B2 Organisation Flashcards
What makes up the body?
cells –> tissues –> organs –> organ system
What do teeth do?
break down food mechanically. Saliva contains the enzyme Amylase.
What does the stomach do?
contains hydrochloric acid and enzymes that chemically break down food.
What does the liver do?
produced bile which is stored in the gall bladder before going to the small intestine. Bile EMULSIFIES LIPIDS to form droplets, increasing their surface area.
What does the pancreas do?
secretes amylase which breaks down STARCH to GLUCOSE in the small intestine.
What happens in the large intestine?
Water is absorbed into the blood stream.
What happens in the small intestine?
nutrients like glucose are absorbed into the bloodstream by the Villi.
What are enzymes?
Enzymes are biological catalysts that break down molecules.
What do carbohydrases do?
break down carbohydrates into simple sugars
e.g. amylase breaks down starch to glucose.
what does protease do?
breaks down proteins into amino acids.
what do lipases do?
break down lipids into glycerol and fatty acids.
What is the lock and key model?
Enzymes are specific. Substrates bind to a specific active site.
How is the rate of reaction of enzymes altered?
Activity increases with temperature until the enzyme denatures (active site changes shape). pH can also affect rate of reaction.
What is used to identify starch?
Iodine (turns from orange to black).
What is used to identify sugars?
Benedict’s solution (turns blue to orange).
What is used to identify proteins?
Biuret’s (turns blue to purple).
What is used to identify lipids/fats?
Cold Ethanol (turn clear to cloudy).