Aim: How is the Human Reproductive System built to do its job?

What is the job of the Female reproductive system? Produce eggs Produce hormones to control the secondary sex characteristics Pregnancy Birth Nourish newborn

Female Reproductive System 3. Uterus (D) Embryo implants and develops 4. Vagina Birth canal Where sperm is deposited

Female Reproductive System Ovaries (B) produce egg cells (meiosis) release the hormones estrogen and progesterone 2. Fallopian Tube/Oviduct (A) Site of fertilization Carries egg to uterus

What is the job of the Male Reproductive System? Produce sperm Produce hormones to control the Secondary sex characteristics Fertilize the female internally (release urine)

Male Reproductive system Testes produce sperm Production of the hormone testosterone 2. Scrotum sac that keeps testes cool 3. Vas Deferens Carries sperm from the testes to the urethra

Male Reproductive system 4. Prostate Gland (and Seminal Vesicles and Cowpers Glands) Produce the fluid of the semen: Liquid for sperm to swim (Internal Fertilization on land Base- neutralize acid in female body Sugar – for energy to swim 5. Urethra Tube which runs through the penis to release: Urine semen

INTERNAL FERTILIZATION Eggs and sperm meet inside the female’s body Live on Land (no water for sperm to swim to egg in the environment Ex. birds, mammals

EXTERNAL FERTILIZATION\ Eggs fertilized outside female’s body mostly in aquatic environments Ex. Fish, starfish

Which is better? Internal: Less eggs produced because: most meet sperm and fertilization increases Less are eaten Constant environment inside body

Embryonic Development The zygote grows into an entire body. Development can be either INTERNAL or EXTERNAL, depending on the organism.

INTERNAL DEVELOPMENT Embryo develops inside the female, placenta provides nourishment

Human Fertilization Internal fertilization – male penis is used to introduce sperm into female’s vagina.

Where does fertilization usually occur? Fertilization occurs in the fallopian tubes (oviduct) Ovary Fertilization Egg

How many eggs are released a month by a female? Normally one however, sometimes TWO can be released at the same time. Ovulation This is called ovulation!

What happens after fertilization? The embryo travels to the uterus and implants itself in the uterus lining

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