Question

1. How is food digested in our stomach and small intestine?

2. Define arteries and veins.
3.
Write a short note on liver.
4. How do our lungs work?
5.
Describe the human heart with a diagram.
below.​

Answer 1

STOMACH

1 the food from the mouth reaches the stomach through the oesophagus there are many gastric juices released in our stomach

• HCL : hydrochloric acid is released in our stomach it kills the germs makes the medium acidic so that the pepsin could work and softence the food
• PEPSIN : pepsin is released in our stomach by the pancreas it digest the proteins in the the acidic medium
• MUCUS : mucus is present in the inner lining of stomach it protects a stomach from the corrosive action of hcl

SMALL INTESTINE

the partially digested food from the stomach which is the small intestine here three enzymes are released

• AMYLASE : converts carbohydrates into glucose
• LIPASE : converts fats into fatty acids and glycerol
• TRYPSIN : converts protein into amino acids

the digested food is taken up by the walls of intestine which are connected to the blood vessels by villi it is the finger like projections which increases the surface area for absorption from here the absorb food caried to each and every cell

2 ARTERIES: it takes oxygenated blood from the heart the walls of the arteries are thick and Elastic the high pressure and they are deeply seeted inside the skin

VEINS: it takes deoxygenated blood towards the heart . blood goes in one direction and their very superficial