Clare Hargreaves-Norris

Reproductive System

ACCESS Nursing and Midwifery.

Human Biology.

Clare Hargreaves-Norris

Aims.

Introduction.Male reproductive system A/P.Reference slide.Conclude with film clip.

Clare Hargreaves-Norris

Introduction

Male and female reproductive systems are different in shape and structure, but both are specifically designed to produce, nourish, and transport either the ova or sperm.

Male reproductive system is located both inside and outside the pelvis.

Male reproductive system consists of: testes, duct system, accessory glands such as seminal vesicles and prostate, and the penis.

Female reproductive system is located entirely in the pelvis.

Female reproductive system consists of: ovaries, fallopian tubes, uterus, vagina, external genitalia,b (mammary glands).

Clare Hargreaves-Norris

Clare Hargreaves-Norris

TestesDescription Function• The two testes are oval-shaped and grow to about

5 centimeters in length and 3 centimeters in diameter.• They are suspended in

the scrotum, outside the body. • Each testicle containapproximately 200-300 lobules.

• Testes produce and store millions of sperm cells.

• Testes are also part of the endocrine system, producing hormone testosterone.

• Stimulates sperm production.

• Testosterone is responsible for the development of the secondary sexual characteristics in boys (deeper voices, bigger muscles, body/facial hair).

Clare Hargreaves-Norris

Clare Hargreaves-Norris

Duct system

Description Function• Alongside the testicles

are the epididymis and the

vas Deferens.• These structures make

up the duct system. • The vas deferens is a

muscular tube that passes upward alongside the testes.

• The epididymis is a set of coiled tubes

inside each testicle.

• The vas deferens provides a

passageway that transports the semen from the testes.• The epididymis connects

the testicle to the vas deferens.

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Scrotum

Description Function

• The scrotum is a pouch-like

structure that hangs outside the pelvis. • It houses the epididymis and the testes.

• The scrotum helps to regulate the temperature of the testes.

• The temperature needs to be kept cooler than body

temperature to produce sperm.

• The scrotum changes size and position to maintain the correct temperature.

Clare Hargreaves-Norris

Prostate gland

Description Function

• Surrounds the ejaculatory

ducts at the base of the urethra, just below the bladder.

• Produces some of the semen.

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Seminal vesicle

Description Function

• Sac like glands that are found at the base of the bladder and are connected to the prostrate gland.

• Provide fluids that lubricate

the duct system and nourish the sperm.

Clare Hargreaves-Norris

Penis

Description Function

• The penis is actually made up of two parts: the shaft and the glans.

• The shaft is the main part of the penis and the glans is the tip.

• Inside the penis is the urethra, the channel that carries the semen to the outside of the body.

• At the end of the glans is a small slit or opening, which is where semen and urine exit the body through the urethra.

• The penis, which usually hangs limp, becomes hard when a male is sexually excited. • Tissues in the penis fill with blood and

it becomes stiff and erect. • The rigidity of the erect penis makes

it easier to insert into the female's vagina during sexual intercourse.

• When the erect penis is stimulated, muscles around the reproductive organs contract and force the semen through the duct system and urethra.

• This process is called ejaculation. • Each ejaculation can contain up to

500 million sperm.

Clare Hargreaves-Norris

Clare Hargreaves-Norris

Clare Hargreaves-Norris

http://www.youtube.com/watch?v=65BV5dXXxzM

Clare Hargreaves-Norris

Clare Hargreaves-Norris

Ovaries

Description Function• The ovaries are 2 oval-

shaped organs that lie to the upper right and left of the uterus.

• Each ovary measures about 4 to 5 centimeters in a grown woman.

• After puberty one ovum is released each month.

• This process is called ovulation.

• The ovaries produce, store, and release ova into the fallopian tubes in the process called ovulation.

• The ovaries are also part of the endocrine system because they produce the female sex hormones estrogen and progesterone.

• These hormones are responsible for female secondary sexual characteristics.

Clare Hargreaves-Norris

Clare Hargreaves-Norris

Follicle.

Small structures on the surface of the ovaries.

The follicles contain fluid and an ovum. When an ovum is mature for

fertilisation the follicle splits to release the ovum.

The mature ovum then travels along the Fallopian tube to the uterus.

Clare Hargreaves-Norris

Fallopian tubes

Description Function• There are 2 Fallopian

tubes, each attached to a side of the uterus.

• The Fallopian tubes are about 10centimeters long and about as wide as a piece of spaghetti.

• At the other end of each Fallopian tube is a fringed area, (fimbriae ends), that wrap around near the ovary.

• When an ovum exits an ovary, it enters the Fallopian tube.

• Once inside the Fallopian tube the ovum is transported towards the uterus by peristalsis and tiny hairs (cilia) in the tube's lining help push the ovum down the narrow passageway toward the uterus.

Clare Hargreaves-Norris

Uterus

Description Function

• The uterus is shaped like an upside-down pear.

• It has three layers:• - Endometrium (mucus

membrane – columna epithelial lining).

• - Myometrium (thick smooth muscle – thickest in the body).

• - Perimetrium (serous membrane).

• Receives the fertilised ovum which develops in the uterus.

• The uterus grows with the foetus until birth.

• The muscle expands and contract to accommodate a growing foetus.

• The muscle helps to push the baby out during labour.

Clare Hargreaves-Norris

Vagina

Description Function• The vagina is a

muscular, hollow tube that extends from the labia to the uterus.

• Muscular walls enable it to expand and contract.

• This allows the vagina to accommodate something as wide as a baby.

• The vagina's muscular walls are lined with mucous membranes.

• Lubricating fluids keep the vagina protected, moist and assist with penetration.

• The vagina serves 2 purposes:

• It is where the penis is inserted during sexual intercourse.

• It is the pathway that a baby takes out of a woman's body during childbirth.

Clare Hargreaves-Norris

External genitalia

Description Function• Mons pubis: The fleshy

area located above the top of the vaginal opening.

• Labia (Major and Minor): Two pairs of skin flaps that protect the external genitalia and urethral orifice.

• Clitoris: Small sensory organ located toward the front of the vulva where the folds of the labia join.

• Mons pubis and labia protect the internal structures such as the clitoris.

Clare Hargreaves-Norris

Mammary glands

Description Function

• The mammary glands are

located in the breasts.• They consist of 15-20

glandular lobes. • Inside each lobe are several smaller lobules.

• The mammary glands act as

reservoirs for the milk. • They secrete the milk

when stimulated during lactation.

Clare Hargreaves-Norris

Clare Hargreaves-Norris

Clare Hargreaves-Norris

Menstruation

When a baby girl is born, her ovaries contain hundreds of thousands of ova.

The ova remain inactive until puberty begins. At puberty the pituitary gland starts making

hormones. The hormones stimulate the ovaries to produce

female sex hormones, including oestrogen. The secretion of these hormones causes a girl to

develop into a sexually mature woman.

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Mensturation flows.

Towards the end of puberty, girls begin to release ova as part of the menstrual cycle.

Approximately once a month, during ovulation, an ovary sends a tiny ovum into one of the fallopian tubes.

Unless the egg is fertilised by a sperm while in the fallopian tube, the progesterone levels drop causing the egg to dry up.

The dried up ovum leaves the body about 2 weeks later through the uterus.

This process is called menstruation. Blood and tissues from the endometrium of the uterus

combine to form the menstrual flow. This which usually lasts from 3 to 5 days. On average, the monthly cycle for an adult woman is 28

days, but this may range from 23 to 35 days.

Clare Hargreaves-Norris

Dysmenorrhoea.

Painful periods. Many women also experience abdominal

cramps during the first few days of their period. These are caused by prostaglandin, a chemical

in the body that makes the smooth muscle in the uterus contract.

Clare Hargreaves-Norris

Fertilisation

Sexual organs of both sexes are required for reproduction. The female ovaries produce female gametes (ova). The male testes produce male gametes (sperm). Natural fertilisation occurs after sexual intercourse when the penis

deposits seminal fluid into the vagina. The sperm have a tendency to swim towards the fallopian tube

containing the ovulated ovum due to chemical signals that the sperm respond to.

They are also assisted in their journey by the cilia that are located in the cervix, wafting them along.

Once the sperm fuses with the ovum, the ovum membrane adjusts to prevent any other sperm from entering.

Zygote is the name given to a fertilised ovum. The zygote develops into a foetus. Pregnancy will develop over a 40 week period.