Biology Multiple Choice Questions on “Human Reproduction – Fertilisation”.
1. The population of vagina with semen during coitus is called as _______
a) Insemination
b) Outsemination
c) Copulation
d) Fertilization
Answer: a
Clarification: Coitus or copulation is the process that leads to the release of semen from the penis into the vagina. The sperms populate the vagina along with other contents of semen. This process is called insemination.
2. What is the correct order of travel of sperm through the female reproductive tract before it reaches the egg?
a) Vagina -> Fallopian tube -> Uterus -> Cervix
b) Vagina -> Cervix -> Uterus -> Oviduct
c) Vagina -> Uterus -> Cervix -> Oviduct
d) Vagina -> Fallopian tube -> Cervix -> Uterus
Answer: b
Clarification: Sperms are released into the vagina. From here, they travel through the cervix and uterus before reaching oviduct or fallopian tube, where they can encounter an egg.
3. The number of semen delivered by a male determines the number of babies the female can conceive.
a) True
b) False
Answer: b
Clarification: Males usually release millions of sperm at each coitus. However, the female tract prevents most of them from reaching the fallopian tube with only one sperm being able to fertilize the egg. However, in rare cases where female releases two eggs (one from each ovary), there’s a probability of conceiving twins. Thus it is the number of eggs and not the number of sperm that determines the number of babies that the female can conceive.
4. What part of the oviduct does the sperm encounter the egg?
a) Ampulla
b) Isthmus
c) Infundibulum
d) Fundus
Answer: a
Clarification: The egg is released and awaits in ampulla for the sperm. The sperms cross the reproductive tract barriers before reaching the ampulla to fertilize the egg.
5. During a menstrual cycle, copulation on which of the following phases has the least probability of fertilizing an egg?
a) Menstrual phase
b) Onset of follicular phase
c) End of the follicular phase
d) End of the luteal phase
Answer: c
Clarification: Fertilization occurs only when the egg and sperm are present in the ampulla at the same time. Hence the coitus should happen near the period of ovulation. Ovulation occurs at the end of the follicular phase or the onset of luteal phase.
6. What is fertilization?
a) Release of egg from ovary
b) Release of sperm from testis
c) Mixing of semen with vaginal fluid
d) Fusion of sperm with egg nuclei
Answer: d
Clarification: Ovulation is the release of egg from the ovary. Spermiation is the release of sperm from testis. Insemination is the release of semen into vagina. Fertilization is the process that leads to fusion of male and female gametes.
7. What layer of egg cell prevents entry of other sperms?
a) Corpus luteum
b) Zona pellucida
c) Endometrium
d) Corona radiata
Answer: b
Clarification: The sperm contacts the egg cell at zona pellucida. The zona pellucida then undergoes chemical changes which renders egg insusceptible to further encounters with another sperm. This is essential to ensure that only a single sperm fertilizes the egg.
8. What triggers the completion of meiosis of secondary oocyte?
a) Maturation of Graafian follicle
b) Entry of sperm into the egg cell
c) Release of estrogen
d) Coitus