Chapter Nine

Question 1

Energy enters biological systems as ________ and eventually leaves as _____

Answer 1

sunlight, heat

Question 2

Matter is ________ with biological systems

Answer 2

recycled

Question 3

Photosynthesis uses ________ to convert _____ and ______ _______ into more complex molecules

Answer 3

sunlight, water and carbon dioxide

Question 4

Cellular respiration uses _______ molecules and _____ to create ATP

Answer 4

organic, oxygen

Question 5

ATP is used for ________ ____

Answer 5

cellular work

Question 6

Fermentation and cellular respiration are _______ (exergonic and spontaneous)

Answer 6

catabolic

Question 7

What is the equation for cellular respiration?

Answer 7

C6H12O6 + 6O2 –> 6CO2 + 6H2O + Energy (ATP + heat)

Question 8

Aerobic respiration ______ directly do work; intermediate ATP is used for work

Answer 8

doesn’t

Question 9

What is a redox reaction?

Answer 9

an oxidation-reduction reaction

Question 10

What is oxidation?

Answer 10

loss of electrons from one substance

Question 11

What is reduction?

Answer 11

addition of electrons to another substance

Question 12

Energy from a fuel ______ be harnessed efficiently if it is all released at once

Answer 12

cannot

Question 13

Energy breaks down in a _________ manner to avoid explosion

Answer 13

step-wise

Question 14

What happens in the electron tranport chain?

Answer 14

NADH passes its gained electron to the top of the chain that ends in oxygen –> there is a controlled fall of electrons to harness freed energy –> regenerates ATP

Question 15

What are the 3 main stages of cellular respiration?

Answer 15

• glycolysis
• pyrucate oxidation and citric acid cycle
• oxidative phosphorylation: electron transport and chemiosmosis

Question 16

What is the result of a redox reaction?

Answer 16

oxidative phosphorylation

Question 17

What is substrate-level phosphorylation?

Answer 17

when an enzyme transfers a phosphate group to ADP

Question 18

What is glycolysis?

Answer 18

glucose (sugar) broken into 2-3 carbon molecules; sugar splitting

Question 19

Glycolysis takes place ______ of mitochondria (cytosol); rest of respiration _______ mitochondria

Answer 19

outside, inside

Question 20

What is the product of glycolysis?

Answer 20

2 pyruvate, 2 ATP, 2 NADH

Question 21

In pyruvate oxidation, energy is changed to a __ ______ intermediate form before entering the _____ ______

Answer 21

2 carbon, Krebs cycle

Question 22

How many carbon dioxide molecules and NADH are released per pyruvate in pyruvate oxidation?

Answer 22

one

Question 23

What does the citric acid (Krebs cycle) do?

Answer 23

convert each carbon on the 2-carbon intermediate into carbon dioxide

Question 24

How many ATP are produced per pyruvate in the Krebs cycle?

Answer 24

one ATP

Question 25

How many NADH and FADH2 are produced per pyruvate in the Krebs cycle?

Answer 25

3 NADH and 2 FADH2

Question 26

Each glucose gets ____ full cycles

Answer 26

2; one for each pyruvate

Question 27

What happens in the electron transport chain for oxidative phosphorylation?

Answer 27

electron carrier (NADH and FADH2) pass electrons down a chain (lower energy at each level) eventually ending at oxygen

Question 28

What happens with the released energy in the electron transport chain?

Answer 28

released energy pumps hydrogen ions across inner mitochondrial membrane

Question 29

What is **chemiosmosis**?

Answer 29

an energy coupling mechanism

Question 30

What happens in chemiosmosis?

Answer 30

- hydrogen ions moce down concentratin gradient back across membrane via ATP synathse - catalyzes phosphorylation of ADP to ATP (attaches a phosphate group to ADP)

Question 31

What is the net ATP of glycolysis?

Answer 31

2 ATP

Question 32

What is the net ATP of the citric acid cycle?

Answer 32

2 ATP

Question 33

What is the net ATP of oxidative phosphorylation?

Answer 33

26-28 ATP

Question 34

What is the (total) net ATP of cellular respiration?

Answer 34

30-32 ATP

Question 35

What is the net energy of cellular respiration?

Answer 35

about 34% of total energy harvested from glucose oxidation | - would have been less if it occured all at once (rest lost as heat)

Question 36

What is **anaerobic respiration**?

Answer 36

the generation of ATP without oxygen

Question 37

__________ is sometimes considered a simple term of anaerobic respiration

Answer 37

Fermentation

Question 38

True anaerobic respiration uses a _________ molecule as the final electron acceptor in the electron transport chain

Answer 38

non-oxygen | - commonly a sulfate ion

Question 39

What is **fermentation**?

Answer 39

glycolysis and some way to regenerate NAD+

Question 40

What is the net ATP for each glucose molecule in fermentation?

Answer 40

2 ATP

Question 41

What are 2 common types of fermentation?

Answer 41

* **Alcohol**: produces carbon dioxide * **Lactic acid**: does not produce carbon dioxide - quick means of energy production when oxygen levels are low

Question 42

Glycolysis accepts a range of __________

Answer 42

carbohydrates

Question 43

__________ and __________ are broken into glucose and other simple sugars

Answer 43

disaccharides and polysaccharides

Question 44

________ are mainly used as a source of amino acids but can be used as a fuel

Answer 44

proteins

Question 45

Proteins are broken down into _____ _____, then convertedd to intermediates of ________ and the ________ cycle

Answer 45

amino acids, glycolysis, citric acid

Question 46

____ are broken down into glycerol and fatty acids

Answer 46

fats

Question 47

_______ is convervet to a glycolysis intermediate

Answer 47

glycerol

Question 48

_____ _____ are broken into 2-carbon sections that enter the citric acid cycle

Answer 48

fatty acids