Lecture 26- Animal Adaptations II

Question 1

What are some mechanisms for animals to resist winter?

Answer 1

• Use specialized traits to survive extremes
• Increase insulation
• Acclimation (tolerance of cold temperature)
• Inactivity/Tolerance/Avoidance
• Hibernation or torpor (reduced metabolic activity)

Question 2

What is true hibernation?

Answer 2

Characterized by the extreme low temperature, slow heart rate, low metabolic rate

Question 3

What animals do true hibernation?

Answer 3

Warm blooded animals

Question 4

Why do cold blooded organisms not do true hibernation?

Answer 4

Because cold blooded organisms cannot control their body metabolic rates the same way as warm blooded organisms and rely on outside temperatures to regulate their body temperature

Question 5

For true hibernation, organisms rely on ____ and ____ wake up

Answer 5

• Finite food reserves acquired before hibernation period
• Wont wake up at all (deep sleep)

Question 6

What is brumation?

Answer 6

Hibernation like state of cold blooded organisms

Question 7

Can organisms in brumation wake up?

Answer 7

They can wake up to drink water

Question 8

What is torpor?

Answer 8

Light state of hibernation with reduced metabolic rate

Question 9

Can organisms in a state of torpor wake up?

Answer 9

They can wake up and eat or drink

Question 10

Describe hibernation of Arctic ground squirrels

Answer 10

Question 11

What is heterothermy?

Answer 11

Alternate between them controlling their body heat and letting the environment control their body heat (burning stored fat, not eating)

Question 12

What are some risks of hibernation?

Answer 12

• Cannot escape predation
• Can freeze if fat reserves are not high enough
• Availability of den sites
• Waking up too early

Question 13

Why do organisms hibernate?

Answer 13

• Save energy
• Avoid predation risk when food is scarce
• But can have high mortality during particularly hard winter

Question 14

Hibernation is most common among _____

Answer 14

Mid latitude mammals (30-50 degrees N)

Question 15

What are some examples of organisms that hibernate?

Answer 15

• Hoary marmot
• Arctic ground squirrel
• Meadow jumping mouse
• Woodchuck
• Western jumping mouse
• Least chipmunk
• Franklin ground squirrel

Question 16

____ come out of hibernation earlier because of _____

Answer 16

• Men
• Gonads/hormones

Question 17

____ body temperatures don’t dip as low as _____

Answer 17

• Torpor
• True hibernation

Question 18

What is daily torpor?

Answer 18

Rewarm during the day, really active during the day

Question 19

What are poikilotherms?

Answer 19

Cold blooded animals

Question 20

Poikilotherms have ____ over body temperature

Answer 20

No control

Question 21

What do cold blooded organisms do in winter?

Answer 21

• Hide for winter in dens or underground
• Fish enter a dormant state

Question 22

Those in brumation rely on what?

Answer 22

Rely on stores of glycogen

Question 23

What are some species of frogs that are freeze tolerant?

Answer 23

• Boreal chorus frog
• Wood frog

Question 24

As temperature drops ____ is dumped into the bloos stream

Answer 24

Glucose

Question 25

Glucose is a _______

Answer 25

Cryoprotectant

Question 26

Describe land hibernating frogs and freeze tolerance

Answer 26

• Frogs can become frozen
• Hide under leaf litter under the snow
• Contact with ice unavoidable
• Crystalization of body fluids
• Moist hibernation sites
• As temperature drops glucose is dumped into the blood stream
• Heart stops breathing and breathing ceases
• 65% of body water freezes
• Frog kept alive by anaerobic metabolism of energy stores
• Can survive to -8C
• Winters with little snow cover can cause them to die

Question 27

What can a fish do in winter conditions?

Answer 27

• Can migrate to warmer waters
• Enter a state of dormancy
• Production of antifreeze glycoproteins (AFGPs)

Question 28

What happens during dormancy in fish?

Answer 28

• Reduced metabolism
• Arrhythmic breathing