Energy Flows & Ecosystems

Question 1

What is the Ecosphere? What parts make up the ecosphere?

Answer 1

The entire global ecosystem.

• lithosphere
• cryosphere
• hydrosphere
• atmosphere
• biosphere

Question 2

What is energy? Characteristics?

Answer 2

The capacity to do work measured in calories. It has no mass and doesn’t occupy space.

Question 3

What is potential energy?

Answer 3

Energy that is stored (ie, water stopped by a dam, gas sitting in a tank)

Question 4

What is kinetic energy?

Answer 4

Energy that has motion (ie, water being poured)

Question 5

What is low-quality energy?

Answer 5

Most energy available. It is dispersed at low temperatures and is difficult to gather. (ie, oceans)

Question 6

What is high-quality energy?

Answer 6

It is easy to use, but disperses quickly (ie, fire, coal, gas, nuclear - lots of energy is lost). This has low entropy, but as energy dispersed, entropy increases.

Question 7

What is the first law of thermodynamics?

Answer 7

Law of Conservation of Energy: energy is neither created nor destroyed only transferred between forms

Question 8

What is the second law of thermodynamics?

Answer 8

Law of Entropy: When energy is transformed, there is always a decrease in the amount of usable energy (heat loss).

Question 9

What is entropy?

Answer 9

The measure of disorder/randomness of a system. More energy dispersed, higher the entropy.

Question 10

What is the proportional break down of where the sun’s energy goes?

Answer 10

• 33% reflected back (off of ice sheets, etc)
• 42% heats the earth’s surface
• 23% evaporates water
• > 1% forms the basis of ecosystems

Question 11

What is the path of photosynthesis?

Answer 11

CO2 + H2O + energy = O2 + C6H12O6 (sugars - glucose, cellulose, starches, etc)

Question 12

Define autotroph. What is another name for it? Name the types.

Answer 12

It captures energy and converts it to matter (self-feeders). AKA producers. Phototrophs & chemoautotrophs

Question 13

Define heterotroph. What is another name for it?

Answer 13

It gets energy through eating other organisms. AKA consumers

Question 14

Define phototrophs

Answer 14

They obtain energy from light, where the majority of energy is lost in the process, but biomass is still produced …. PLANTS

Question 15

Define biomass

Answer 15

The sum of all living material

Question 16

Define chemoautotrophs

Answer 16

They gain energy from chemicals in the environment though chemotaxis. They are just as important as phototrophs as they are fundamental in biogeochemical cycles… BACTERIA

Question 17

What is a food chain?

Answer 17

An energy pathway.

Question 18

Describe a food chain

Answer 18

Herbivores (primary consumers) eat producers, which gets passed to carnivores (secondary/tertiary consumers), and then decomposers (detritivores) feed on all dead organisms.

Question 19

What is a trophic level?

Answer 19

Each food chain level

Question 20

Describe possible omnivore food chains

Answer 20

1. eat veggies - primary consumers
2. eat beef - secondary consumers
3. eat certain fish - tertiary consumers

Question 21

Describe decomposer food chains

Answer 21

detritus (dead organic matter) is high in potential energy, but only decomposers can eat it. They break down materials into simpler compounds/elements (ie, CO2, H2O)

Question 22

What is a food web?

Answer 22

A complex mix of food chains

Question 23

What is cellular respiration?

Answer 23

Metabolic processes (essentially opposite of photosynthesis) to break down carbs and release energy for variety of uses in the body

Question 24

What happens in biotic pyramids?

Answer 24

As you move through trophic levels, more energy is lost (low energy efficiency), so top of food chain species (apex predators) are very vulnerable to lower level changes. Example, beef requires lots of energy, so vegetarian is more efficient.

Question 25

Define productivity

Answer 25

the rate at which energy is transformed into biomass

Question 26

What is Gross Primary Product (GPP)?

Answer 26

the rate of biomass production (total energy production)

Question 27

What is Net Primary Productivity (NPP)?

Answer 27

Calculated by GPP minus cellular respiration (R), it is the amount of energy available to heterotrophs

Question 28

What is Net Community Productivity (NCP)?

Answer 28

It is the primary productivity minus autotrophic and heterotrophic respiration

Question 29

What is a specialist species?

Answer 29

They have narrow niches (very specific conditions - food, habitat, climate) required for survival. More susceptible to population fluctuation because of environmental change. Often endangered species. Ex, panda

Question 30

What is a generalist species?

Answer 30

They have broad niches (can live in a variety of conditions) and are very adaptable to location & food. Ex. black bear

Question 31

What is parasitism?

Answer 31

When a predator lives on or in it’s prey, and only the predator receives the benefits in the relationship. The predator will receive nourishment and can lead to the death of the host. ex, tapeworms

Question 32

What is mutualism?

Answer 32

This relationship benefits both species. ex, pollinator and flowers

Question 33

What is commensalism?

Answer 33

A relationship that benefits one species, but does not harm the other. ex, vines growing up a tree

Question 34

What is a keystone species?

Answer 34

It strongly influences a community, and often play a large role in maintaining the ecosystem they live in. This species often impacts other species in the ecosystem. Ex, beaver controlling water level through it’s dam