Organisation & the digestive system

How is the small intestines adapted for its function?

How is the small intestines adapted for its function?

1. Villi (finger like projections) line the intestine wall, increasing the surface are and the speed of absorption.

2. The villi have a very good blood supply, maintains concentration gradient.

3. The villi are a single layer of surface cells thick. Short distance to diffuse.

What is the function of the gall blader

It stores and releases bile into the small intestines

What is the use of bile

Bile (an alkaline) neutralises hydrochloic acid (stomach acid)

emulsifies fats into droplets which increases the surface area for its digestive enzyme.

Whats is the function of the stomach

1. contracts musular walls

2. Produces pepsin which breaks down proteins

3. Produces hydrochoric acid which kills bacteria and creates the right environment for pepsin

What is the equation for the breakdown of proteins by protease

proteins————————> amino acids

Where is protease produced?

Pancreas, stomach, small intestines

Where is protease found?

Stomach & small intestines

What is the word equation for the breakdown of lipids by lipase

lipids—————————> Fatty acids+Glycerol

Where is lipase produced?

Pancreas

Where is lipase found?

Small intestines

What is the word equation for the breakdown of carbohydrates by amylase (amylase is a type of carbohydrase)

Carohydrates—————————>Simple sugars (glucose, maltose etc.)

Where is amylase produced?

Pancreas, Salivary glands, small intestines

Where is amylase found

Mouth&small intestines

What reagent is used to test for sugar and what colour is the positive result

Benedicts solution , positive resullt: orange-red

What reagent is used to test for starch and what colour does it turn for a positive result

Iodine soution, Positive result: Blue-black

What reagent is used to test for protein and what colour does it turn for a positive result

Biuret solution , purple