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UNIT 2: HUMAN

REPRODUCTION

INDEX:

* Reading Comprehension.

* Written Essay.

1.- Sexual Characteristics.

1.1. Primary Characteristics.

1.2. Puberty.

1.3. Secondary

Characteristics

2. The Human Reproductive

System.

2.1. The Female Reproductive

System

2.2. The Male Reproductive

System

3. Processes in Human Reproduction.

3.1. Production of gametes

3.1.1. The female gamete: the

ovum

3.1.2. The male gamete: the

spermatozoid.

3.2.- Fertilization

3.3.- Pregnancy

3.4.- Childbirth.

1.-SEXUAL CHARACTERISTICS

1.1.- Primary sexual characteristics

We have these characteristics

when we are born.

They are the reproductive

organs

1.2.- Puberty and

Adolescence.Puberty is the time when the

reproductive system matures and

secondary characteristics appear.

It starts when the pituitary gland

sends hormones to the genital

organs.

Adolescence is the period of

mental transition from childhood

to adulthood.

1.2.- Puberty and

Adolescence.

1.3.- Secondary sexual

characteristics

*GIRLS reach puberty between

11 and 14 years and the

secondary characteristics are:

1.3.- Secondary sexual

characteristics

BOYS reach puberty between 13

and 15 years and the secondary

characteristics are:

Lower voices

More developed muscles

Lot of facial and body hair.

2.- THE HUMAN

REPRODUCTIVE

SYSTEM

2.1.- The Female

Reproductive

System

The uterus

The ovaries

The fallopian

tubes

The vagina

The vulva

Ovaries.

The ovaries are two oval organs, the size of a nut. They produce the ovules.

Fallopian Tubes

They are two

conducts about

10 cm long.

They connect

the ovaries to

the uterus.

UterusIt is a hollow

organ with walls made of muscle.

It is the shape and size of a pear.

The cervix

connects it to

the vagina

Vagina

It is a conduct

about 15 cm

long.

The walls are

made of muscle

and it connects

the uterus with

the exterior.

It is formed by

folds of skin, called

labia.

Vulva

They cover and

protect the

orificies of

the vagina and

urethra.

Vagina

2.2.- The Male

Reproductive System

prostate gland

seminal vesicle

vas deference

penis

testicles

scrotum

Vas deferens.

It is a tube that leaves each

testicle and connects them

to the urethra.

Prostate &

They produce liquids that mixwith the spermand form semen.

Seminal Vesicles

Glands:

Penis

It is a long cylindrical organ, covered in skin. Inside runsa tube called the urethra, which is part of both thereproductive system and theurinary system.

Testicles

They are thesize of a nut. They are formed of numeroustubes in whichsperm isproduced.

Scrotum

It is the sack

of skin that

covers the

testicles and

mantains

them inside

the body.

3.- PROCESSES IN HUMAN

REPRODUCTION

3.1.- Production of gametes

3.1.1.-The female gamete: the

ovuleOvules are large and round.

From puberty on, one ovule matures

and passes through a fallopian tube

aproximately every 28 days.

If it is not fertilized, it leaves the body

through the vagina with a small

amount of blood called menstruation

or period.

3.1.1.-The female gamete: the

ovule

Nucleus

MembraneGirls are born with more than 400,000 eggs already stored

in their ovaries.

3.1.2.-The male gametes: the

spermatozoids

The spermatozoids are very small.

From puberty on, about 200 million

of them are produced everyday.

TailHead

Nucleus

GAMETES

WHAT ARE

THEIR

NAMES?

WHAT DO

THEY LOOK

LIKE?

WHERE ARE

THEY MADE?

MALE FEMALE

SPERMATOZOI

DS

OVULES

VERY SMALL LARGE &

ROUND

OVARIES TESTICLES

Complete these sentences

The urethra is a tube that is common

to the reproductive system and the

urinary sytem.

• Sperm is produced and matures in

the testicles.

• Semen is composed of

spermatozoids and of the fluids that

are produced by the prostate and the

seminal vesicles.

Complete these sentences

The ovary produces the ovules.

The uterus is a muscular and

hollow organ about the shape

and the size of a pear.

Its function is to contain the

fertilized ovum that will develop

as a baby.

3.2.Fertilization

Fertilizationhappens in thefallopian tube. Theovule fertilizedenters the uterusand becomesjoined to the wall. In this waypregnancy starts.

3.3 Pregnancy

It takes place in the uterus.

It last about nine months. It

is divided into three phases:

FIRST TRIMESTER

SECOND TRIMESTER

THIRD TRIMESTER

FIRST TRIMESTER.

During the second week the embryo

is protected by a sack full of liquid,

called

The Amnion.

The embryo

produces an

organ called the

placenta, that

extracts

nutrients and

oxygen from the

mother´s blood.

The nutrients reach the

embryo through the umbilical

cord.

SECOND TRIMESTER

The foetus skeleton,

musculatures and all the

organs develop. It can

move.

THIRD TRIMESTER

At the end of the seventh monththe foetus could survive outsidethe mother.It fits its head into the neck of theuterus and it is ready to be born.

3.4 CHILDBIRTH

1.- When the baby is ready the

muscles of the wall of the uterus

produce contractions.

DILATION

2.- The amniotic sack breaks

and the baby comes out from

th vagina.

BIRTH

3.- The umbilical cord is cut. The

remains of the cord leave a scar

on the abdomen of the baby: the

navel.

AFTERBIRTH