Chapter 5 - Enzymes Flashcards
Define catalyst
a substance that affects the rate of a chemistry reaction and is not changed by the reaction
Are catalysts biological molecules?
yes
In living organisms, reactions are always happening.
a) what are they called?
b) what are most reactions controlled by?
a) metabolic reactions
b) enzymes
Why do us humans need enzymes?
because otherwise, reactions would happen too slowly for us to survive.
Can an enzyme work for many different nutrients?
no, different enzymes target different nutrients
a) Starch is digested into sugar (maltose) by…
b) Proteins are digested into amino acids by…
a) amylase
b) protease
Enzyme names often end in…
-ase
What two actions can enzymes perform?
1) break things down
2) build things up
Give an example of one enzyme that can digest the following nutrients
a) proteins
b) lipids
c) carbohydrates
a) pepsin / protease
b) lipase
c) Amylase / Sucrase
What two factors affect enzymes?
temperature and pH
Define optimal pH and optimal temperature
the pH / temperature at which the enzyme works fastest
Why do enzymes stop working after their optimum temperature or pH?
because the enzyme changes shape so the substrate no longer fits
At which pH does pepsin / protease work best?
pH 2
At which pH does amylase not work at all?
ph 2 (stomach acid - HCl)
What chemical does catalase break down and into what?
hydrogen peroxide → H₂O + O₂
