Human Reproductive System

Part JobTestis Produces sperm cellsScrotum Sac that holds the testisPenis Penis Places sperms into

the vagina during mating

Vas deferens Carries sperm from testes to urethra

Urethra Carries sperm out of the body

Glands

a. seminal vesicle

b. prostate gland

c. Bulbourethral gland

Provide liquid in which sperm can swimSecretes one of the components of the semenSecretes a milky fluid that is discharged into theurethra as part of the semenMucous secreting glands located at the base of thepenis

Male Reproductive System

The female reproductive system has the following

functions:

• 1. Production of female sex cells• 2. Reception of sperm cells from

the male• 3. Nurturing the development of

and providing nourishment for, the new individual

Part Job

Ovary Produces egg cells

Oviduct Oviduct Passageway of eggs from the ovary to the uterus(also the same place where the egg is fertilized.

Uterus Place where fertilized egg develops

Vagina Receives penis of male during mating

Female Reproductive System

The Menstrual Cycle

Fertilization

• Occurs in upper 1/3 of Fallopian tube

• Once one sperm enters, egg membrane changes

• Fertilized egg = zygote

Implantation

• Implanted into thick walls of uterus

• Chorion membranes dig into uterus to form placenta

• Embryo supported via umbilical cord

• Once pregnant, progesterone levels stay high in mom

1st Trimester

• Heart develops first• Neural tube develops• All body systems appear by

Week 8 – Now a Fetus

2nd Trimester

• Mostly growth• Looks more like a baby• Some preemies survive at this

stage

3rd Trimester

• More growth• Kicking, rolling, stretching• Eyes open – Week 32• Lungs mature• Rotates to head-down position

Birth

• Labor– Uterine contractions begin– Cervix dilates to 10 cm.

• Birth– Uterus pushes baby through

vaginal canal• Placenta delivered after

Most of this not fun?