett square.

A DNA replication fork is shown above. Answer the following questions based on that.
(i) Why does DNA replication occur in such small forks?
(ii) What is a synthesis and b synthesis?
(iii) Mention the polarity at A and B.

Lac operon in the 'switched on' position is shown above.
(a) Identify the molecule A and the enzymes B, C and D in the diagram.
(b) When will this operon get 'switched off'?

(a) State the hypothesis which S.L. Miller tried to prove in the laboratory with the help of the set up given above.
(b) Name the organic compound observed by him in the liquid water after running the above experiment.
(c) A scientist simulated a similar set up and added CH₄, NH₃ and water vapour at 800°C.
Which important component is missing in his experiment?