Unit 1: INSIDE YOUR BODY
ØINTRODUCTION
- All
humans perform three life functions: nutrition, interaction and
reproduction.
- In
the nutrition process participate the digestive system, the excretory
system, the respiratory system and the circulatory system.
- Reproduction is
made up of the female reproductive system and the male reproductive system.
Ø THE DIGESTIVE SYSTEM
- The
digestive system extracts nutrients from the food you eat.
- The
oesophagus joins the mouth to the stomach.
- Nutrients
are separated from the waste in the small instentine.
- Waste
leaves the body through the anus.
Ø THE EXCRETORY SYSTEM
- The excretory system is made up of the urinary system and sweat glands.
· The urinary system
1º.-
The kidneys separate water and minerals from the blood to produce urine.
2º.-
The urine goes down the ureters to the bladder.
3º.-
When the bladder is full, your body tells you to go to the toilet.
4º.- The bladder releases urine through the urethra.
· Sweat glands
-
When you do exercise or it is very hot,
your body produces sweat.
-
This is a mixture of water and minerals.
-
It is produced in sweat glands and
is released through pores in the skin.
Ø THE RESPIRATORY SYSTEM
1º.- Air enters the body
through your mouth or nose.
2º.- The air goes down the
trachea. The trachea connects the mouth to the bronchi.
3º.- The air enters the
lungs through two tubes called bronchi.
4º.- The air travels
though the lungs and ends in the alveoli. Alveoli are small air sacs.
5º.- In the alveoli,
blood exchanges carbon dioxide for oxygen.
6º.- You expel carbon
dioxide when you breathe out.
Don´t forget that colds and the flu are caused by viruses and bacteria.
Ø THE CIRCULATORY SYSTEM
-
The
circulatory system transport nutrients and oxygen to every cell
in your body.
-
The circulatory system consists of heart and blood vessels.
-
Arteries
take blood from the heart to the body.
-
Capillaries
are very small blood vessels that connect the arteries and the veins.
- The heart pumps blood round the body through the blood vessels.
Ø THE REPRODUCTIVE SYSTEM
- There are two types:
·
The female reproductive system.-
Organs: fallopian tubes, ovary, vagina, vulva and uterus.
·
The male reproductive system.-
Organs: penis, scrotum, testicle, urethra
