Digestion Flashcards
What is an active site?
The place on an enzyme which the substrate connects to
What is a substrate?
The thing that attaches to the active site on an enzyme.
What is the lock and key theory?
When the Enzyme binds to the substrate because they are complimentary shapes.
What is an enzyme?
Large protein molecules
What happens on the active site?
It breaks down the substrate ( large food molecule (insoluble)) them it’s absorbed into the bloodstream.
Where is protease found?
Stomach pancreas small intestine
What enzyme breaks down protein into amino acids
Protease
What does protease break down
Protein into amino acids
What breaks down starch into glucose
Amylase
Where are amylase found
Saliva and pancreas
What do amylase break down
Starch
What do lipase break down and what into
Lipids into glycerol and fatty acids
What breaks down lipids
Lipase
Where is lipase found
Pancreas and small intestine
What speeds up digestion of lipids
Bile
Where is bile stored
Gall bladder
Is bile an acid or alkaline
Alkaline
What are villi
Projections in the small intestine and increases the surface area
What do the villi do
Increase the surface area so digested food is absorbed quicker into the blood smaller diffusion pathway
What is the surface of villi made of
Single layer of surface cells
Inside villi
Network of capillaries so it has a good blood supply
Where is bile stored and made
Stored : gall bladder
Made: liver
Is bile and enzyme
NO
What does bile do
It speeds up the digestion of lipids by increasing the surface area
How does bile speed up digestion
Bile emulsifies the lipid so increase the surface area of the lipids so increase the rate of lipid break down by lipase
Why is it important that bile is an alkaline
It neutralises the stomach acids so it created alkaline conditions for the small intestine so it increase the rate of lipid digestion by lipase
How does temperature affect the enzymes
Increases enzyme reaction increases until reaches optimum temperature
What happens when the temperature on an enzyme gets too much
Active site denatures so enzyme can no longer speed up reaction
What do ph do to enzymes
Each enzyme has a specific optimum ph
The active site denatures if conditions are too alkaline or acidic
Test for starch
2cm… of food solution ( food samples grinder with distilled water filter solution to remove food particles) add iodine solution
Colours for starch
Orange - blue / black
Test for sugars( glucose)
10 drops of Benedict’s solution to food solution and put in hot water bath for five minutes
Colour change of sugars
Blue - green/ red/ yellow
Test for protein
Add 2cm… biurets solution to food solution
Protein colour change
Blue-purple
Test for lipids
Unfiltered food solution and a few drops of ethanol and distilled water to food and shake
Colour change of lipid
Clear- white and cloudy
What is the function of the mouth and how does it do its function?
It begins the process of digestion of carbohydrates.
Enzymes in the saliva begin to digest the starch into smaller sugar molecules.
What is the tissue that lines the stomach
Epithelial tissue
What is the acid that is inside the stomach?
Hydrochloric acid
What is the main job of the hydrochloric acid in the stomach
Assists the enzymes in the stomach to digest proteins.
What is the main job of the stomach and how does it do it?
Begins the digestion of protein; small molecules such as alcohol absorbed.
To digest the proteins the stomach muscles perform a churning action which turn the food into fluid which will increase the surface area for the enzymes to digest easier along with the acid.
What happens when the fluid from the stomach begins to travel down to the small intestine? (Duodenum)
Chemicals are released into the small intestine from the liver and the pancreas.
- Liver - the bile catalysts digestion of lipids. It also neutralises the acid release from the stomach as it is an alkali.
- Pancreas - enzymes which continue digestion and proteins and start the digestion of lipids.
What is the purpose of the small intestine itself once the fluid as arrived?
The walls of the small intestine release enzymes to continue digestion of protein and lipids. Also the small molecules are absorbed into the bloodstream either by diffusion or active transport.
What is the purpose of the large intestine?
Absorb the water and egestion of undigested food.
What does contract mean?(muscles)
Get smaller
What allows the muscle tissues to contract?
They contain special protein fibres which can change length. The cells inside of these tissues are full of mitochondria which provides the energy for contraction.
What is a tissue?
A group of cells with similar structures and functions
What is an organ?
Group of tissues working together for a specific function
E.g stomach (muscle tissue and glandular tissue)
What is glandular tissue
It releases enzymes to catalyse digestion.
What is an organ system?
When organs work together to form and organism e.g digestion system.
The hierarchy of internal things (digestion)
Cell
Tissue
Organ
Organ system
Organism
What kind of molecules are carbohydrates, protein and lipids?
Large molecules which cannot be absorbed into the bloodstream.
Can large molecules be digested into the bloodstream?
No because they are too large so they have to be digested into small molecules by enzymes which can be digested.
What are the products of digestion used for?
New large molecules (carbohydrates, proteins and lipids)
What is some of the glucose produced used in
Respiration.
