kidney and food Flashcards
How do you test for protein? Where do you find it?
- biuret reagent. Light blue to purple
* seafood, meat, eggs
What is fibre made of? why do we need it? Where is it found?
needed to help keep dig system healthy and prevent constipation. Can’t digest
• found in cereals, rice, beans, nuts
What are minerals? Why do we need them? Where are they found?
salts needed by body in small amounts, e.g. Calcium to keep bones healthy, iron for haemoglobin
• in milk and meat
What are vitamins? Why do we need them? Where do we find them?
A: good vision, maintenance and formation of skin, immune system(anti-oxidants). Dairy, eggs, fatty fish, mango, spinach
C: aids absorption of iron and copper, helps fight infection. Citrus fruit, blackcurrants
D: aids absorption of calcium. Found in sunlight on skin
How do you test for carbohydrates? Where do you find them?
• mono- benedict’s reagent. Blue ➯ brick red when heated
Sugar, cakes, etc.
• poly- iodine. Brown ➯ blue/black
Bananas , brown rice, potatoes
How do you find out the energy in a sample of food?
• fill boiling tube w water
• weigh water
• measure temp at start
• wound food on needle and burn under water
• measure temp at end
Energy (cal) = (mass of water x temp rise) / mass of food
How is absorption made efficient?
large SA w many villi and microvilli
• short diffusion distance, villus wall thin and close to blood vessels
• high conc gradient. Rich blood supply has low conc of food molecules ∴ food diffuses quickly
What are the types of digestion?
- mechanical, e.g. Teeth
* chemical, e.g. Enzymes
What are enzymes?
Biological catalysts in metabolic reactions. Work by lower activation energy. Different enzymes catalyse only their particular reaction, as each amino acids folds a different way to form the active site where the substrate binds. The substrate shape is complementary to the active site.
What are anabolic and catabolic reactions?
Catabolic- breaking down
Anabolic- building up
What would happen if we did not have enzymes?
Metabolic reactions would happen too slowly for life to carry on.
What are biological enzymes made of?
Proteins
Are enzymes general or specific?
Specific - they only work with one substance- substrate
