50 free Reproductive System trivia questions with answers — science & nature quiz, new questions added Aug 2026.
This reproductive system trivia quiz covers the human reproductive system the way a biology or health class would: the female organs from ovary to cervix, the male organs from testis to urethra, the glands that add fluid to semen, and the hormones that run the whole show, from GnRH and FSH to estrogen, progesterone and testosterone. It also digs into the cell biology and development: meiosis and the 23-chromosome gamete, how one oocyte yields a single ovum while a spermatocyte yields four sperm, the Wolffian and Müllerian ducts, the week the embryo's sex is set, when the testes descend, and the 28-day cycle with its follicular and luteal phases. The opening questions suit a middle or high school review; the later ones reward anyone who has taken anatomy and physiology. Every answer was checked against encyclopaedia entries before publishing.
30 of 50 questions with answers and explanations. Play the quiz
Q 01Which paired organs produce the egg cells and secrete the main female hormones?
Ovaries
They sit on either side of the uterus and work as endocrine glands as well as gamete factories.
Q 02What is the lining of the uterus called?
Endometrium
It thickens each cycle to receive an embryo and is shed during menstruation if none implants.
Q 03Fertilisation of the ovum usually happens inside which structure?
The fallopian tube
The fertilised egg then travels on to the uterus and implants in its lining.
Q 04What is the narrow neck of the uterus, where it joins the vagina, called?
Cervix
It dilates during labour to let the infant pass from the uterus into the birth canal.
Q 05What is a fertilised ovum called?
Zygote
Only one sperm is needed to fertilise the egg and create it.
Q 06What is the release of an egg cell from the ovary called?
Ovulation
It usually happens in just one of the two gonads each cycle.
Q 07What is the median length of the menstrual cycle, in days?
28
Normal cycles run anywhere from 21 to 35 days.
Q 08Menarche, the first period, usually occurs around what age?
12
Cycles then continue for roughly 30 to 45 years until menopause.
Q 09Which hormone stimulates the uterus lining to thicken each cycle?
Estrogen
The thickened lining's blood supply feeds an embryo if one implants.
Q 10Menstruation is triggered by falling levels of which hormone?
Progesterone
The shed lining is a sign that pregnancy has not occurred.
Q 11The hypothalamus controls the cycle by releasing which hormone?
GnRH
It prompts the nearby anterior pituitary to release FSH and LH.
Q 12What does FSH stand for?
Follicle-stimulating hormone
Its cyclical rise and fall prompts the growth of oocytes.
Q 13A surge of what from the pituitary triggers release of the mature oocyte?
Luteinizing hormone
The same hormone regulates testosterone release in males.
Q 14How many chromosomes does a human gamete carry?
Q 21Which interstitial cells of the testes produce testosterone?
Leydig
Their androgens drive puberty, facial hair, sexual behaviour and libido.
Q 22Which supporting cells of the sperm-producing tubules secrete the hormone inhibin?
Sertoli
Inhibin dampens FSH release from the pituitary, helping regulate sperm production.
Q 23The scrotum keeps the testes roughly how many degrees Celsius below core body temperature?
3
Sperm production and survival need that slightly cooler environment.
Q 24Which tube, also called the sperm duct, carries sperm toward the ejaculatory duct?
23
Two gametes fuse to restore the diploid count of 46.
Q 15Which type of cell division halves the chromosome number to make gametes?
Meiosis
It turns diploid germ cells into haploid ones.
Q 16Gamete production within the gonads is known as what?
Gametogenesis
In males it is called spermatogenesis and in females oogenesis.
Q 17Each primary oocyte ultimately forms how many mature ova?
One
The rest of the division products become polar bodies that cannot be fertilised.
Q 18Each primary spermatocyte forms how many functional gametes?
Four
That is the key contrast with oogenesis, which yields a single egg per germ cell.
Q 19In which structure do immature sperm gain their tails and the ability to move?
Epididymis
Sperm also mature and are concentrated there before moving into the sperm duct.
Q 20Sperm are produced in which fine coiled tubes inside the testes?
Seminiferous tubules
Germ cells lining them develop into sperm from puberty through old age.
Vas deferens
It is about 30 centimetres long and runs from the epididymis into the pelvic cavity.
Q 25Which gland below the bladder produces seminal fluid and helps regulate urine flow?
Prostate
It develops from the urogenital sinus in the embryo.
Q 26Which two glands behind the bladder secrete many of the components of semen?
Seminal vesicles
They form from lateral outgrowths of the mesonephric ducts.
Q 27The bulbourethral glands are also known by what other name?
Cowper's
They add fluid to semen during ejaculation.
Q 28A sperm carrying which chromosome results in a male child?
Y
The egg always carries an X, so it is the sperm that decides the sex.
Q 29Which enzyme converts testosterone into DHT inside target cells?
5α-reductase
DHT, not testosterone itself, mediates the androgen effect in the developing external genitalia.
Q 30Which embryonic structure forms the fallopian tubes, uterus and vagina?
Müllerian duct
It essentially disappears in the male embryo.