LEC EXAM #2 CHP. 8

Question 1

Exergonic reaction:

Answer 1

Releases energy

Reactants > products

Question 2

Autotroph:

Answer 2

Makes its own food from inorganic source

Question 3

Heterotroph:

Answer 3

Gets food from organic material

Question 4

Chemoautotroph:

Answer 4

Makes its own food from a chemical source

Question 5

LEO goes GER:

Answer 5

Loss of electrons: oxidation

Gain of electrons: reduction

Question 6

Electron carriers:

Answer 6

NAD+/NADH and FAD/FADH2

Question 7

Metabolism is made up of:

Answer 7

Anabolism: building up
Catabolism: breaking down

Question 8

Why does ATP have a lot of energy associated with it?

Answer 8

Has 3 phosphates next to each other that have a negative charge (repelling each other) -> breaking off a phosphate releases some energy (exergonic rx)

Question 9

Release of phosphate from ATP causes:

Answer 9

Coupling of energonic reactions (reactions that require energy)

Question 10

Enzymes/biological catalysts make the energy of activation hill:

Answer 10

SMALLER and makes it more likely that the reaction will make place

Question 11

Product formation:

Answer 11

Does NOT form faster with the enzyme

Question 12

Rate of the reaction with or without the enzyme:

Answer 12

Stays the same, the enzyme just makes it more likely that the reaction will occur

Question 13

Energonic reaction:

Answer 13

Requires energy

Products > reactants

Question 14

Apoenzyme:

Holoenzyme:

Answer 14

• Not active until it binds a coenzyme (vitamin) or cofactor (inorganic ion)
• Has cofactor and coenzyme

Question 15

Cofactor:
Coenzyme:

Answer 15

Inorganic ion

Vitamin

Question 16

Enzyme:

Answer 16

• comes from proteins
• lower activation energy
• works like a lock and key
• only binds a specific substrate
• biological catalyst

Question 17

Substrate:

Answer 17

• Molecule that enzyme acts on

- Fits into an a specific shape of the active site of an enzyme

Question 18

Process of enzyme reaction:

Answer 18

1. Substrate enters active site of enzyme
2. Enzyme/substrate complex forms
3. Substrate is converted to products (cofactor or coenzymes)
4. Products leave the enzyme

Question 19

Allosteric site:

Answer 19

Other site that causes confirmation change

Question 20

Non-competitive inhibiton:

Answer 20

Doesn’t directly compete for active site-> binds to allosteric site instead-> causes confirmation change that doesn’t allow you to bind substrate (turns off enzyme)

Question 21

2 ways to turn off an enzyme:

Answer 21

• Competitive inhibition
• Noncompetitive inhibition
• Cofactors or coenzymes not being present

Question 22

Allosteric activators:

Answer 22

Activates the enzyme/changes the shape so the substrate can bind again

Question 23

Allosteric inhibitors:

Answer 23

Binds to enzyme to make it inactive

Question 24

Feedback inhibition:

Answer 24

The final product of the metabolic pathway that inhibits the pathway by preventing the enzyme from converting the product

Question 25

True or false: Prokaryotic and eukaryotic cells both perform glycolysis in the cytoplasm:

Answer 25

True

Question 26

Enzymes come from:

Answer 26

Proteins that come from genes

Question 27

Gene:

Answer 27

Piece of DNA that codes for a protein

Question 28

How do you control whether a competitive inhibitor binds or doesn't bind to the active site?

Answer 28

Decreasing the inhibitors or substrate

Question 29

Every cell does:

Answer 29

Glycolysis -Bacteria, prokaryotic, eukaryotic, e.coli

Question 30

Noncompetitive inhibition vs. feedback inhibition:

Answer 30

Product MUST be the noncompetitive inhibitor in feedback inhibition but in noncompetitive inhibition, the inhibitor doesn't have to be the product

Question 31

Glucose has:

Answer 31

6 carbons-> breaks down into 2, 3 carbon molecules

Question 32

How many pyruvate can I make from 1 glucose molecule?

Answer 32

2 pyruvate

Question 33

Investment phase of glycolysis:

Answer 33

Process of converting glucose into glyceraldehyde 3-phosphate -2 ATP-> 2 ADP (costs us 2 ATP)

Question 34

Pay off phase of glycolysis:

Answer 34

-Process of making 2, 3 carbon pyruvate from glyceraladehyde 3-phosphate NAD+-> NADH 2 ADP-> 2ATP

Question 35

Pyruvate can do what in eukaryotic cells?

Answer 35

Cross the mitochondrial membrane

Question 36

What cannot cross the mitochondrial membrane?

Answer 36

Glyceraldehyde 3-phophate

Question 37

What do we get back from the pay off phase of glycolysis?

Answer 37

NAD+-> NADH: electron carriers that have energy associated with it 2ADP-> 2ATP: excess energy

Question 38

Aceytl-coA=

Answer 38

2 carbons each

Question 39

In Krebs, for every acetyl-coA, we get:

Answer 39

3 NADH 1 FADH2 1 ATP

Question 40

4 oxaloacetate + 2 acetyl-coA=

Answer 40

6 carbon= citrate

Question 41

Oxaloacetate:

Answer 41

4 carbon

Question 42

Goal of Krebs:

Answer 42

To make electron carriers (NAD+/NADH) and to send them to the ETC

Question 43

Aerobic prokaryotic cells in glycolysis:

Answer 43

- With oxygen | - Same steps take place but happens in the cytoplasm

Question 44

Eukaryotes:

Answer 44

Always in mitochondria

Question 45

Prokaryotes:

Answer 45

Always in cytoplasm and doesn't cross mitochondrial membrane

Question 46

Inner membrane of mitochondria: | Outer membrane of mitochondria:

Answer 46

Matrix | Inner membrane space

Question 47

ETC:

Answer 47

Series of electron carrying proteins

Question 48

As NADH-> NAD+ and drops off an electron into the matrix:

Answer 48

It pumps out a proton into the inner membrane space

Question 49

Result of protons in the inner membrane space:

Answer 49

3H+ in inner membrane space

Question 50

Last pump:

Answer 50

Gives electron to oxygen to make water

Question 51

Oxygen in the ETC is:

Answer 51

Last electron accepter

Question 52

ATP synthase:

Answer 52

Tunnel protons go through in the ETC

Question 53

How is ATP made in the ETC?

Answer 53

Uses the energy of the protons in the inner membrane space to go down their concentration gradient through ATP synthase to take ADP + an inorganic phosphate to make ATP

Question 54

IN THE ETC: FADH2 yields: NADH yields:

Answer 54

2 ATP | 3 ATP

Question 55

Why does FADH2 give you less ATP?

Answer 55

Because it's dropping off it's electron at the 2nd pump

Question 56

NADH-> NAD+ drops off it's electron at:

Answer 56

First pump

Question 57

In aerobic prokaryote:

Answer 57

ETC happens in the plasma membrane

Question 58

In aerobic prokaryotes, protons are pumped:

Answer 58

Outside the cell into plasma membrane-> protons come down ATP synthase into the cytoplasm

Question 59

Anaerobic prokaryotes:

Answer 59

Can still perform ETC but do NOT have oxygen as their last electron carrier

Question 60

If no O2 is present:

Answer 60

- Won't be able to regenerate NAD+ | - Fermentation occurs

Question 61

Goal of fermentation:

Answer 61

-To take NADH-> NAD+ so that you can continue to do glycolysis-> NET 2 ATP

Question 62

How do humans make ATP anaerobically?

Answer 62

Pyruvate-> (NADH->NAD+)-> lactic acid-> 2 ATP

Question 63

Yeast makes: Humans make: Goal?

Answer 63

Ethanol Lactic acid To make NAD+ to continue to run glycolysis to yield 2 ATP

Question 64

Competitive inhibitor:

Answer 64

Competing for the active site

Question 65

Krebs occurs where for? Prokaryotes: Eukaryotes:

Answer 65

Cytoplasm | Mitochondria