Unit 1: Adaptations to Environmental Conditions

Question 1

[–] and [–] are important concepts for understanding adaptation

Answer 1

homeostasis and phenotypic plasticity

Question 2

Homeostasis

Answer 2

maintaining an internal environment within certain parameters (body temp, blood glucose…)

Question 3

Phenotypic Plasticity

Answer 3

phenotype expressed changes with conditions

Question 4

Most living cells prefere a [–] range of pH

Answer 4

narrow

Question 5

protein shape is sensitive to

Answer 5

[H+] or pH

Question 6

cellular mechanisms are [–]

Answer 6

temperature sensitive

Question 7

how do skunk cabbage plants grow in the winter?

Answer 7

they use the inefficiency of energy transfer in mitochondria to generate enough heat for growth in wintery conditions

Question 8

plant growth potential depends on

Answer 8

sunlight
water
availability of nutrients in the soil

Question 9

What are the horizons of soil?

Answer 9

O = dead organic litter (you will see this layer)
A = soil + decomposing organic material (“topsoil”)
E = soil without minerals (“subsoil”)

Question 10

topsoil

Answer 10

• soil combined with decomposed organic material
• provides minerals
• determines how well a plant can grow

Question 11

The surface area of soil particles can determine

Answer 11

how much water the soil can hold

Question 12

why does clay carry a lot of water

Answer 12

it has a charge and water is attracted to charged particles

Question 13

saturated soil

Answer 13

increase of water in the soil
too much water in the soil

Question 14

field capacity

Answer 14

how much water the soil can hold

Question 15

wilting point

Answer 15

too little water is held in the soil

Question 16

C3 plants store energy as

Answer 16

sugars through reactions in the mesophyll cells in their leaves

Question 17

where do plants exchange gases

Answer 17

the stoma

Question 18

mesophyll pathway

Answer 18

1. CO2 enters calvin cycle
2. CO2 + RuBP is converted to G3P
3. G3P exits cycle to become others sugars/can accumulate to become glucose or it is converted to RuBP (Rubisco)

Question 19

photosynthetic equation

Answer 19

6CO2 + 6H2O -> C6H12O6 + 6O2
carbon dioxide + water -> glucose + oxygen

Question 20

CAM adaptations

Answer 20

• change timing of photosynthesis
• Day = open stoma
• Night = close stoma -> process CO2
• found in terestrial plants

WHEN

Question 21

C4 adaptations

Answer 21

• take CO2 and store under hot + dry conditions as C4 mediary
• grabs CO2 and moves it deep inside leave
• found in terestrial plants
• more common in this latitude (as in PA)

WHERE

Question 22

Other adaptations in plants include changes in

Answer 22

morphology to defelct radiation or dissipate heat

Question 23

Animals use [–] to maintain optimal oxygen saturation and core body temperature

Answer 23

countercurrent exchange

Question 24

concurrent flow maximizes exchange at

Answer 24

50%

Question 25

countercurrent flow exchange is

Answer 25

• much higher compared to concurrent
• water is running past blood that is less saturatied to maximize exhange

Question 26

if body temp is < 37 degrees C

Answer 26

• body organs increase metabolism or increase shivering
• body temperature rises
• more energy turnover

Question 27

if body temperature > 37 degrees C

Answer 27

• sweating and panting begins
• body temperature falls
• reduces heat

Question 28

moisture harvesting lizards collect water on the body and transfer it to the mouth by

Answer 28

• the spikes allow water to collect and roll down to the head
• they then tilt their head back to drink the water

Question 29

convergent evolution

Answer 29

different species use same adaptation to a common problem

Question 30

thermal dormancy can occur under [–] temperatures

Answer 30

low or high temperatures

Question 32

Phenotypic trade-offs

Answer 32

small volume = greater heat loss = increased surface area
larger volume = less heat loss = decreased surface area

Question 33

Torpor

Answer 33

shut down body at colder temperatures to save energy

Question 34

Aestivation

Answer 34

hibernation during the summer

Question 35

hibernation

Answer 35

hibernation during the winter