Tag: reproductive systems

Questions Related to reproductive systems

How does the sperm break through the egg cell membrane? Choose the option you think is right.

  1. Tears a hole in the membrane

  2. Dissolves the membrane with chemicals

  3. Bites through the membrane with teeth

  4. Squeezes through gaps in the membrane


Correct Option: A

During the development of embryo which of the following occur first 

  1. Differentiation of tissue

  2. Differentiation of cells

  3. Differentiation of organs

  4. Differentiation of organ system


Correct Option: B
Explanation:

Blastula differentiate into various regions and cells (blastomeres) of a particular region form a particular part of adult body, hence these areas are called presumptive areas and at this stage if cells of a particular area removed the adult lacks a particular part from its body.

Which distinguishes a morula from a blastula 

  1. Presence of more yolk

  2. Absence of yolk

  3. Presence of a cavity

  4. Absence of a cavity


Correct Option: D
Explanation:

In microlecithal eggs or alecithal eggs, the cleavage results in the production of closely packed blastomeres. The stage in which solid mass of blastomeres appears is said to be morula, whereas blastula is hollow with a cavity known as blastocoel.

The events in sexual reproduction are
(i) pre-fertilisation
(ii) fertilisation
(iii) post-fertilisation
The sequential order of their occurence is

  1. (ii) - (i) - (i)

  2. (ii) - (ii) - (i)

  3. (i) - (ii) - (iii)

  4. (i) - (iii) - (iv)


Correct Option: C
Explanation:

In spite of their morphological, anatomical and physiological differences, the fundamental events in sexual reproduction are the same. These events can be categorized as follows:

1. Pre-fertilization events: All the preparatory events which occur before the fusion of gametes are called pre-fertilization events. These include Gametogenesis and gamete transfer.
2. Fertilization: Fusion of two entire gametes ( one male and another female) to form a zygote.
3. Post-fertilization: All the events that occur during sexual reproduction after the fusion of gametes are called post-fertilization events.
So, the correct answer is '(i)-(ii)- (iii)'.

Match column I with column II and select the correct options from the codes given.

Column I Column II
A. Hypothalamus (i) Sperm lysins
B. Acrosome (ii) Estrogen
C. Graafian follicle (iii) Relaxin
D. Leydig's cells (iv) GnRH
E. Parturition (v) Testosterone
  1. A - (iv), B - (i), C - (ii), D - (iii), E - (v)

  2. A - (ii), B - (i), C - (iv), D - (iii), E - (v)

  3. A - (ii), B - (i), C - (v), D - (iv), E - (iii)

  4. A - (iv), B - (i), C - (ii), D - (v), E - (iii)


Correct Option: D
Explanation:

The hypothalamus is a small region of the brain. It's located at the base of the brain, near the pituitary gland. It secretes hypothalamic hormone such as the GnRH or Gonadotropin stimulating hormone which further has effects on the pituitary gland. The acrosome is the anterior covering on the head of the sperm that consists of enzymes called lysins that can lyse the ovum membrane to penetrate and fertilize it. A Graafian follicle is a developed tertiary follicle and is responsible for the ovulation that occurs as a result of the surge in FSH and LH levels responsible for estrogen production. Leydig cells in the seminiferous tubules are responsible for the secretion of androgens such as testosterone. Parturition is the process of the delivery of the fetus and during this process, Relaxin is a hormone produced by the ovary and the placenta with important effects in the female reproductive system and during pregnancy. 

So, the correct option is 'A - (iv), B - (i), C - (ii), D - (v), E - (iii)'.

Match column I (terms) with column II (definitions) and select the correct options from the codes given.

Column I Column II
A. Parturition (i) Attachment of embryo to endometrium
B. Gestation (ii) Release of egg from Graafian follicle
C. Ovulation (iii) Delivery of baby from uterus
D. Implantation (iv) Duration between pregnancy and birth
E. Conception (v) Formation of zygote by fusion of the egg and sperm
(vi) Stoppage of ovulation and menstruation
  1. A - (ii), B - (iv), C - (i), D - (v), E - (vi)

  2. A - (iv), B - (iii), C - (i), D - (v), E - (ii)

  3. A - (v), B - (vi), C - (ii), D - (iii), E - (iv)

  4. A - (iii), B - (iv), C - (ii), D - (i), E - (v)


Correct Option: D
Explanation:

Parturition is the delivery or childbirth of baby from the uterus. Gestation is the period of development during the carrying of an embryo or fetus inside viviparous animals and the duration between pregnancy and birth. Ovulation is the process of release of the ovum from the Graafian follicle as it ruptures. Implantation is the process of attachment of the zygote to the endometrial lining of the uterus. Conception refers to the post-fertilization fusion of the egg and sperm into the zygote.

So, the correct option is 'A - (iii), B - (iv), C - (ii), D - (i), E - (v)'.