Unit 3: Enzymes and Digestion

Question 1

reaction rate

Answer 1

rate at which a reaction occurs

Question 2

enzyme

Answer 2

proteins that act as catalysts for reactions related to digestion

Question 3

catalyst

Answer 3

substance that speeds up the rate of a chemical reaction

Question 4

reactants

Answer 4

the substances that go into a reaction

Question 5

products

Answer 5

the substances that are created as a result of a reaction

Question 6

substrate

Answer 6

the substance that reacts with an enzyme

Question 7

active site

Answer 7

the spot on an enzyme that a substrate attaches to react

Question 8

enzyme-substrate complex

Answer 8

the connected enzyme and substrate during the reaction

Question 9

activation energy

Answer 9

the amount of energy required to start a reaction, needed for ALL reactions

Question 10

induced fit

Answer 10

enzymes are flexible and the active site can adjust to the substrate to optimize reactions

Question 11

competitive inhibitors

Answer 11

substances that bond to the active site of enzymes and slow reaction rates, can be removed by an enzyme competing for the ability to bond to enzyme

Question 12

noncompetitive inhibitors

Answer 12

substances that bond to the allosteric site of an enzyme, completely stop reactions for enzymes that they bond to

Question 13

denature

Answer 13

a protein’s inability to function due to environmental changes (ex: temperature, pH)

Question 14

allosteric site

Answer 14

the spot on an enzyme that a noncompetitive inhibitor attaches to

Question 15

salivary amylase

Answer 15

found in the mouth, helps digest carbohydrates

Question 16

lipase

Answer 16

helps digest fats, lingual lipase found in the mouth, pancreatic lipase made in the pancreas and active in the small intestine

Question 17

pepsin

Answer 17

found in stomach, helps digest proteins

Question 18

trypsin

Answer 18

made in pancreas, active in small intestine, helps digest proteins

Question 19

bile

Answer 19

produced in liver, stored in gallbladder, secreted into small intestine, composed of non-enzyme chemicals that aid breaking down fats into smaller pieces (mechanical digestion)

Question 20

peristalsis

Answer 20

the contraction and relaxation of muscles throughout the digestive system to keep food moving

Question 21

mouth

Answer 21

where initial digestion occurs, chemical-saliva, mechanical-teeth/chewing

Question 22

esophagus

Answer 22

connects mouth and stomach, food passes through but does not really digest here

Question 23

stomach

Answer 23

continues breaking down food, chemical-enzymes, mucus, acid; mechanical-churning, muscles; low pH/acidic

Question 24

small intestine

Answer 24

where most chemical digestion takes place, lots of enzymes, bile, very long and windy

Question 25

large intestine

Answer 25

whatever food remains is broken down by bacteria or turned into feces

Question 26

rectum

Answer 26

part of the large intestine where feces are stored

Question 27

liver

Answer 27

produces bile and a few enzymes, is not directly involved in digestion

Question 28

gallbladder

Answer 28

stores bile, releases it into small intestine, not directly involved in digestion

Question 29

pancreas

Answer 29

produces enzymes which are released into the small intestine, also produces hormones (ex insulin), not directly involved in digestion

Question 30

chemical digestion

Answer 30

chemical break down of molecules into different molecules or atoms

Question 31

mechanical digestion

Answer 31

physical break down of food

Question 32

substrate concentration

Answer 32

high concentration=slower reaction rate

Question 33

enzyme concentration

Answer 33

high concentration=faster reaction rate

Question 34

nonspecific inhibitors

Answer 34

temperature, pH

Question 35

specific inhibitors

Answer 35

competitive, noncompetitive

Question 36

endergonic

Answer 36

absorbs energy

Question 37

exergonic

Answer 37

releases energy

Question 38

primary structure

Answer 38

sequence of amino acids

Question 39

secondary structure

Answer 39

Hydrogen bonds between atoms in the backbones of amino acids, two types: alpha helix, beta pleated sheet

Question 40

tertiary structure

Answer 40

interactions (disulfide bridge, ionic bonds, hydrogen bonds, hydrophobic interactions) between R groups, how the alpha/betas fold into clumpy, spherical like shapes (instead of just long strands)

Question 41

quaternary structure

Answer 41

interactions (same types as secondary and tertiary) between multiple polypeptides, only applies to some proteins