Development of Male Reproductive System PDF

10/23/2024 Development of Male Reproductive System By Assistant Prof. Omar Abd-Alhakeem Ammar Assistant Professor of Cell Biology and Histology Director of Quality A...

10/23/2024 Development of Male Reproductive System By Assistant Prof. Omar Abd-Alhakeem Ammar Assistant Professor of Cell Biology and Histology Director of Quality Assurance Unit Intended Learning Outcomes (ILOs) Identify the structures and major organs of the male reproductive system and describe their functions. Trace the pathway of the sperm cells in the organ system. 1  10/23/2024 Reproduction ❑ Humans sexual reproduction and unisexual. ❑ Each sex has pair of gonads, reproductive duct and accessory structures. ❑ Sex organs: Testis (paired) male, ovaries (paired) Gamete formation, hormones. ❑ Puberty: sexual maturity (ability to reproduce) 2  10/23/2024 Reproduction ❑ It is the process by which our genetic material is passed on from one generation to the next generation. This maintains continuation of the species. It involves passing of genetic material from parent cells to daughter cells. ❑ This process requires the sperm from the male and the egg from the female. ❑ The fertilization is the process of union of a male sperm and female ovum to produce a fertilized egg, or zygote. ❑ When fertilization occurs, the zygote will possess 46 chromosomes (an ovum carrying 23 chromosomes and the sperm carrying 23). Reproductive System ❑ Defined: organs & glands that produce hormones which help make a new human. ❑ Hypothalamus & Pituitary glands release 2 major hormones: Develop sexual characteristics and reproductive system 1) FSH 2) LH 3  10/23/2024 What is the male reproductive system? Male Reproductive System: ❑ Consists of a number sex organs that are a part of the human reproductive process. ❑ Produces, stores and releases the male gametes, or sperm. * gametes- a sex cell Reproductive System ❑ Human reproduction and development are carried out by specialized organs. The function of these organs is regulated by hormones from the endocrine system. ❑ In humans, as in nearly all mammals, fertilization and development occur internally- within the mothers body. ❑ Reproductive organs in other mammals are similar in appearance and function. 4  10/23/2024 Males vs. Females Similarities: Differences: ▪ 2 compartments ▪ Male(XY) Testes Produce MILLIONS of sperm every day Ovaries ▪ Female (XX) ▪ Start inside body One egg, once a month Testicles drop before birth ▪ Fetus has glands that could become either female or male Father "determines" gender Depends on genes -XX: Female -XY: Male Male Reproductive System Function: ▪ Produce sperm ▪ Deliver sperm to female egg ❑ Testes: - Outside body If temp is too high, sperm can't be made - Produces Testosterone Develops male sex characteristics Makes sperm 5  10/23/2024 Male reproductive organs External Genital Organs Internal Genital Organs 1. Penis 1. Testis 2. Scrotum 2. Epididymis 3. Vas Deferens 4. Accessory Glands a. Seminal Vesicles b. Prostate Gland c. Bulbourethral Glands Penis ❑ The penis is the organ by which the sperm is introduced into the female. ❑ It contains spongy tissue that becomes turgid and erect when filled with blood. 6  10/23/2024 Scrotum ❑ A pouch of skin formed from the lower part of the abdominal wall. ❑ The scrotum keeps the testes at a temperature slightly cooler than body temperature. Testis ❑ The testes are the two-oval shaped male organs that produce sperm and hormone testosterone. ❑ Each testis is made of tightly coiled structures called seminiferous tubules. ❑ Among tubules are cells that produce testosterone. * Testosterone- the primary male sex hormone 7  10/23/2024 Testis seminiferous tubule – Sperm production lined on its inside by two types of cells: a) Male germ cells (spermatogonia) - meiotic divisions - sperm formation. b) Sertoli cells (supporting cells): provide nutrition to the germ cell. 8  10/23/2024 seminiferous tubule – Sperm production ❑ regions outside the seminiferous tubules called Interstitial spaces, contain small blood vessels & interstitial cells/ Leydig cells. ❑ Leydig cells: synthesise & secrete male hormone Androgen (testosterone). ❑ Other immunologically competent cells are also present. Epididymis ❑ The epididymis is a tightly coiled tubes against the testicles. ❑ It acts as maturation and storage place for sperm. ❑ The sperm that produced from the testes are immature and unable for fertilization; therefore the epididymis performs maturations of the sperm. During sexual stimulation, epididymis transports the sperm into the vas deferent duct. 9  10/23/2024 Vas Deferens (Ductus Deferens) ❑ The vas deferens is a thin tube that starts from the epididymis to the urethra in the penis. ❑ They transport sperm from the epididymis in ejaculation. Urethra ❑ The urethra is the tube that carries urine from the bladder to outside of the body. In males, it has the additional function of ejaculate semen. 10  10/23/2024 Accessory Ducts ❑ rete testis, vas efferentia, epididymis, vas deferens Accessory glands ❑ The accessory glands secrete the liquid portion of the semen. ❑ These glands produce nourishing fluids for the sperms that enter the urethra. a. Seminal Vesicles b. Prostate Gland c. Bulbourethral Glands 11  10/23/2024 Seminal Vesicles ❑ The Seminal Vesicles are sac-like structures attached to the vas deferens at one side of the bladder. ❑ They produce a sticky yellowish fluid that contains fructose that provides a source of energy for sperm motility. Prostate Gland ❑ The Prostate Gland surrounds the ejaculatory ducts at the base of the urethra, just below the bladder. ❑ The Prostate Gland is responsible for making the production of semen, a liquid mixture of sperm cells, prostate fluid and seminal fluid. ❑ Prostate fluids also help for nourishment of the sperms. 12  10/23/2024 Prostate Gland ❑ Function: Produces fluid that nourishes and protects sperm. ❑ Sperm + fluid = semen ❑ prostate Cancer: - Most common male cancer - Usually slow growing - Prostate exams help monitor - Treatment: Radiation, Chemotherapy, surgery Bulbourethral Glands (Cowper's gland) ❑ The Bulbourethral Glands are two small glands located on the sides of the urethra just below the prostate gland. ❑ These glands produce a clear, slippery fluid that empties directly into the urethra. ❑ This fluid serves to lubricate the urethra and to neutralize any acidity that may be present due to residual drops of urine in the urethra. 13  10/23/2024 Semen ❑ Semen is an alkaline milky sticky fluid containing mixture of sperm cells and the secretions of the seminal vesicles, the prostate, and the bulbourethral glands. ❑ The semen provide nutrients to the sperms in the male urethra and female vagina. It provides a transport medium for the swimming sperm. ❑ Typical ejaculate is 2.5 to 5 ml in volume ❑ Normal sperm count is 50 to 150 millions/mL Review: ❑ The main function of the Male Reproductive System is to produce sperm cells and deliver them to the female reproductive system. ❑ It consists of external and internal genital organs which are essential for the continuous reproduction of life. 14  10/23/2024 Question # The mitochondrion is located in which part of the sperm cell? a) Head b) Midpiece c) Tail d) Acrosome Question # The mitochondrion is located in which part of the sperm cell? b) Midpiece 15  10/23/2024 Question # In which organ of the human male does the mature sperm stored for a time? a) Testis b) Epididymis c) Vas Deferens d) Accessory Glands Question # In which organ of the human male does the mature sperm stored for a time? b) Epididymis 16 10/23/2024 17