B3 - organisation and digestion Flashcards
What are the 6 nutrient groups
Protein, vitamins, minerals, lipids, carbohydrates, fibre
What does fibre do
Indigestible but helps with digestion of other stuff
What are the two types of carbohydrates and what are they made of
Simple sugars - one molecule, short term energy
Complex carbs - multiple, long term energy
Made from carbon, hydrogen and oxygen
What are lipids (fats and oils) made from
Glycerol and fatty acids
What is the difference between saturated and unsaturated fats
Saturated fats - all bonds used up, harder to break down
Unsaturated fats - some bonds not used up, easier to break down
What are proteins made of
Amino acids in different combinations (amino acids are made from carbon, hydrogen, oxygen and nitrogen)
What are proteins used for and why
Enzymes, antibodies and DNA because each one forms a unique 3D shape
What is the test for starch and colour change
Iodine, brown to blue
What is the test for lipids and colour change
Ethanol, clear to milky white
What is the test for glucose and colour change
Benedict’s, red to blue
What is the test for protein and colour change
Biurets - blue to purple
Why do we digest food
To turn it from large insoluble molecules into small soluble molecules that can be absorbed into the bloodstream
What type of digestion does the mouth do
Mechanical - chewing
Chemical - saliva contains carbohydrase
What type of digestion does the stomach do
Mechanical - mashes food
Chemical - different types of enzymes
What type of digestion does the small intestine do
Chemical - different types of enzymes
What does the pancreas do for digestion
Produces enzymes
What does the liver do for digestion
Bile duct produces bile to emulsify fats into smaller droplets
What does the large intestine do for digestion
Extracts water from waste
How do enzymes work
The shape of the active site fits into the substrate, and the bonds are weakened which catalyses the breaking down reaction.
What is optimum temperature
The temperature at which an enzyme works best because it isn’t too hot to be denatured but is hot enough that it moves around fast and collides with substrates more often
What is optimum PH
The PH at which an enzyme is not denatured
What is carbohydrase and where is it produced
An enzyme that breaks down carbs into glucose, produced in salivary glands, pancreas and small intestine
What is amylase and where is it produced
An enzyme that breaks down starch into glucose, produced in salivary glands, pancreas and small intestine
What is protease and where is it produced
An enzyme that breaks down proteins into amino acids, produced in stomach, small intestine and pancreas
What is lipase and where is it produced
An enzyme that breaks down lipids into glycerol and fatty acids, produced in pancreas and small intestine
Why is the stomach PH2
So it’s enzymes are at optimum PH
What does bile do
Emulsifies (breaks down) large droplets of fats into smaller ones with a higher surface area to volume ration so lipase works faster
What are villi
Protrusions on the small intestine wall to increase surface area and allow more nutrients to diffuse into the bloodstream
