Flashcards in Enzymes & Transport in Cells Deck (11):
What is enzyme activity affected by?
pH, temperature, substrate concentration
What is a substrate?
The substrate is a molecule upon which an enzyme acts
Lock and Key theory
Only the correctly sized key (substrate) fits into the key hole (active site) of the lock (enzyme).
When a factor (such as pH level or temperature) cause the enzyme to change shape. The substrate no longer fits the active site.
Made in salivary glands, pancreas small intestine. Break down carbohydrates to simple sugar (eg, amylase breaks down starch to glucose).
Made in stomach, pancreas. Break down protein to amino acids.
Made in pancreas (works in small intestine). Break down lipids (fats) to glycerol and fatty acids.
Calculate the percentage loss/gain of mass in osmosis
% change if mass= 10((final mass - initial mass)/initial mass)
No energy required. Movement of particles in a solution or gas from a higher to a lower concentration, eg. O2 and CO2 in gas exchange, urea in kidneys. Factors that affect the rate are concentration, temperature and surface area.
No energy required, eg. Plants absorb water from the soil by osmosis through their root hair cells. Plants use water for several vital processes including photosynthesis and transporting minerals.