Unuit 1: INSIDE YOUR BODY

 

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