HUMAN REPRODUCTIVE SYSTEMS

MALE AND FEMALE

WHAT´S A SPERM?Before…People used to think there was a tiny human inside each cell

Contains Several Parts:-HeadChemical to dissolve egg gooDad’s genetic information (DNA)- MitochondriaEnergy- TailSwimming

Produce fluid that nourishes sperm

Secrets an alkaline fluid that counteracts the acids found in the male urethra and in the vagina of the female.

Blood acumulates in the penis, causing it to become firm and erect.

It´s the tube that carries urine during urination and semen during ejaculation.

Sperm production begins in the testes at puberty and continues throughtout life.

It´s a coiled tube attached to the surface of each testis.

The vas deferens passes over the urinary bladder, connecting the epididymis to the urethra

Secrets an alkaline fluid that becomes part of the semen.

For fertilization to occur, sperm first must be transferred from a male to

female.The penis is the organ that makes it

possible for sperm to be delivered to the body of the female.

MALE HORMONS

Testes produce the male hormone: testosterone.a male begins to make testosterone before birth, it causes

an embryo to develop a penis and scrotum.

MALE HORMONS

At puberty testosterone levels rise, it causes the development of adult male

characteristics:beard, low voice and large muscles.

SEMEN

CONTAINS300-500 MILLION SPERM

SPERM SURVIVES FOR A COUPLE OF DAYS INSIDE FEMALE’S BODY (HOSTILE ENVIRONMENT)

FEMALE REPRODUCTIVE SYSTEM

After fertilization, the embryo develops into a fetus inside the uterus.

In the center of the cervix is a small openingthrough which sperm can enter the uterus.

Ovaries are the site of egg production.

Fertilization occurs in one of the fallopian tubes, the fertilized egg then travels into the uterus.

FALLOPIAN TUBES

The vagina connects the uterus to the outside of the body

FALLOPIAN TUBES

It is covered by a hood of skinthat is connected to the labia.

FALLOPIAN TUBES

They are folds of skin.

FALLOPIAN TUBES

Ovaries2 pouchesContain ovaBorn with all of her eggs (~ 400,000)Use up ~500Won’t run out!

OvulationOne egg released from ovary to oviduct (fallopian tube)

AFTER OVULATION

Egg pushed along by ciliaFew days travel time to arrive in uterus

Cervix – Opening between uterus & vagina

Normally tinyAt birth – muscles pull open (dilation) cervix to

allow baby to pass through = Labor

Menstrual Cycle

• Complex combination of 10-12 chemicals (hormones)

• Usually one egg once a month• All about timing!!!– Uterus must be ready when egg gets there in case

it was fertilized– If no fertilization, tear down lining of uterus and

rebuild for next month

28-Day Cycle (average)

• Three Stages1. Tear Down2. Rebuild3. Extra nutrients/blood for potential baby

• No Baby?– Back to #1

Day 1

• First menstrual blood & tissue• No baby = breaks down lining of uterus• 5-7 days of blood/tissue exits body

Pre-Ovulation

~Day 14• Ovulation = Egg released• Temp spikes slightly• Most fertile in next few days!– Able to get pregnant

• Egg gets fertilized while traveling through oviduct.

Post-Ovulation

If fertilized…

• Zygote begins to divide as it travels through oviduct

• Implants into lining of uterus

If not fertilized…

• Egg travels through oviduct to uterus• Exits body with blood and tissues during

menstruation

Anatomy

Male Female

Similarities

• 2 pouches– Testicles– Ovaries

• Start out inside body– Testicles “descend” before birth

• Fetus begins with “starter parts” that could develop into either gender.

Anatomy – similaritiesFunction – VERY different!

• Male– Uncomplicated– Produce sperm• 2-4 MILLION every

day

• Female– Very Complicated!– One egg– Once a month– Careful coordination

of hormones & body– Timing perfect!

Watch this video!!https://www.youtube.com/watch?v=hguHF962z5U

ACTIVITY

• What are the main parts of a sperm?, draw it and write its main parts.

• Are important the male hormons? Why?

• Explain what the menstrual cycle is about.