1. UNIT 3 NUTRITION
Ana Barba
González

2. NUTRITION
The function of nutrition is essential to live .
Nutrients give our cells all the energy they
need.
The digestive system , the respiratory
system , the circulatory system and the
excretory system carry out the function of
nutrition.

4. THE DIGESTIVE SYSTEM
The digestive
system is made
up of the digestive
tract and digestive
glands.

5. THE RESPIRATORY SYSTEM
The respiratory system is in charche of
breathing .
Breathing makes two movements :
 First , we inhale air and it goes into to the
lungs .
 Then , we exhale air sending it out of the
lungs .

6. THE EXCRETORY SYSTEM
The excretory system filters waste
substances from the blood .
The excretory system is made up of :
 Sweat glands
 The urinary system : Is made up of the
kidneys and the urinary tract .

7. THE EXCRETORY SYSTEM
1. The kidneys remove waste substances
from the blood and they make urine .
2. The ureters take urine from the kidneys
to the bladder .
3. The bladder stores the urine .
4. The urethra connects the bladder to the
outside .

9. THE CIRCULATORY SYSTEM
The circulatory system transports nutrients
and oxygen to our cells . It is made up of
the heart , blood , and blood vessels .
The heart is a muscular organ that pumps
blood around the body .
The blood collects oxygen and nutrients
and transports them to all the cells . It also
collects waste substances and takes them
to the sweat glands and the urinary
system .

10. The blood vessels : there are 3 types of blood
vessels : arteries , veins and capillaries .

11. Capillaries: are very thin vessels that reach
all the cells of the body.
Arteries: carry blood from the heart to the
rest of the body .
Veins: carry blood from all over the body
back to the heart .

12. THE BLOOD
Blood is a red tissue made up of cells that
float in a liquid called plasma .
There are three types of blood cells , red
blood cells , white blood cells and platelets .
 Red blood cells carry oxygen .
 White blood cells remove bacteria and
viruses from the blood .
 Platelets are small fragments of cells that
forms blood clots .

13. 12

14. THE HEART
The heart uses rhythmic systole and
diastole movements to pump the blood
around the body .
Blood enters the atria through the veins and
passes to the ventricles .
Blood comes out of the ventricles , through
the arteries and travels all over the body .

15. Heart septum

16. HUMAN CIRCULATION
Human circulation is closed and double .
Human circulation is closed . In mamals ,
the heart septum separates the two halves
of the heart .
Human circulation is double . The blood
follows two routes .
 Pulmonary circulation .
 Systemic circulation .