The fluid-filled cavities near the embryonic ectoderm and the embryonic endoderm are respectively:
1. amniotic cavity, blastocele
2. amniotic cavity, yolk sac
3. blastocele, amniotic cavity
4. yolk sac, amniotic cavity
During embryonic development:
1. | the trophoblast cells help in the formation of the placenta and inner cell mass differentiates into the embryo |
2. | the trophoblast cells differentiate into the embryo and inner cell mass helps in the formation of the placenta |
3. | the trophoblast cells help in the formation of the placenta and both trophoblast cells and inner cell mass differentiate into the embryo |
4. | the trophoblast cells help in the formation of the placenta and differentiate into the embryo as well |
Before the placenta takes over, what structure secretes large amounts of progesterone to support pregnancy?
1. | Corpus Albicans | 2. | Graafian follicle |
3. | Chorion | 4. | Corpus luteum |
The cleavage divisions in the human embryo may be best described as:
1. | Holoblastic, Equal, Indeterminate, Radial |
2. | Holoblastic, Unequal, Indeterminate, Radial |
3. | Holoblastic, Equal, Indeterminate, Spiral |
4. | Meroblastic, Equal, Indeterminate, Spiral |
Chorion in terrestrial vertebrate embryos:
1. | prevents desiccation of the embryo |
2. | helps in the exchange of oxygen and carbon dioxide with the environment |
3. | perform excretory functions |
4. | acts as a shock absorber |
Erythropoiesis in the earliest days of gestation is the function of:
1. | yolk sac | 2. | chorion |
3. | fetal bone marrow | 4. | amnion |
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R).
Assertion (A): | All mammalian embryos will develop into females unless a functional SRY gene is present. |
Reason (R): | SRY gene is non-functional in a female zygote. |
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. |
Which one of the following statements with regard to embryonic development in humans is correct?
1. | Cleavage divisions bring about a considerable increase in the mass of protoplasm. |
2. | In the second cleavage division, one of the two blastomeres usually divides a little sooner than the second. |
3. | With more cleavage divisions, the resultant blastomeres become larger and larger. |
4. | Cleavage division results in a hollow ball of cells called morula. |
The formation of the three embryonic germ layers is called:
1. | morulation | 2. | blastulation |
3. | neurulation | 4. | gastrulation |
In the given diagram showing a blastocyst in human embryonic development:
I: | Both 3 and 5 are parts of inner cell mass and contribute to the embryo |
II: | 4 becomes the future amniotic cavity and prevents desiccation of the embryo |
III. | 2 is the outer cell mass and contributes to the placenta and ectoderm of the embryo |
1. | Only I is correct |
2. | Only I and III are correct |
3. | Only I and II are incorrect |
4. | I, II, and III are incorrect |