1. Course Teacher: Imon Rahman

2. Introduction The reproductive functions of the male can be divided into three major subdivisions: 1. Spermatogenesis (Formation of sperm) 2. Performance of the male sexual act and; 3. Regulation of male reproductive functions by the various hormones.

3. Physiologic Anatomy of the Male Sexual Organ: Testis is the main sexual organ of male It is composed of up to 900 coiled seminiferous tubules, each averaging more than one half meter long, in which sperm are formed. Sperm then empty into the epididymis, another coiled tube about 6 meters long. The epididymis leads into the vas deferens which enlarges into the ampulla of vas deferens immediately before the vas enters the body of the prostate gland.

4. Physiologic Anatomy of the Male Sexual Organ (Continued): Two seminal vesicles, located on each side of the prostate, empty into the prostatic end of the ampulla. The contents from both the ampulla and the seminal vesicles pass into an ejaculatory duct leading through the body of prostate gland and then emptying into the internal urethra. Finally, the urethra is the last connecting link from the testis to the exterior.

5. Physiologic Anatomy of the Male Sexual Organ (Continued) : Fig: Male Reproductive systemFig: Internal Structure of Testis and relation of the testis to epididymis.

6. Spermatogenesis 1. Spermatogenesis, which means the formation of sperm. 2. During the formation of embryo, the primordial germ cells migrate into the testes and become immature germ cells called spermatogonia 3. Which lie in the two or three layers of the inner surface of the seminiferous tubules 4. Beginning of pubarty, spermatogonia undergo mitotic division,and development of sperm occors through continuos proliferation and differentiation.

7. Steps of Spermatogenesis Spermatogenesis occurs in the seminiferous tubules during active sexual life as the result of stimulation by Anterior pituitary gonadotropic hormones beginning at an average age of 13 years and continuing through most of the remainder of life, but decreasing markedly in old age. The steps includes- 1. Meiosis 2. Sex Chromosomes 3. Formation of sperm

8. Spermatogenesis (continued) Fig: Cell Division during Spermatogenesis

9. Formation of Sperm When the spermatids are first formed, they have the characteristics of epitheloid cells, but soon elongate into spermatozoa through differentiation. Each spermatozoon is composed of a head and a tail. The head comprises the condensed nucleus with a thin cytoplasmic and cell membrane layer On the anterior two thirds of the head is a thick cap called ‘Acrosome’

10. Formation of Sperm( Continued) Acrosome is formed mainly from golgi apparatus. This contains a number of enzymes similar to those found in lysosomes of the typical cell. Fig: Structure of Human Spermatozoon

11. What is Acrosome? What are theFunction of Acrosome? Function: 1. Enzymes contains hyaluronidase, which can digest proteoglycan filaments of tissue 2. It also contains powerful proteolytic enzymes which can digest proteins. 3. These enzymes play an important role in allowing the sperm to enter the ovum and fertilize it.

12. Formation of Sperm( Continued) The tail of the sperm, called the flagellum, has three major components: 1. a central skeleton constructed of 11 microtubules, collectively called the axoneme— the structure of this is similar to that of cilia found on the surfaces of other types of cells. 2. a thin cell membrane covering the axoneme; and 3. a collection of mitochondria surrounding the axoneme in the proximal portion of the tail (called the body of the tail).

13. Hormonal Factors that stimulate Spermatogenesis 1. Testosterone, Secreted by the Leydig cells essential for the growth and devision of the testicular germinal cells 2. Leutinizing hormone (LH), secreted by the Anterior pituitary gland. 3. Follicle stimulating Hormone (FSH), secreted by Anterior Pituitary Gland 4. Estrogens 5. Growth hormone necessary for controlling metabolic function of the testis.

14. Function of Seminal Vesicle Seminal vesicle is mainly tortuous organ. They secrets mucoid substance, which is mainly mucuous substance composed of Fructose, Citric acid and other nutrients. Prostaglandin and fibrinogen is also present. Function of these substances: 1. Increse bulk volume of semen 2. Prostaglandin helps in fertilization in two ways- By reacting with female cervical mucous to make it more receptive to sperm movement By causing backward and reverse peristaltic movement in the uterus and fallopian tube.

15. Function of Prostate Gland Prostate gland secretion is mainly thin and milky fluid, that contains- calcium, citrate ion, phosphate ion, a clotting enzyme and a profibrinolysin. The pH of this secretion is slightly alkaline to neutralize the acidic environment of vagina ( pH 3.5- 4 ), also neutralizes the vas deferense fluid which is also acidic.

16. Function of Testosterone 1. Effect of testosterone to cause descent of the testis 2. Effect on development of adult primary and secondary sexual characteristics. 3. It increases thickness of the skin and can contribute to the development of acne 4. It increases protein formation and uscle development 5. It increases bone matrix and causes calcium retention 6. It increases basal metabolism 7. Effect on red blood cells 8. Effect on electrolyte and water balance.

17. Secondary Sexual characteristics of Male External genetalia: penis increases in length and width and scrotum become pigmented. Internal genetalia: Seminal vesicle enlarge and secrete and began to form fructose. Voice: Become more harsh, larynx are enlarged and vocal cord increases in length. Hair growth: beard and mostache, hair appered on chest. Mental Change : become more aggressive. Active attitude and interest to have sex. Body conformation: shoulder become broaden, muscle enlarge.

18. Characteristics of Semen White, opalescent pH 7.35- 7.5 2-4 ml/ ejaculation Sperm count 100 million/ml Composition: Fructose Ascorbic acid Prostaglandin flavin

19. Sterility It can be defined as a condition of being unable to conceive or reproduce the species. Means, loss of reproductive capacity. Causes: Failure of erection of penis Less sperm found(below 60 million per ejaculation) Presence of more than 20 % abnormal sperm Impair movement of the sperm due to acidic pH, malnutritionor genetic infection Presence of antibodies that identify sperm as harmful invaders

20. Impotency Defines as an inability to perform the sexual intercourse or failure of erection of penis Causes: 1. In men over the age of 60, the leading cause is atherosclerosis that restrict the flow of blood to the penis 2. Injury or disease of the connective tissue 3. Malnutrition 4. Excessive utilization, mental unability, genetic infection