Energy

Question 1

What kind of consumers are prokaryotes?

Answer 1

heterotrophic, photosynthetic, and chemosynthetic

Question 2

What kind of consumers are protists?

Answer 2

heterotrophic and photosynthetic

Question 3

What kind of consumers are plants?

Answer 3

photosynthetic and heterotrophic

Question 4

What kind of consumers are fungi and animals?

Answer 4

exclusively heterotrophic

Question 5

What are the three sources of energy?

Answer 5

sunlight, oxidation of organic molecules, and oxidation of inorganic molecules

Question 6

Water use is ______ in CAM than in C3 and C4.

Answer 6

higher

Question 7

C4 has ______ water loss than C3 because…

Answer 7

less; it uses fewer stomata

Question 8

Which photosynthetic pathway do most plants use?

Answer 8

C3

Question 9

What is the first step in the C3 pathway?

Answer 9

Carbon fixation: CO2 combines with RuBp

Question 10

What enzyme catalyzes carbon fixation?

Answer 10

rubisco

Question 11

What is the product of carbon fixation?

Answer 11

PGA (three-carbon acid)

Question 12

What are some examples of plants that employ C3?

Answer 12

rice, wheat, and soybeans

Question 13

Where does C3 photosynthesis occur?

Answer 13

mesophyll cells ONLY

Question 14

Where do the reactions of C4 photosynthesis take place?

Answer 14

carbon fixation in mesophyll cells; calvin-benson cycle in bundle sheath cells

Question 15

What is the first step in C4 photosynthesis?

Answer 15

PEP carboxylase catalyzes the combination of CO2 and PEP to produce a C4 acid, which concentrates CO2

Question 16

Why do C4 plants open fewer stomata?

Answer 16

PEP carboxylase has a higher affinity for CO2 than rubisco, meaning they don’t have to work as hard to get CO2 to diffuse into the cells

Question 17

What happens after carbon fixation in C4 plants?

Answer 17

The C4 acid diffuses into the bundle sheath cell and breaks down to form CO2 and pyruvate. The CO2 then combines with RuBp to form PGA

Question 18

What kind of environments does C3 photosynthesis occur in?

Answer 18

moderate temp, moderate light, plentiful water

Question 19

What kind of environments does C4 photosynthesis occur in?

Answer 19

high temp, high light, limited water

Question 20

What kind of environments does CAM photosynthesis occur in?

Answer 20

high temp, low water

Question 21

How is the photosynthetic pathway broken up during CAM?

Answer 21

carbon fixation occurs at night and calvin-benson cycle occurs during the day

Question 22

Where does photosynthesis occur in CAM plants?

Answer 22

mesophyll cells ONLY

Question 23

What is photosynthetic active radiation?

Answer 23

400-700nm

Question 24

What changes the quantity and quality of light?

Answer 24

latitude, season, weather, time of day, landscapes, water quality, composition of organisms

Question 25

What are the most common elements in food?

Answer 25

carbon, nitrogen, phosphorous, hydrogen, oxygen

Question 26

What is the carbon-nitrogen ratio of plants? Are they nitrogen-rich?

Answer 26

25:1; no

Question 27

What is the carbon-nitrogen ratio of fungi? Are they nitrogen-rich?

Answer 27

10:1; no

Question 28

What is the carbon-nitrogen ratio of animals and bacteria? Are they nitrogen-rich?

Answer 28

5:1; yes

Question 29

How do we excrete excess carbon?

Answer 29

feces

Question 30

How do plants physically prevent being eaten?

Answer 30

bark, thorns, needles, etc.

Question 31

How do bark and needles protect trees?

Answer 31

They are very nitrogen-poor and, therefore, not nutritious

Question 32

______ tissues have more nitrogen.

Answer 32

Softer

Question 33

How do plants prevent being eaten?

Answer 33

toxic/secondary compounds and mechanical defenses

Question 34

How do animals prevent being eaten?

Answer 34

mobility, secondary compounds, mechanical defenses, camouflage, behavior

Question 35

What kind of animals have a type I functional response curve?

Answer 35

filter feeders

Question 36

What kind of animals have a type II functional response curve? Why does it look the way it does?

Answer 36

most animals; it takes time for them to acquire food

Question 37

What causes a type III functional response curve?

Answer 37

prey seeking refuge or predators switching prey type

Question 38

principle of allocation

Answer 38

limited energy has to balance demands of growth, reproduction, foraging, defenses, etc.

Question 39

What is the equation for rate of energy intake?

Answer 39

E/T (energy/time)

Question 40

Why do animals sometimes eat low reward items?

Answer 40

If they only ate high reward items and those items disappeared they would starve--they have to be flexible

Question 41

What are the assumptions of the optimal foraging theory?

Answer 41

animals want to maximize energy intake; cost of searching and handling time are constants