Human ReproductionHuman ReproductionChapter 17.1Page 548 - 554

ObjectivesObjectivesDescribe the path that sperm

cells take through the male reproductive system

Identify the organs of the female reproductive system and describe their functions

Describe the major events of the female reproductive cycle.

Key TermsKey TermsFertilizationTestisScrotumSperm cellPenisUrethraSeminal vesicles

Key TermsKey TermsSemenEjaculationBulbourethral glandUterusOvaryFallopian tubesVagina

Key TermsKey TermsFollicleOvulationMenstruation

The Male Reproductive The Male Reproductive SystemSystemThe testis produce Testosterone, a

hormone that is crucial for the development of primary sex characteristics.◦The development of male reproductive

organs before birthTestosterone is responsible for the

development of secondary sex characteristics◦Adult males

Larger skeletal muscles, hair on the face, a deep voice

The Male Reproductive The Male Reproductive SystemSystem

Testosterone signals Sperm cell production by the testis through an complex hormone system◦About 200 – 400 million per day, (one sperm cell

can take 10 weeks from start to finish)◦They contain the genetic information, (1/2 the DNA)

◦They have a special shape allowing them to move Semen is a mixture that contains sperm cells

◦The prostate gland and seminal vesicles produce fluids that are added to the sperm in a tube called the vas deferens

The Male Reproductive The Male Reproductive SystemSystem

• Sperm cells move from the testis to the penis–The penis is composed of spongy tissue• During arousal, the spongy tissue fills with blood,

becoming erect, preparing a male for intercourse–Sperm is deposited in the female reproductive system

–The urethra is a tube on the underside of the penis• It can carry urine from the bladder or semen from the vas

deferens • Even before ejaculation watery discharge from the

Bulbourethral gland may expel sperm into the female system

• Semen is expelled from the body by ejaculation–Ejaculation is a reflexive response to nerve signals• Contractions of the vas deferens expel semen

The Male Reproductive The Male Reproductive SystemSystemSperm cells carry the genetic

material that determines the characteristics of offspring

Males carry an X & Y chromosome and females carry an X & X chromosome◦ Males determine the sex of the

baby because only they carry the Y chromosome

The Female Reproductive The Female Reproductive SystemSystemThe center of the female reproductive

system is the Uterus◦Contains and nourishes the developing

baby inside the mother, (the womb)The Ovaries contain the reproductive

cells of the female◦An undeveloped egg cell develops each

month◦These egg cells are in place when the

female is born, (each ovary contains about 400,000 cells), yet only about 400 may mature

◦Unfertilized eggs are eliminated with the menstrual flow

The Menstrual CycleThe Menstrual CycleHormones needed

for the cycle:◦ FSH, (follicle stimulating

hormone), begins the process of egg production

◦ Estrogen causes the production of LH, (luteinizing hormone), and matures the egg

◦ Progesterone is the body’s signal to prepare for pregnancy and stops LH and FSH production

◦ Brain hormones control the entire process

The Female Reproductive The Female Reproductive SystemSystem

As egg cells are released into the Fallopian Tubes from the ovary

The egg moves down the Fallopian Tube to the Uterus

Fertilization occurs in the Fallopian Tube by sperm

Sperm cells released into the Vagina during the previous 72 hours may enter the egg

The fused cells develop into a baby

SummarySummaryThe male reproductive system consists

primarily of two testes, two vas deferens, two seminal vesicles, the prostate gland, the bulbourethral gland, (or Cowper’s gland), and the penis

The testes produce the male reproductive cells, (sperm cells), and the male hormone, (testosterone)

Semen, the fluid that contains sperm cells, exits the male body by a reflex called ejaculation, (referred to in the path of sperm)

SummarySummaryThe female reproductive system

consists mainly of two ovaries, two fallopian tubes, the uterus, and the vagina

The ovaries contain egg producing cells and produce the female hormones, progesterone and estrogen

A single egg producing cell matures in one ovary, is expelled, (ovulated), every month