How many eggs do you think were released by the ovary of a female dog which gave birth to 6 puppies?
Solution and Explanation
Top Questions on Human Reproduction
Study the graphs given below for Case 1 and Case 2 showing different levels of certain hormones and answer the question that follows:
(a) Which hormone is responsible for the peak observed in Case 1 and Case 2? Write one function of that hormone.
(b) Write changes that take place in the ovary and uterus during follicular phase.
Student to attempt either sub-part (c) or (d):
(c) Name the hormone Q of Case 2. Write one function of hormone Q.
OR
(d) Which structure in the ovary will remain functional in Case 2? How is it formed?- CBSE CLASS XII - 2025
- Biology
- Human Reproduction
- Shyam and Radha are expecting their first child with Radha being in her second month of pregnancy with no complications. Shyam’s family has a history of cystic fibrosis while Radha’s family has a history of Down’s syndrome, leading to a concern that the baby may have one of these conditions.
(a) Suggest and explain a way of testing if their baby is at risk for any genetic disorders.
(b) In case of presence of one or both of the abnormalities and posing a risk to the mother’s health, mention one possible option for them to consider. Is that option safe for Radha at the current gestational age? Justify.
(c) Under what conditions is the process mentioned in (b) illegal?- CBSE CLASS XII - 2025
- Biology
- Human Reproduction
- Assertion (A): Saheli is the World’s first non-steroidal oral contraceptive pill.
Reason (R): It has been developed by National Institute of Immunology, New Delhi.- CBSE CLASS XII - 2025
- Biology
- Human Reproduction
Match the following items of Column-I with that of Column-II:
- CBSE CLASS XII - 2025
- Biology
- Human Reproduction
- "Sex of a newborn baby in humans depends on the father, not the mother." Confirm this statement with the help of a flow chart.
- CBSE Compartment X - 2025
- Science
- Human Reproduction
Questions Asked in CBSE CLASS XII exam
Bittu and Chintu were partners in a firm sharing profit and losses in the ratio of 4 : 3. Their Balance Sheet as at 31st March, 2024 was as follows:
On 1st April, 2024, Diya was admitted in the firm for \( \frac{1}{7} \)th share in the profits on the following terms:- (i) New profit sharing ratio between Bittu, Chintu and Diya was 3 : 3 : 1 .
- (ii) Fixed Assets were found to be overvalued by ₹ 1,40,000.
- (iii) Creditors were paid ₹ 4,20,000 in full settlement.
- (iv) Diya brought proportionate capital and ₹ 5,60,000 as her share of goodwill premium by cheque.
Prepare Revaluation Account and Partners' Capital Accounts.
- CBSE CLASS XII - 2025
- Partnership Accounts
- Pass the necessary journal entries for the following transactions on the dissolution of a partnership firm of Vibha and Ajit after various assets (other than cash) and external liabilities have been transferred to Realisation Account:}
Creditors worth ₹ 46,000 accepted ₹ 9,000 cash and furniture of ₹ 32,000 in full settlement of their claim.
The firm had stock of ₹ 20,000. Ajit took over 40% of the stock at a discount of 10% while the remaining stock was sold for ₹ 18,000.
Vibha was appointed to look after dissolution work for which she was allowed a remuneration of ₹ 16,000. Vibha agreed to bear the dissolution expenses. Actual dissolution expenses ₹ 15,000 were paid by Vibha.
Ajit’s loan of ₹ 45,000 was settled at ₹ 42,000.
A machine which was not recorded in the books was taken over by Vibha at ₹ 23,000, whereas its expected value was ₹ 28,000.
The firm had a debit balance of ₹ 20,000 in the Profit and Loss Account on the date of dissolution.- CBSE CLASS XII - 2025
- Dissolution of Partnership Firms
- How does the process of Natural Selection affect Hardy-Weinberg equilibrium? Explain with the help of graphs.
- CBSE CLASS XII - 2025
- evolution
- A battery of emf \( E \) and internal resistance \( r \) is connected to a rheostat. When a current of 2A is drawn from the battery, the potential difference across the rheostat is 5V. The potential difference becomes 4V when a current of 4A is drawn from the battery. Calculate the value of \( E \) and \( r \).
- CBSE CLASS XII - 2025
- Current electricity
- An electric dipole of dipole moment \( 1.0 \times 10^{-12} \ \text{Cm} \) lies along the x-axis. An electric field of magnitude \( 2.0 \times 10^4 \ \text{NC}^{-1} \) is switched on at an instant in the region. The unit vector along the electric field is \( \frac{\sqrt{3}}{2} \hat{i} + \frac{1}{2} \hat{j} \). The magnitude of the torque acting on the dipole at that instant is:
Concepts Used:
Gametogenesis
The gametogenesis process includes the formation of reproductive cells or sex cells in living organisms. In plants, it is carried throughout mitosis whereas, in animals, it is carried through meiosis. The formation of male and female gametes are the two basic steps that take place during the gametogenesis process.
Based on the living organism, the process of gametogenesis occurs in:-
Plants: It occurs by the meiotic division of diploid gametocytes. In higher plants, it happens along with sporogenesis.
Animals: It occurs by meiosis where gametes are formed from their diploid mother cells exist in organs called gonads.
Stages of Gametogenesis
The gametogenesis process occurs in three steps. They are as follows;
- Mitotic divisions together with cell growth of precursor germ cells.
- The happening of Meiosis I and Meiosis II for producing haploid daughter cells.
- Metamorphose haploid daughter cells for the production of functional gametes.