Biology [1 Mark Question Answer]

They are located on the sides of the vaginal orifice in females.

They are located beneath the urinary bladder and behind the middle part of urethra about 4-5 cm below the prostate gland.

Ovaries are located in the upper pelvic cavity one on each side of the uterus.

It is present at the base of the urinary bladder surrounding the urethra.

They are located at the posterior end of vas deferens between urinary bladder and rectum in males.

It is located above and behind the urinary bladder in the abdominal cavity.

Its main function is the exchange of materials between mother and the fetus (such as nutrients, respiratory gases, and waste products).

The main function of the testis is the formation of spermatozoa.

Its main function is the formation of an ovum (oogenesis).

Their secretion provides an energy source for the sperms and neutralizes the acidic medium in the urethra and female tract.

These are paired tubes on either side of the uterus. They have a ciliated epithelial cell that carries the mature ovum to the uterus by the sweeping action of their cilia.

These are found in the testes. They are lined with germinal epithelium, the cells of which produce spermatozoa by spermatogenesis.

It secretes alkaline fluid into the semen. This fluid neutralizes the acidity of urine in the urinogenital canal.

It is one of the extra-embryonic membranes that protect the fetus and secretes a shock-absorbing fluid—amniotic fluid.

Its main function is to allow the oocyte to grow to full maturity and release of a mature ovum.

It acts as a common passage for urine and spermatic fluid (semen).

It connects the scrotum with the abdominal cavity.

It provides nutrition to the spermatozoa and neutralizes the acidic environment of the reproductive passage.

Its secretion lubricates the end of the penis during copulation and neutralizes the acidic environment of the urethra.

It is a pear-shaped muscular sac that holds, protects, and nourishes the fetus by its placenta.

In a boy: Change of voice and discharge of semen.
In a girl: Appearance of the menses, the appearance of mammary glands, and widening of the hips.

The union of male and female gametes to form the zygote is called fertilization. In human females the site of fertilization is an oviduct or fallopian tube.

Semen is the mixture of sperms and secretions from seminal vesicles, prostate gland and Cowper's (bulbo -urethral gland).

The main function of testes is the production or formation of sperms. They also secrete male sex hormone testosterone which is responsible for the development of secondary sexual characters in males.

Male reproductive organs of man:
1. A pair of testes.
2. A pair of the epididymis
3. A pair of the vas deferens
4. A pair of seminal vesicle
5. Urethra
6. Penis
7. Male reproductive glands (Cowper’s and Prostate gland).

Identical Twins (Produced from one egg): Sometimes a single fertilized egg may get split and separated into two parts during its early stages of cell division. Each of these two split parts then behaves like an independent egg and produces one complete individual each. These are called Identical twins.
Fraternal Twins: Sometimes, two eggs are released from ovaries at a time and both may get fertilized to produce two individuals. These are called fraternal twins.

(i) It has the longest reproductive phase.
(ii) There is no specific breeding season. It can take place at any time during the year.

The mammalian embryo respires by the diffusion of oxygen through the placenta to enter the bloodstream of the embryo. The waste carbon dioxide passes through the umbilical cord and leaves through the placenta.

It is formed by the union of uterine endometrial tissue, chorion, and allantois (embryonic tissue). It is attached to the wall of the uterus and through it, the exchange of nutrients, hormones, respiratory gases, and urea occurs between the fetal and maternal circulation.

The placenta is an organ composed of blood capillaries, villi, connecting tissue, and latent endocrinal cells.

1. Oestrogen produced by ovarian follicle and placenta.
2. Progesterone produced by corpus luteum.
3. Relaxin produced by ovary and placenta.

After fertilization, the zygote divides to form several celled embryo which is implanted in the uterus for further development.

The egg and sperm fuse to form zygote during fertilization.

The prostate gland secretes an alkaline secretion for the maintenance of the sperms while Cowper’s gland secretion is meant for lubrication.

Menstrual gland phase, follicular phase, ovulatory phase, luteal phase.

It is a type of reproduction usually found in higher animals and plants where male and female sexes produce male and female heterogametes separately, which on fertilisation produce a zygote.

Prostate gland

Scrotum

Testes

Epididymis

Spermatozoa

Penis

Seminiferous tubule

IUD: Intra-uterine device.

FSH: Follicle-stimulating hormone.

LH: Luteinizing hormone.

Tubectomy

280 days

Parturition

Oxytocin