Ch. 6 Cellular Respiration

Question 1

What is the limiting factor in athletic performance?

Answer 1

Aerobic capacity; ability of heart and lungs to deliver oxygen to body cells

Question 2

How do muscles obtain energy?

Answer 2

From sugar glucose through chemical reactions dependent on oxygen input

Question 3

Aerobic metabolism

Answer 3

Enough oxygen reaches cells to support energy needs

Question 4

Aerobic Capacity

Answer 4

Maximum rate that O2 can be taken in and used my muscle cells; most strenuous exercise body can maintain aerobically

Question 5

Anaerobic Metabolism

Answer 5

When the demand for oxygen exceeds ability for delivery and muscle cells switch to emergency mode; break down glucose inefficiently and produce lactic acid

Question 6

Plants/Autotrophs

Answer 6

Organisms that make organic matter from inorganic sources like CO2, water and minerals (photosynthesis)

Question 7

Heterotrophs

Answer 7

Cannot make organic molecules from inorganic ones and must eat the organic materiel to get nutrients

Question 8

Photosynthesis

Answer 8

Some energy from sunlight is captured in the chloroplast and atoms of carbon dioxide & water are rearranged to produce glucose & oxygen

Question 9

Cellular Respiration

Answer 9

A process that takes place in the mitochondria of eukaryotic cells where glucose is broken down to carbon dioxide and water and the cell captures some of the released energy to make ATP

Question 10

What is ATP?

Answer 10

Produced in the mitochondria and is a source of chemical energy that cells use for most of their work

Question 11

What type of process is cellular respiration?

Answer 11

Exergonic process that transfers energy from bonds in glucose to ATP

Question 12

How many ATP molecules are produced in cellular respiration?

Answer 12

Up to 32 ATP molecules from each glucose molecule

Question 13

How much energy does cellular respiration take from glucose?

Answer 13

Only 34% energy originally stored

Question 14

Kilocalorie

Answer 14

Quantity of heat required to raise the temp of 1 kilogram of water by 1 degree C

Question 15

Where is the energy necessary for life contained?

Answer 15

In the arrangement of electrons in chemical bonds of organic molecules

Question 16

What happens when the carbon-hydrogen bonds of glucose are broken?

Answer 16

Electrons are transferred to oxygen (strong tendency to attract electrons) and lose potential energy

Question 17

Redox Reaction

Answer 17

The movement of electrons from one molecule to another (oxidation, reduction)

Question 18

How do the atoms of glucose transform during cellular respiration?

Answer 18

Glucose loses hydrogen atoms and becomes oxidized to CO2

Question 19

How do the atoms of oxygen transform during cellular respiration?

Answer 19

Oxygen gains hydrogen atoms and becomes reduced to H2O

Question 20

NAD+

Answer 20

Important enzyme in oxidizing glucose that accepts electrons and becomes reduced to NADH

Question 21

Electron a Transport Chain

Answer 21

Electron carriers that act as a stairway for electrons

Question 22

What happens to electrons as they are transported down the electron transport chain?

Answer 22

ATP is generated

Question 23

What is the first stage of cellular respiration and where does it occur?

Answer 23

Glycolysis; occurs in cytoplasm

Question 24

What happens during glycolysis?

Answer 24

Breaks down glucose into two molecules of a three carbon compound called pyruvate

Question 25

What is required for the initial split of the glucose molecule?

Answer 25

An investment of 2 ATP molecules per glucose

Question 26

What happens after the splitting of glucose?

Answer 26

The 3 carbon molecules donate electrons to NAD+ and form NADH

Question 27

In glycolysis, what happens after NAD+ becomes NADH?

Answer 27

Enzymes transfer phosphate groups from fuel molecules to ADP and form two ATP molecules per molecule of glucose

Question 28

What remains of the fractured glucose at the end of glycolysis?

Answer 28

2 molecules of pyruvic acid; still holds most energy of glucose and is harvested in second stage

Question 29

What is necessary for the citric acid cycle to begin?

Answer 29

Each pyruvic acid must lose a carbon as CO2

Question 30

Acetic Acid

Answer 30

The remaining fuel molecules, each with only two carbon left

Question 31

What happens after acetic acid is formed?

Answer 31

Electrons are stripped from these molecules and transferred to another molecule of NAD+ to form NADH

Question 32

What happens after electrons are stripped from acetic acid?

Answer 32

Each acetic acid is attached to a molecule called coenzyme A (CoA) to from acetyl CoA

Question 33

General function of electron transport chain

Answer 33

collective group of electron “carriers” that function like NAD+ and form ATP as they move down the chain

Question 34

Where does glycolysis occur?

Answer 34

Cytoplasm

Question 35

What happens during glycolysis?

Answer 35

Glucose is broken into two 3 carbon molecules of pyruvate

Question 36

Lactic Acid Fermentation

Answer 36

NADH is oxidized to NAD+ and pyruvate is reduced to lactate

Question 37

Alcoholic Fermentation

Answer 37

NADH is oxidized to NAD+ and pyruvate is concerted to CO2 and ethanol