Human Reproduction

Human Reproduction:

• Human reproduction is any form of sexual reproduction resulting in human fertilization.
• The reproductive system is a system of organs that takes part in this process.
• Humans are sexually reproducing and viviparous.
• The rate of reproduction is slower in sexual reproduction.
• Humans are unisexual.
• The reproductive events in humans include the formation of gametes (gametogenesis), i.e., sperms in males and ovum in females, transfer of sperms into the female genital tract (insemination), and fusion of male and female gametes (fertilization) leading to the formation of zygote.
• This is followed by the formation and development of blastocyst and its attachment to the uterine wall (implantation), embryonic development (gestation), and delivery of the baby (parturition).
• The beginning of sexual maturity or the ability to reproduce is known as puberty. Puberty occurs at the age of 10 - 14 years in girls and 13 - 15 years in boys.
• There are remarkable differences between the reproductive events in the male and in the female, for example, sperm formation continues even in old men, but the formation of ovum ceases in women around the age of fifty years.
• The reproductive system of each sex consists of many organs. The latter is distinguishable into primary and secondary sex organs. Besides these, there are some accessory sex characters.

1. Primary sex organs: Primary sex organs are also called gonads which form gametes like - testis in males and ovary in females. Testis produces sperms and secretes testosterone. The ovary produces ova and secretes estrogen. The male gamete is a spermatozoon. The female gamete is the ovum.
2. Secondary sex organs: Sex organs, glands, and ducts which do not produce gametes but are otherwise essential for sexual reproduction are known as secondary sex organs. In males, these include the epididymis, vas deferens, seminal vesicles, prostate, bulbourethral glands, penis, etc. In females, these organs are the fallopian tube, uterus, vagina, Bartholin gland, etc.
3. Accessory / External / Secondary sex characters: These are traits which do not have any direct role in reproduction but provide specific features and structures to both sexes.