Lec 5 & Chp 5

Question 1

What is metabolism?

Answer 1

buildup & breakdown of nutrients within a cell
- provides energy
- sum of all chemical reactions that take place in an organism

Question 2

What is a catabolic reaction?

Answer 2

breaks down molecules; provides energy & building blocks for anabolism; EXERGONIC

Question 3

What is an anabolic reaction?

Answer 3

uses energy & building blocks to build complex molecules; ENDERGONIC

Question 4

What are metabolic pathways?

Answer 4

sequences of enzymatically catalyzed chemical reactions in a cell

Question 5

What is a catalyst?

Answer 5

substance that increases the rate of chem reaction

Question 6

What are enzymes?

Answer 6

proteins that act as biological catalysts

Question 7

How is ATP an intermediate between catabolism and anabolism?

Answer 7

the energy of catabolic reactions is used to drive anabolic reactions and the energy used for chemical reactions is stored in ATP.

Question 8

What is collision theory?

Answer 8

chemical reactions occur when atoms, ions, and molecules collide

Question 9

What is activation energy?

Answer 9

collision energy required for a chem reaction to occur

Question 10

What is reaction rate?

Answer 10

frequency of collisions containing enough energy to bring about a reaction

Question 11

What are some of the important enzymes and what do they do?

Answer 11

oxidoreductase - oxidation-reduction reactions
transferase - transfer functional groups
hydrolase- hydrolysis
isomerase - rearrangement of atoms
ligase - joining molecules; uses atp
apoenzyme - protein portion
holoenzye - apoenzyme + cofactor

Question 12

What factors influence enzyme activity?

Answer 12

temp
pH
substrate concentration
inhibitors

Question 13

What are competitive inhibitors?

Answer 13

fill the active site of an enzyme and compete w/ the substrate

Question 14

What are noncompetitive inhibitors?

Answer 14

interact w/ allosteric site rather than active site

Question 15

What are riboenzymes?

Answer 15

RNA that function as catalysts by binding to substrates and acting upon them

Question 16

What is oxidation?

Answer 16

removal of electrons

Question 17

What is reduction?

Answer 17

gain of electrons

Question 18

What is redox reaction?

Answer 18

oxidation reaction paired w/ reduction reaction

Question 19

Biological oxidations are often ____________.

Answer 19

dehydrogeneations

Question 20

Why is glucose such an important molecule for organisms?

Answer 20

compounds that have many hydrogen atoms are highly reduced compounds containing a large amount of potential energy

Question 21

How is ATP generated?

Answer 21

phosphorylation of ADP w/ the input of energy

Question 22

How are electrons transferred from one electron carrier to another?

Answer 22

electron transport chain (system)

Question 23

What are the 3 stages of carbohydrate catabolism?

Answer 23

glycolysis
krebs cycle
electron transport chain

Question 24

What is glycolysis?

Answer 24

oxidation of glucose to pyruvic acid; produces ATP & NADH

Question 25

What is chemiosmosis?

Answer 25

electrons pass down electron transport chain while protons are pumped across membrane

Question 26

What is fermentation?

Answer 26

releases energy from oxidation of organic molecules

Question 27

What are 4 different fermentations?

Answer 27

lactic acid fermentation: produes lactic acid
homolactic fermentation: produces lactic acid only
heterolactic fermentation: produces lactic acid and other compounds
alcohol fermentation: produes ethanol + CO2

Question 28

What are the 3 requirements for ATP production?

Answer 28

1. energy sources
2. electron carriers
3. final electron acceptors

Question 29

How do we classify organisms based on their primary energy source, and based on their carbon source? (4 names)

Answer 29

phototrophs - light as energy
chemotrophs - oxidation-reduction reactions of in/organic compounds
autotrophs - carbon dioxide
heterotrophs - require organic carbon source

Question 30

`What are the 4 different biosynthesis’?

Answer 30

polysaccharide
lipid
amino acid & protein
purine pyrimidine