Fundamentals of Entomology

Male reproductive system

• The main functions of the male reproductive system are the production and storage of spermatozoa and their transport in a viable state to the reproductive tract of the female. Morphologically, the male tract consists of paired testes, each containing a series of testicular tubes or follicles (in which spermatozoa are produced) which open separately into the sperm duct or vas deferens. This vas deferens expands posteriorly to form a sperm storage organ or seminal vesicle.
• Tubular paired accessory glands are formed as diverticula of the vasa deferentia. Some times the vasa deferentia themselves are glandular and fulfil the functions of accessory glands. The paired vasa deferentia unite where they lead into ejaculatory duct (the tube that transports the semen or the sperm to the gonopore). Accessory glands are 1-3 pairs associated with vasa deferentia or ejaculatory duct. Its function is to produce seminal fluid and spermatophores (sperm containing capsule).

Physiology of reproduction
 

Spermatogenesis (occurs inside sperm tube)	Oogenesis (occurs inside egg tube)
Spermatogonia	Oogonia
Mitosis	Mitosis
Primary Spermatocytes (2n)	Primary oocytes (2n)
Meiosis	Meiosis
Secondary Spermatocytes (n)	Secondary oocytes (n)
Mitosis	Mitosis
Spermatids (n)	Oocytes (n)
Spermiogenesis	Vitellogenesis
Sperms (n)	Ovum (n)

3. Sperm transfer
(i) Intragenital: Common method, through, aedeagus via vaginal orifice into female genital passage.
(ii) Haemocoelous : Sperms transfered into the body cavity e.g. Bed bug.
(iii) External: Spermatophores are ejected out into open place by male while female walk over it and gets inseminated e.g. Silver fish.
4. Fertilization: Sperm enter into egg to produce morphogenesis. Egg nucleus divides meiotically into female gamete nucleus and polar body. Then the fertilization occurs by the fusion of male and female gamete nuclei.