Practical Report on human sexual reproduction.

BIOLOGY 2: PRACTICAL REPORT

HUMAN SEXUAL REPRODUCTION

Reproduction is the generation of new individuals of the same species. In asexual reproduction individuals are derived from one parent and no special reproductive structures are involved. The simplest form is fission, occurring mostly in unicellular organisms. Simple multicellular organisms, such as sponges and coelenterates, reproduce by budding where a new individual arises as an outgrowth (bud) from the parent. In fragmentation's, the individual breaks into two or more parts, each capable of growth to form a new individual; this is seen in flatworms and algae.

Most animals however reproduce by a process involving specialized reproductive cells called gametes. They fuse to produce a new individual with a different genetic makeup. This process is known as sexual reproduction. Sexual reproduction involves the fusion of two haploid gametes to form diploid zygote. The female gamete, oram (unfertilized egg) is a relatively large cell. The male gamete, the spermatozoa is generally a small flagellated cell.

English: Electron microscope image of sperm.

English: Diagram of a cross-section of the human m...

sperm

It occurs in its simplest form in conjugation. In more complex forms organisms the gametes are produced in special organs such as the carpel and stamen in flowering plants and the ovary and testes in animals. The importance of sexual reproduction in nature is that it allows genetic variation in a population, which is therefore better able to adapt to the changing environment.

Part A : IDENTIFYING THE ORGANS OF THE MALE AND FEMALE REPRODUCTIVE SYSTEMS

i)The male reproductive system

The process of Meiosis occurs in the organ called the testes.

The two testes are located in a loose pouch of skin three layers thick; this is because sperm production cannot occur at normal body temperature. The temperature in the scrotum is about 3 degrees below Celsius.

The epididymis serves to store, mature and transport spermatozoa between the testis and...