Mitochondria, Chloroplasts, and Energy Production

Question 1

What is the endosymbiotic theory?

Answer 1

An evolutionary theory of the origin of eukaryotic cells from prokaryotic organisms

Question 2

What does the endosymbiotic theory state?

Answer 2

The organelles distinguishing eukaryote cells evolved through symbiosis of individual single-celled prokaryotes

Question 3

What is symbiosis?

Answer 3

Close and long-term biological interaction

Question 4

What are two pieces of evidence supporting the endosymbiotic theory?

Answer 4

• Binary fission of mitochondria and plastids
• Circular DNA inside some organelles, similar to bacteria

Question 5

Are the membranes of the mitochondria and chloroplasts part of the endomembrane system?

Answer 5

No

Question 6

What are the mitochondria and chloroplasts specialized to do?

Answer 6

Harness energy for the cell

Question 7

T or F: Mitochondria and chloroplasts are fully autonomous organelles.

Answer 7

False. They are semi-autonomous

Question 8

Can mitochondria and chloroplasts grow and multiply independently of other membrane-bound compartments?

Answer 8

Yes

Question 9

T or F: Mitochondria and chloroplasts contain their own circular genomes.

Answer 9

True

Question 10

What are mitochondria?

Answer 10

Specialized organelles that are the site of respiration in eukaryotic cells

Question 11

What serves as the universal energy currency of the cell?

Answer 11

ATP

Question 12

Which organelle oxidizes chemical compounds like sugars into carbon dioxide and transfers the chemical energy to ATP?

Answer 12

Mitochondria

Question 13

What shape is the mitochondria?

Answer 13

Rod-shaped

Question 14

Which layer of the mitochondrial membrane contains many enzymes with diverse metabolic function?

Answer 14

The outer mitochondrial membrane

Question 15

Which mitochondrial membrane contains porins?

Answer 15

The outer mitochondrial membrane

Question 16

What are porins?

Answer 16

Large channels permeable to many molecules when opened

Question 17

What are the folds in the inner mitochondrial membrane called?

Answer 17

Cristae

Question 18

What is the benefit of having cristae in the inner mitochondrial matrix?

Answer 18

They increase membrane surface area

Question 19

Which mitochondrial membrane contains machinery for aerobic respiration and ATP formation?

Answer 19

The inner mitochondrial membrane

Question 20

Which mitochondrial membrane is rich in cardiolipin?

Answer 20

The inner mitochondrial membrane

Question 21

Cardiolipin is a phospholipid characteristic of what?

Answer 21

Bacterial membranes

Question 22

What is cardiolipin needed for?

Answer 22

Needed for the optimal functioning of many enzymes

Question 23

What are the two aqueous compartments of the mitochondria?

Answer 23

The matrix and the intermembrane space

Question 24

What is contained within the mitochondrial matrix?

Answer 24

Mitochondrial ribosomes and DNA

Question 25

What is the intermembrane space?

Answer 25

The space between the inner and outer mitochondrial membranes

Question 26

What is cellular respiration?

Answer 26

A process that uses chemical energy stored in molecules (ex. carbohydrates and lipids) to produce ATP

Question 27

What is aerobic respiration?

Answer 27

Cellular respiration in the presence of oxygen

Question 28

What does aerobic respiration produce as a byproduct?

Answer 28

Carbon dioxide

Question 29

What are the three stages of substrate-level phosphorylation in animal cell cellular respiration?

Answer 29

- Glycolysis - Pyruvate oxidation - The citric acid cycle

Question 30

Which process produces only a small amount of the total ATP necessary for cellular functioning?

Answer 30

Substrate-level phosphorylation

Question 31

What does it mean for a coenzyme to be oxidized?

Answer 31

It's able to accept electrons

Question 32

What does it mean for a coenzyme to be reduced?

Answer 32

It's able to donate electrons

Question 33

What are the oxidized and reduced states of NAD?

Answer 33

- Oxidized: NAD+ - Reduced: NADH

Question 34

What are the oxidized and reduced states of FAD?

Answer 34

- Oxidized: FAD - Reduced: FADH2

Question 35

What does the oxidation of NADH and FADH2 allow for?

Answer 35

Allows electrons and energy to be transferred

Question 36

During cellular respiration in animal cells, what occurs after substrate-level phosphorylation?

Answer 36

Oxidative phosphorylation

Question 37

Which process produces the majority of ATP necessary for cellular functioning?

Answer 37

Oxidative phosphorylation

Question 38

What are the two main steps in oxidative phosphorylation?

Answer 38

- Generate electrochemical gradient - Synthesis ATP

Question 39

What is the electron transport chain (ETC)?

Answer 39

A series of intermediate electron carriers

Question 40

What is energy transfer at each complex along the ETC used for?

Answer 40

Used to pump H+ from the matrix into the intermembrane space and create an electrochemical gradient

Question 41

What occurs at the end of the ETC?

Answer 41

A low energy electron is transferred to the terminal electron acceptor, resulting in the production of H2O

Question 42

What is the final electron acceptor in the ETC?

Answer 42

Oxygen

Question 43

What is the enzyme after the ETC that synthesizes ATP?

Answer 43

ATP synthase

Question 44

What is the role of ATP synthase?

Answer 44

Synthesize ATP using proton movement down the electrochemical gradient

Question 45

What are chloroplasts?

Answer 45

Organelles that convert the energy of sunlight into chemical energy

Question 46

How do chloroplasts convert light energy into chemical energy?

Answer 46

By synthesizing simple sugars

Question 47

What type of organism contains chloroplasts?

Answer 47

Photosynthetic eukaryotes

Question 48

What is the third internal membrane of the chloroplast called?

Answer 48

The thylakoid

Question 49

Where is the site of the photosynthetic electron transport chain?

Answer 49

The thylakoid

Question 50

Where are light-collecting molecules contained within the chloroplasts?

Answer 50

The thylakoid

Question 51

T or F: The thylakoid is highly folded.

Answer 51

True

Question 52

What is chlorophyll?

Answer 52

The major photosynthetic pigment in the thylakoid

Question 53

What do enzymes do to the light energy collected by chlorophyll?

Answer 53

Use carbon dioxide as a carbon source to produce carbohydrates

Question 54

Why does chlorophyll appear green?

Answer 54

Because it is poor at absorbing green wavelengths

Question 55

What is photosynthesis?

Answer 55

The process of building carbohydrates using energy from sunlight and CO2

Question 56

What are the carbohydrates synthesized during photosynthesis used for?

Answer 56

- Used as a starting point for making other molecules - Used to synthesize ATP through cellular respiration

Question 57

What the two main stages of photosynthesis?

Answer 57

- Light-dependent reactions - Light-independent reactions/the calvin cycle

Question 58

Where do light-dependent reaction occur?

Answer 58

The thylakoid membrane

Question 59

What is produced from light-dependent reactions?

Answer 59

ATP and NADPH

Question 60

Does the electron movement through the photosynthetic ETC occur as part of light-dependent or light-independent reactions?

Answer 60

Light-dependent

Question 61

Where do light-independent reaction occur?

Answer 61

In the stroma of chloroplasts