Human Reproductive System
Reproduction is a fundamental and biological process by which an organism produces its own kind or its offspring. Reproduction ensures the continuity of life on earth.
The reproductive system is a system of organs within an organism which work together for the purpose of reproduction. There are two forms of reproduction-
- Asexual reproduction
- Sexual reproduction
When a single organism reproduces without the involvement of another organism, it is known as asexual reproduction. Some of the kinds of asexual reproduction are fission where a unicellular organism divides into two or more cells, budding in Hydra, fragmentation in spirogyra, and vegetative propagation in plants among others.
However, we are going to concentrate on reproduction in a complex multicellular organism – Human Beings. Our body consists of trillions of cells and hence, reproducing a new individual will be much more complicated than asexual reproduction. The reproduction of human beings is a type of sexual reproduction.
Sexual reproduction occurs in both plants and animals. Sexual reproduction is achieved through the combination of reproductive cells from two individuals. Each parent – a male and a female, contributes its genetic material, giving rise to an offspring having qualities from both.We are now going to study about the human reproductive system.
The human reproductive system specializes in –
- The production of reproductive cells in males and females.
- The interaction between the two cells.
- The nurturing of the fused cell or the embryo.
These functions are well-distributed between the female and male reproductive systems. The reproductive systems in males and females differ from each other significantly. The organs involved in the process of reproduction in both are different and so are their functions. The male reproductive system produces the reproductive cells (sperms) and deposits them. The female reproductive system produces the reproductive cells (ova or eggs), and protects and nourishes the fetus inside the female body.
1. FEMALE REPRODUCTIVE SYSTEM
In humans, the female reproductive system is immature at birth and develops to maturity at puberty. The reproductive system also releases hormones required for the development of secondary sexual characteristics in a female during this time, like growth of body hair, widening of hips, development of breasts etc. The female reproductive system mainly consists of a pair of ovaries, a pair of fallopian tubes, uterus, cervix, and vagina. Each organ has a specific function.
They produce the female reproductive cell called egg or ovum (plural ova). They periodically release eggs into the fallopian tubes by a process called ovulation. They also secrete hormones like estrogen and progesterone that play roles in the menstrual cycle and fertility.
b) Fallopian tubes:
These are narrow tubes that connect the ovaries to the uterus. The egg travels down through one of the fallopian tubes after ovulation. The sperms travel up to the fallopian tubes after contact. The fusing of the male and the female reproductive cells known as fertilization takes place in the fallopian tubes. Fertilization results in the formation of a fused cell called a zygote. The zygote produces the embryo.
The uterus is a muscular organ that nourishes and houses the developing embryo. It is also called the womb. This is where the embryo develops into a fetus.
It is the lower narrow part of the uterus that forms a canal between the uterus and vagina.
It is the passageway leading from the uterus to the outside of the female body. It is also called as the birth canal. The developing fetus comes out through this opening. Aside from its function in reproduction, it also plays a role in menstrual cycles, wherein blood from the uterus is released through the vagina.
2. MALE REPRODUCTIVE SYSTEM
The reproductive system releases hormones required for the development of secondary sexual characteristics during puberty in males. This includes the growth of body and facial hair, heavier body, and bone structure, deepening of voice, etc. It is also responsible for the production of male reproductive cells known as sperms. The main organs of the male reproductive system are penis, scrotum, testes, and prostate gland.
a) Testicles (testes):
They are homologous to the female ovaries. These are male sex glands that produce the male reproductive cells called sperms. Males have two testicles of similar size. They also produce the hormone testosterone for the development of secondary sexual characteristics in boys.
These are sacs that hold the testicles. They protect the testes by maintaining the temperature at 35 degrees Celsius, which is ideal for the production of sperms. This is 2 or 3 degrees lower than the body temperature of 37 degrees Celsius.
The penis is a male organ used for the purpose of urination and sexual reproduction. Sperms float in an organic fluid called semen that is expelled into the female vagina through the penis during contact. This process is called ejaculation.
d) Prostate Gland:
It is a gland responsible for the production of semen. The muscles of prostate gland aid in the discharge or ejaculation of semen.
Human fertilization is the union of the ovum and the sperm. Once the sperms enter the female body, they travel up to the fallopian tubes and fertilize the ovum to produce a zygote. The zygote produces the embryo that eventually develops into a fetus inside the uterus. It takes around 9 months for the complete development of the fetus. The fully-grown fetus then makes its way through the birth canal into the outside world.
Voila! There comes out a new born baby!
Sperms approaching an egg
Fill in the blanks:
- Fission, Budding and Vegetative propagation are types of _______________.
- The male reproductive cells are known as ___________.
- The testes are responsible for secreting the hormone ____________.
- The ovaries produce female reproductive cells known as _________.
- The union of the male and female reproductive cells is known as ____________.
- Asexual Reproduction. Genetic material, also known as DNA