Sexual Intercourse in Human Reproduction

As per nature, it has been observed that all living things including, humans, animals, and plants reproduce offspring of their own kind. Few lay their egg, few reproduce by parturition to their young ones and few living things like plants reproduce by producing seeds.

Reproduction is the fundamental organic process of manufacturing individuals of an equivalent kind of species. This process makes sure that there is a continuity of species, generation after generation. Sexual reproduction and Asexual reproduction are the 2 types of reproduction that any animal or human being goes through. In this mode of reproduction, there's an involvement of two parents and therefore the offspring features a fusion of the characteristics of both the oldsters. 

Sexual Reproduction: Male and Female Reproductive Organs

Sexual reproduction may be a general and primarily important mode of reproducing their young ones in animals, humans, and plants. Compared to agamogenesis, amphimixis is lengthy and more complex. An organism that follows amphimixis has precise reproductive organs. The reproductive organs of both male and females differ from each other. 

Male Reproductive organs

The male reproductive organs are located within the lower abdomen around the pelvic region. The basic reproductive function of the male reproductive organ is to deliver sperm so that fertilization can take place. The male reproductive system is mainly composed of: 

• Scrotum– a little muscular sac-like organ that is found below and behind the penis. It consists of the testes and is especially involved in maintaining the temperature required for sperm production.

• Testes – It is also called testicles. They are a pair of oval-shaped organs that are mainly liable for the sperm production and synthesis of testosterone- male hormones.

• Penis– it's the first sexual organ which is both a sex organ as well as a urinary organ and used for the aim of sexual activity. The shape of the penis is cylindrical tube-like which has a small opening at the top and is extremely sensitive. It takes a vertical turn when a person is sexually aroused and ready for sex. The semen that contain sperm, ejaculate sperm from the opening at the top when the person reaches sexual climax.

• Urethra– A narrow tube-like structure that conducts urine and semen from the bladder to the penis.

• Vas Deferens– it's a muscular tube that carries mature sperm produced within the testes to the urethra.

Female Reproductive organs

The female reproductive organs are located near the lateral walls of the cavity which consists of the subsequent major organs:

• Ovaries– These are a pair of organs that are solely responsible for the production and storage of ovum, or egg, which are the sex gametes in a female.

• Uterus– It is also defined as the womb where a baby stays.  It is a pear-shaped muscular bag-like organ with a robust muscular lining that holds the baby after fertilization. The uterus is referred to as the place where the embryo develops as it protects the fertilized ovum and holds it till the baby is mature enough for birth.

• Cervix– A cylinder ring-shaped tissue which consists mainly of fibromuscular tissue. It is located at the lower portion of the uterus and is involved in connecting the uterus and the vagina.

• Vagina– It is the sexual organ that serves as both an excretory organ as well as a reproductive organ. It is a muscular and tubular part of the feminine genital tract that opens outside the body and therefore the opening of the vagina is named the vulva, which also includes the clitoris, labia, and urethra. The vagina connects the cervix to the external human body parts and it's the trail for penis during coitus also as a fetus during delivery.

Fertilization

Fertilization is the fusion of haploid gametes- sperm with egg to supply the diploid zygote. It is the crucial stage of reproduction as, without fertilization, amphimixis is futile. This process is of two types: 

1. Internal Fertilization:

In internal fertilization, the fusion of sperm and egg takes place within the feminine parent. In this process, the sperms are released into the body of the females during copulation and therefore the resulting zygote develops internally within the mother and gets its nourishment from her. This type of fertilization is found altogether in humans, and most animals like cats, dogs, cows, lions, etc.

2. External Fertilization:

In external fertilization, the fusion of sperm and egg is carried outside the feminine parent. This type of fertilization is found in a very less number of organisms. In this process, the feminine parent lays her eggs and later, these eggs are fused by the father by ejecting his sperms over the eggs.

Development of Embryo

After the method of fertilization, the formed diploid zygote divides mitotically and develops into an embryo. This process is defined as the embryogenesis in which the cell differentiates and modifies accordingly. Embryogenesis is administered in the first eight weeks of development and at the start of the ninth week, the embryo is called a fetus.

Viviparous and Oviparous Organisms

Animals are classified into oviparous and viviparous supporting the zygote development .i.e. internal fertilization and external fertilization.

In oviparous organisms, the fusion of sperm and egg takes place outside the feminine parent by laying eggs. Oviparous consists of Birds, reptiles, and egg-laying mammals. In all viviparous organisms, the fusion of sperm and egg takes place within the feminine parent and provides birth to young ones.