BIOL 1108 Unit 2

Question 1

Dynamic equilibrium (Homeostasis)

Answer 1

Conditions vary around a central tendency but never a
constant condition; an acceptable range
rather than a point

Question 2

Regulators

Answer 2

Keep internal conditions fairly constant

Question 3

Regulator benefits

Answer 3

Wide range of habitats, enzymes work optimally

Question 4

Regulator costs

Answer 4

Takes lots of energy to maintain

Question 5

Conformers

Answer 5

Match internal environment to external environment

Question 6

Conformer benefits

Answer 6

Less energy, narrow range of habitats

Question 7

Conformer costs

Answer 7

Enzymes might not always act optimally, and limited
environmental range

Question 8

Thermoregulation

Answer 8

Temperature control can range from regulators to conformers; specific chemical reactions and enzyme functions can only occur at a specific temperature

Question 9

Endotherm

Answer 9

Temperature can be controlled by metabolism; can use any other method of thermoregulatory adaptation

Question 10

Ectotherm

Answer 10

Heat source is primarily from environment; cannot alter metabolic rate but can do everything else to help regulate temperature

Question 11

Homeotherm

Answer 11

Internal temperature is stable within a small range; includes all endotherms and some ectotherms

Question 12

Poikilotherm

Answer 12

Doesn’t need internal temperature to be consistent; majority of ectotherms

Question 13

Adaptations to regulate temperature if too hot (morphological, physiological, behavioral)

Answer 13

Sweat, vasodilation (dilation of blood vessels), panting, shedding, burrowing, heat dissipation through large ears, shade, swimming, light-colored skin, nocturnal

Question 14

Adaptations to regulate temperature if too cold (morphological, physiological, behavioral)

Answer 14

Blubber, hibernation, fur, shivering, vasoconstriction (constriction of blood vessels), goosebumps, limit blood flow to extremes

Question 15

Negative feedback cycle

Answer 15

Disturbances that promote changes that lead back towards equilibrium (rollercoaster of overshooting & undershooting)

Ex: Predator / Prey cycles

Question 16

Positive feedback

Answer 16

Disturbances that promote further change toward an extreme (Build, build, build, CRASH)

Ex: Hormones in labor, avalanche, climate change feedbacks

Question 17

First law of thermodynamics

Answer 17

Energy can be transferred and transformed, but NEVER destroyed

Question 18

Second law of thermodynamics

Answer 18

Every energy transfer or transformation increases entropy (disorder of energy)

Question 19

Optimal Foraging Theory

Answer 19

What will give an organism the most amount of energy for the least amount of time and energy spent

Question 20

Prey Switching

Answer 20

When an organism overconsumes its preffered prey and moves on to the next preferred

Otter prey items in order:
1 - Cancer Crabs
2 - Abalone
3 - Urchins
4 - Kelp Crabs

Question 21

Trophic Levels

Answer 21

Where an organism is in the food chain; how far it is energetically removed from photosynthesis

Question 22

Kelp -> Sea Urchin -> Otter dynamic

Answer 22

If one goes extinct, then the other will reproduce without regulation from predators, taking over the ecosystem and lowering biodiversity

Question 23

Top-down food web regulation

Answer 23

Predation by higher trophic levels affects the accumulation of biomass at lower trophic levels.

Ex: Kelp Forests

Question 24

Bottom-up food web regulation

Answer 24

Lower trophic level in food web affects the community structure of higher trophic levels by means of resource restriction

Ex: Sonoran Desert

Question 25

Trophic cascade

Answer 25

When predators limit the density / behavior of prey, enhancing survival of next lower trophic level. Ex: Urchin Barren

Question 26

Apex predator

Answer 26

Top predator that does not have anything that has it as prey Ex: Killer Whales

Question 27

Keystone species

Answer 27

Essential to an ecosystem relative to its population size Ex: In kelp forests = ALWAYS Sea Otters

Question 28

Kelp forest history

Answer 28

Pre-1800s otters, were being hunted for their fur, leading to urchin barrens, early 1900s, kelp forest locations were protected by law and were able to have kelp and sea otters reintroduced into the ecosystem to help it grow.

Question 29

Percentage of energy lost as energy moves up trophic levels

Answer 29

90%

Question 30

What moves through food webs

Answer 30

Energy, Carbon, Toxins, Pollutants, Biomass

Question 31

Bioaccumulation

Answer 31

Increasing toxicity with age / building up in an organism

Question 32

Biomagnification

Answer 32

Toxicity concentrations increase as you move up trophic levels (prey contains pollutants)

Question 33

Eutrophication

Answer 33

When an aquatic environment becomes enriched with nutrients (usually due to runoff), increasing the amount of plant and algae growth

Question 34

Eutrophication events order

Answer 34

1 - Runoff brings excess N & P into waterways 2 - Aquatic plants and algae grow 3 - Dissolved oxygen (dO2) increases 4 - Algae reach carrying capacity (K) as nutrient resources become limiting 5 - Algae die and decompose 6 - Oxygen is consumed, and dO2 drops 7 - Water becomes hypoxic or anoxic 8 - Animals move or die from lack of O2

Question 35

Why do smaller organisms loose more heat than larger ones?

Answer 35

The smaller an animal is, the higher the surface area-to-volume ratio

Question 36

Ocean Acidification

Answer 36

A reduction in pH of ocean, caused primarily by uptake of (CO2) from atmosphere

Question 37

Why is decreased pH bad?

Answer 37

Creates conditions that eat away at minerals used by oysters, clams, lobsters, shrimp, coral reefs, and other marine life to build their shells and skeletons.

Question 38

What month are greenhouse gases lowest?

Answer 38

September

Question 39

What month are greenhouse gases highest?

Answer 39

May

Question 40

January 2023 CO2 concentration

Answer 40

419ppm

Question 41

Water vapor feedback

Answer 41

Positive feedback loop that increases water vapor through an indirect increase in CO2 Increasing CO2 -> Global warming -> Increased water vapor

Question 42

Ocean CO2 feedback

Answer 42

Positive feedback loops that decrease the ability of the ocean to remove CO2 from the atmosphere with increasing temperatures; colder temperatures hold more dCO2 (kelp forests)

Question 43

Albedo feedback

Answer 43

Positive feedback loop that as there is less ice and it melts due to warming, albedo is dropping as well

Question 44

Methane-Permafrost feedback

Answer 44

Positive feedback loop that when permafrost melts with "ancient" methane it is released into the atmosphere; dangerous because methane has a very high Global Warming Potential (GWP)

Question 45

Carbon cycle

Answer 45

Way of reusing carbon atoms, which travel from atmosphere into organisms on Earth and back into atmosphere