All Free Biology MCQs with Answers

• A. Sperm duct
• B. Scrotum
• C. Urethra
• D. Gamete

Explanation: The structure that transports sperm from the testes to the penis is the vas deferens.

• A. Pluripotent stem cells
• B. Blood stem cells
• C. Cord blood stem cells
• D. Both Options A and B are correct

Explanation: The correct answer is cord blood stem cells. The umbilical cord contains blood stem cells, specifically referred to as cord blood stem…

• A. Endometrium
• B. Perimetrium
• C. Corpus luteum
• D. None of these options are correct

Explanation: After the release of the egg (ovulation) from the ovarian follicle, the remaining structure transforms into a specialized endocrine organ…

• A. After about 7 days of fertilization
• B. After about two months of fertilization
• C. After about three weeks of fertilization
• D. After about 30 days of fertilization

Explanation: Once the embryo reaches the blastocyst stage, approximately five to six days after fertilization, it hatches out of its zona pellucida and…

• A. Gestation
• B. Fertilization
• C. Cleavage
• D. Implantation

Explanation: The order of events in pregnancy is as follows: Fertilization → Cleavage → Implantation Fertilization means the fusion of an egg and a…

• A. 7th
• B. 4th
• C. 5th
• D. 3rd

Explanation: At three months of gestation, the developing human organism is typically referred to as a fetus rather than an embryo.

• A. 7 months
• B. 5 months
• C. 12 months
• D. 10 months

Explanation: A full-term pregnancy typically lasts around 40 weeks, or about 9 months.

• A. Graafian follicle
• B. None of these
• C. Adrenal cortex
• D. Adrenal medulla

Explanation: In females, testosterone is primarily produced by the ovaries and the adrenal cortex.

• A. Embryo
• B. Fetus
• C. Zygote
• D. Infant

Explanation: At three months of gestation, the developing human organism is typically referred to as a fetus rather than an embryo.

• A. Cytokinin
• B. Giberellins
• C. Auxins
• D. All of these

Explanation: All of the listed hormones (cytokinin, auxins, and gibberellins) can promote parthenocarpy.

• A. 4
• B. 2
• C. 1
• D. 3

Explanation: In spermatogenesis, each meiotic division gives rise to four functional gametes.

• A. Ovary
• B. Uterus
• C. Cervix
• D. Fallopian tube

Explanation: The secondary oocyte completes its maturation in the fallopian tube. After ovulation, the secondary oocyte is released from the ovary and…

• A. Uterine wall is prepared for implantation of embryo
• B. Menstrual flow
• C. Levels of estrogen fall
• D. Ovulation

Explanation: The time duration of days 16-28 is known as the luteal phase. During this time, the uterine wall is prepared for the implantation of the…

• A. May be haploid or diploid
• B. Triploid
• C. Haploid
• D. Diploid

Explanation: The ovum (egg cell) formed after fertilization is diploid. Fertilization is the process by which a sperm cell, which is haploid, combines…

• A. Ovulation
• B. Implantation
• C. Fertilization
• D. None of these

Explanation: The oviduct, also known as the fallopian tube, is specialized for the transport of eggs (or ova) from the ovary to the uterus.

• A. 16-28
• B. 1-7
• C. 11-14
• D. None

Explanation: The most fertile period during the menstrual cycle is typically around the time of ovulation.

• A. Luteinizing hormone
• B. Follicle stimulating hormone
• C. Estrogen
• D. Oxytocin

Explanation: Estrogen, a hormone produced mainly by the ovaries, does influence the menstrual cycle and the endometrial lining in several ways.

• A. 5-13 days
• B. 1-4 days
• C. 14-20 days
• D. 20-28 days

Explanation: Following menstruation, the proliferative phase begins. It usually lasts from around day 6 to day 14 of a 28-day cycle, but the exact…

• A. From day 16-28
• B. From day 1-5
• C. At day 14
• D. From day 6-12

Explanation: Follicular Phase (Days 6-14): The early follicular phase overlaps with the menstrual phase.

• A. Seminal vesicles
• B. Scrotum
• C. Prostate gland
• D. epididymis

Explanation: Sperm is produced in the testes, specifically in structures called the seminiferous tubules.