I: | Secondary oocyte is fertilized by the sperm. |
II: | At fertilization, the secondary oocyte completes Meiosis-II |
(i) | Relaxin is secreted by the ovary in the later phase of pregnancy. |
(ii) | Inner cell mass differentiates into ectoderm and endoderm just before implantation. |
(iii) | Implantation leads to pregnancy. |
(iv) | Embryo with 8 to 16 blastomeres is called morula. |
Assertion(A): | Holoblastic cleavage with almost equal sized blastomeres is a characteristics of placental animals. |
Reason(R): | Eggs of most mammals including humans are of centrolecithal type. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |