Human Male & Female Reproductive System

Presented by Mrs. Farkhunda Naz DA Degree College Phase VI Biology Deptt Human Male & Female Reproductive System

Female V/S Male

Contents of Presentation • What is Reproduction • Types of reproduction • Significance of sexual reproduction • Human Male reproductive system • Spermatogenesis • Human Female reproductive system • Oogenesis • Sexually transmitted diseases

What is Reproduction? • Reproduction is the biological process by which new individual organisms are produced. Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. • It is the process by which new organisms are generated. It is the mechanism of species continuation.

Types of Reproduction

Significance of sexual reproduction • Sexual reproduction is more common in unstable or unfavorable circumstances. • To create variations in species. As no two individuals are same, so genetic characters from both parents will help make a slightly different copy of themselves. These small variations accumulate over hundreds of years resulting in formation of new species. • New species facilitate evolution of organisms.

Human Male reproductive system • A pair of testes • Epididymis • Vas deference • Urethra • Penis Three types of accessory glands Seminal vesicles Prostate gland 3. Cowper’s gland

Testes enclosed in scrotum • Testes (testicles): produce sperm and androgens (male sex hormones). The most common androgen is called “testosterone”. Androgens cause males to develop male characteristics at puberty. • Scrotum: a pouch like structure that hangs behind the penis. It holds and protects the testes. It also contains numerous nerves and blood vessels.

Production of sperms in testes • The testes consist of a mass of coiled tubes (the seminiferous or sperm producing tubules) in which the sperm are formed by meiosis. Cells lying between the seminiferous tubules produce the male sex hormone testosterone. • When the sperm are mature they accumulate in the collecting ducts and then pass to the epididymisbefore moving to the sperm duct or vas deferens. The two sperm ducts join the urethra just below the bladder, which passes through the penis and transports both sperm and urine.

The Penis • The penis consists of connective tissue with numerous small blood spaces in it. These fill with blood during sexual excitement causing erection.

Accessory Glands • Three different glands may be involved in producing the secretions in which sperm are suspended. • Seminal vesicles . When present they produce secretions that make up much of the volume of the semen, and transport and provide nutrients for the sperm. • The prostate gland. It produces an alkaline secretion that neutralizes the acidity of the male urethra and female vagina.

Accessory Glands • Cowper’s glands have various functions in different species. The secretions may lubricate, flush out urine or form a gelatinous plug that traps the semen in the female reproductive system after copulation and prevents other males of the same species fertilizing an already mated female.

Spermatogenesis

Structure of a Sperm

Structure of SPERM • Sperm are made up of three parts: a head consisting mainly of the nucleus, a midpiece containing many mitochondria to provide the energy and a tail that provides propulsion

Human Female reproductive system • A pair of ovaries • Fallopian funnel • Uterus • Cervix • Vagina

Structure of Ovaries • The ovaries are a pair of oval or almond-shaped glands which lie on either side of the uterus and just below the opening to the fallopian tubes. In addition to producing eggs or "ova," the ovaries produce female sex hormones called estrogen and progesterone. The female, unlike the male, does not manufacture the sex cells. A girl baby is born with about 60,000 of these cells, which are contained in sac-like depressions in the ovaries.

Fallopian tubes • The fallopian tube extends from the uterus to the ovary. This tube carries eggs and sperm and is where fertilization of the egg, or "ovum" takes place. The fallopian tubes lie in the pelvic portion of the abdominal cavity and each tube reaches from an ovary to become the upper part of the uterus. This funnel-shaped tube is about three inches in length. The larger end of the funnel is divided into feathery, finger-like projections which lie close to the ovary. These beating projections, along with muscle contractions, force the ovum down the funnel's small end, which opens into the uterus.

The Uterus • The uterus is a hollow, pear-shaped organ that is the home to a developing fetus. • The uterus is divided into two parts: the cervix, which is the lower part that opens into the vagina, and the main body of the uterus, called the corpus. The corpus can easily expand to hold a baby. A channel through the cervix allows sperm to enter and menstrual blood to exit.

Cervix • The lower one-third of the uterus is the tubular "cervix," which extends downward into the upper portion of the vagina. • The cervix surrounds the opening called the "cervical orifice," through which the uterus communicates with the vagina.

The Vagina • The vagina is a muscular passage which forms a part of the female sex organs and which connects the neck of the uterus (called the "cervix") with the external genitals. • The vagina has three functions: as a receptacle for the penis during love-making; as a outlet for blood during menstruation; and as a passageway for the baby to pass through at birth.

Oogenesis

Sexually transmitted diseases • Gonorrhea • Syphilis • Genital herpes • AIDS

Quiz paper • 1: The function of urethra in male reproductive system is________ • Storage of sperms • Sperm formation • Ejaculation • Passage for urine and sperm • Q2: The most common androgen which is produced by testes is testosterone. • True • False • Q3: The ovaries produce female sex hormones ____and_______ • Q4: How uterus is helpful in development of embryo? • Q5: Three functions of vagina are____,_____ and____

References • Internet • Text book • www.Google.com • www.Youtube.com

Human Male & Female Reproductive System