B3 Flashcards
what is a tissue
a group of cells with similar structure and job
what is an organ
a collection of tissues that perform a specific function
what does the pancreas do
it makes hormones that control blood sugar level and it makes some of the enzymes that digest things in the stomach
what is an organ system
a group of organs that perform a specific function in the body
where are the main places food is digested
small intestine and stomach
where is bile produced
the liver
what are proteins made of
amino acids
what is carbohydrates made of
sugars
what are lipids made of
fatty acids and glycerol
what do proteins do
repair and create tissues. create enzymes
what are catalysts
they speed up a reaction without chemically changing themselves
what is an enzyme
enzymes are biological catalysts and catalyse specific reactions in living organisms due to the shape of their active site
how does the lock and key method with enzymes work
a substrate connects to an enzymes active site(which is specifically shaped for a certain type of substrate) it then splits into products and leaves the active site. the enzyme can be used again
what is an enzyme made of
amino acids
what is metabolism
the some of all of the reactions in a cell or our body
what can affect enzyme activity
PH and temperature
what happens when an enzyme denatures
the active site changes shape and the enzyme can no longer work
how does an enzyme denature temperature
if the temperature is too hot, over 40 degrees, the chains of amino acid begin to unravel meaning the shape of the active site no longer is the same meaning it doesn’t work as things can’t fit into it, it is irreversible.
how does an enzyme denature PH
the shape of the active site in an enzyme is controlled by forces between different parts of the protein molecule. a change in PH affects these forces and changes the shape of the molecule. as a result the specific shape of the active site is lost. Different enzymes work best at different ph levels, sometimes a change in ph can stop them working completely.
what is digestion
the breakdown of large insoluble molecules into smaller soluble molecules that can be absorbed into the blood across the wall of the small intestine
what do carbohydrases break carbohydrates down into
simple sugars
what do proteases break proteins down into
amino acids
what do lipases break lipids down into
fatty acids and glycerol
what ph is the stomach
very acidic
what ph is the small intestine
slightly alkaline
where are amylase made
salivery glands and pancreas
where are proteases made
pancreas, small intestine and stomach
where are carbohydrases made
pancreas and small intestine
what ph does protease enzymes work best in
acid
how does the stomach maintain a low ph
it produces hydrochloric acid
what does bile do
it neutralises acid and emulsifies fat and gives a high ph so the enzymes from the small intestine and the pancreas can work well
