Organisation PART 1 Flashcards
Enzymes
Enzymes catalyse (increase the rate of) specific reactions in living organisms
Digestive enzymes
Digestive enzymes speed up the conversion of large insoluble molecules (food) into smaller soluble molecules that can be absorbed into the bloodstream
What affects the activity rate of enzymes?
Temperature and pH
Enzymes activity has an optimum temperature of around 37°C
Enzymes activity has an optimum pH of around 7.
Denature
Large changes in temperature or pH can stop the enzymes from working, and the enzymes are denatured.
If the temperature is too high or the pH is too high or low, the enzyme changes shape (denatures) and the substrate no longer fits the active site.
Carbohydrases (e.g. amylase)
Made in salivary glands, pancreas, small intestine
Break down carbohydrates to simple sugar (e.g. amylase breaks down starch into glucose)
Proteases
Made in stomach and pancreas
Break down protein to amino acids
Lipases
Made in pancreas (works in small intestine).
Break down lipids (fats) to glycerol and fatty acids.
Bile (not an enzyme)
Made in liver, stored in gall bladder.
Emulsifies lipids to increase surface area to speed up the lipid break down rate by lipase.
Changes pH of stomach acid to neutral for lipase to work.
How are the products of digestion used?
The products of digestion are used to build new carbohydrates, lipids and proteins. Some glucose is used for respiration.
Benedicts’ test
Food test to test for sugars (glucose).
Orange to brick red precipitate.
Iodine test
Food test to test for starch.
Turns black.
Biuret reagent
Food test to test for protein.
Mauve or purple solution.
Obesity (Liam)
More energy consumed in food and drink than used.
Linked to increased rates of cardiovascular disease and development of diabetes type 2.
Cells (organisation)
The basic building blocks of all living organisms.
The building blocks of life, perhaps.
Tissues
A group of cells with a similar structure and function.
