Tag: fertilization in humans

Questions Related to fertilization in humans

Passage of ova through female reproductive tract is facilitated by 

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. Ciliary movement

  2. Amoeboid movement

  3. Flagellar movement

  4. Cyclosis

Show answer
Correct Option: A
Explanation:

The fallopian cells have cells lined with small hair-like structures called cilia that enable movement of the ovum to the uterus via ciliary movement. 

So, the correct answer is 'Ciliary movement'.

The second maturation division of the mammalian ovum occurs

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. shortly after mutation before the ovum makes entry into the Fallopian tube

  2. Until after the ovum has been penetrated by a sperm

  3. Until the nucleus of the sperm has fused with that of the ovum

  4. In the Graafian follicle following the first maturation division

Show answer
Correct Option: B
Explanation:
During oogenesis, primary oocyte grows and completes meiosis I (first maturation division) producing a large secondary oocyte and a small polar body. The secondary oocyte proceeds with meiosis II (second maturation division) but the diyision gets arrested at metaphase stage. It is in this stage of oocyte that the ovum is shed during ovulation. It passes into oviduct, where the cell cycle resumes only after the entry of sperm.
So, the correct answer is 'Until after the ovum has been penetrated by a sperm'.

Level of follicle stimulating hormone (FSH) during infancy and adulthood is the same but spermatogenesis is seen only during adulthood. mRNA levels coding for FSH receptors are also found to be same in testis of both age groups. Which of the following investigations will clarify this paradox a little more?

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. Culture testcular cells and add to see testosterone production.

  2. Culture testicular cells and add testosterone to see comparative rise in FSH mRNA from both age groups.

  3. Culture testicular cells and FSH to see comparative rise in cAMP production by both age groups.

  4. Add both LH and FSH to testicular cells and evaluate cAMP production.

Show answer
Correct Option: A
Explanation:

In males, FSH and LH are secreted by hypothalamus. FSH stimulates Sertoli cells of the testes to secrete androgen binding protein (ABP) that concentrates testosterone in seminiferous tubules. LH stimulates interstitial cells (leydig's cells) of the testes to secrete androgens testosterone. Androgens stimulate germinal epithelium to undergo spermatogenesis.

Arrange the following stages of fertilisation and early development into a proper sequence.
I. Sperm entry
II. Acrosomal reaction
III. Karyogamy
IV. Capacitation
V. Cortical reaction

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. I, III, II, IV, V

  2. III, V, I, IV, II

  3. IV, II, V, I, III

  4. V, I, IV, II, III

Show answer
Correct Option: A
Explanation:
Fertilization can be described as the following steps:
1. Sperm Capacitation. 
2. Sperm-Zona Pellucida Binding. 
3. The Acrosome Reaction. 
4. Penetration of the Zona Pellucida. 
5. Sperm-Oocyte Binding.
6. Egg Activation and the Cortical Reaction. 
7. The Zona Reaction.
8. Post-fertilization Events.
So, the correct option is 'I, III, II, IV, V'.

Which of the following events occur in the part of human reproductive system? 

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. Fertilisation

  2. Implantation

  3. Both of them

  4. None of them

Show answer
Correct Option: C
Explanation:

  • Fertilization is the process of the fusion of the male and the female gamete. This process takes place in the ampullary region of the fallopian tube. 
  • The implantation is the process of attachment of the fetus to the wall of the uterus. Both of these events occur in the parts of the female reproductive system. 
Thus, the correct answer is option C. 

Zygote is formed by the process of

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. Anisogamy

  2. Isogamy

  3. Oogamy

  4. Syngamy

Show answer
Correct Option: D
Explanation:

The process of fusion between a haploid male nucleus and an egg nucleus is known as amphimixis. It is also known as syngamy or fertilization which leads to formation of a diploid zygote. It leads to the recombination of character which causes variation. It is a mode of sexual reproduction.

A single sperm fuses with the ova and releases its nuclei and cellular contents in the ovum. The condition when the multiple sperm fuses with a single ovum is known as polyspermy.
So, the correct answer is option D.

Fertilization is the fusion of sperm and ovum.

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Fertilization is the fusion of male and female gametes to initiate the development of a new individual by the formation of diploid cell i.e., the zygote.  In mammals including humans, fertilization is internal, takes place inside the human body.
Thus, the correct answer is option A.

Fertilization occurs in human, rabbit and other placental mammals in

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. Ovary

  2. Uterus

  3. Fallopian tubes

  4. Vagina

Show answer
Correct Option: C
Explanation:

In most mammals fertilization of the ovum takes place in the fallopian tubes. After fertilization initial process of cell division occurs in the fallopian tube that leads to the formation of the morula and blastula stage. After this Blastula enters the uterine cavity (the inside of the uterus).

When was the first test tube baby born?

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. 2 January 1981

  2. 25 July 1978

  3. 3 August 1975

  4. 4 February 1982

Show answer
Correct Option: B
Explanation:
World's First Test Tube Baby Born. On this day in 1978. Louise Joy Brown, the world's first baby to be conceived via in vitro fertilization (IVF) is born at Oldham and District General Hospital in Manchester, England, to parents Lesley and Peter Brown. So, the correct option is "B"25 July 1978.

Fertilization in humans is practically feasible only if

biology for the continuity of generation fertilization in human being fertilization in humans human fertilization

  1. the ovum and sperms are transported simultaneously to ampullary - isthmic junction of the fallopian tube

  2. the ovum and sperms are transported simultaneously to ampullary - isthmic junction of the cervix

  3. the sperms are transported into cervix within $48$ hours of release to ovum in uterus

  4. the sperms are transported into vagina just after the release of ovum in fallopian tube.

Show answer
Correct Option: A
Explanation:
Ampulla averages 5–8 cm in length. It is within this highly ciliated portion of the oviduct that fertilization and early embryo development occur. The ampulla is most often also the site for ectopic implantation (ectopic pregnancy). The next region, approximately 2–3 cm in length, is the isthmus. Like the ampulla, it too is ciliated yet less densely so. The isthmus is thought to regulate sperm and embryo transport.
So, the correct option is 'the ovum and sperms are transported 'simultaneously to ampullary - isthmic junction of the fallopian tube'