Ecosystems And Conservation Biology

Question 1

Ecosystem

Answer 1

Sun of all the organisms living in a given area and the abiotic factors that interact w/ biotic and abiotic components, defined by integration, and can vary greatly in spatial extent; two emergent processes: energy flows through ecosystems and chemicals cycle within ecosystems

Question 2

Primary production

Answer 2

Amount of light energy converted to chemical energy by autotrophs (per unit time); in a few ecosystems, chemoautotrophs are the primary producers

Question 3

Gross primary production (GPP)

Answer 3

Total primary production

Question 4

Net primary production (NPP)

Answer 4

Gross primary production minus energy used by autotrophs for cellular respiration (R); NPP=GPP-R

Question 5

What limits primary production?

Answer 5

In aquatic ecosystems: light and nutrients control primary production

In terrestrial ecosystems: moisture, temp., and nutrients control primary production

Question 6

You have 5 kg of eggs, 10 kg of flour, 10 kg of butter, and 10 kg of sugar. How many cakes can you make (when the recipe is 1 kg eggs, 10 kg flour, 1 kg butter, 1kg sugar)? What is the limiting ingredient?

Eggs

Flour

Butter

Sugar

Answer 6

Flour

Question 7

Trophic levels

Answer 7

Position an organism occupies in a good chain

Question 8

Autotroph

Answer 8

An organism that obtains organic food molecules w/o eating other organisms or substances derived from other organisms. Autotrophs use energy from the sun or from oxidation of inorganic substances to make organic molecules (i.e., primary producers)

Question 9

Heterotroph

Answer 9

An organism that obtains organic food molecules by eating other organisms or substances derived from them

Question 10

Decomposer

Answer 10

An organism that absorbs nutrients from no living organic material such as corpses, fallen plant material, and wastes, and converts them to inorganic forms (i.e., detritivores)

Question 11

Green food chain

Answer 11

Live maple leaves -> cricket -> robin -> Cooper’s hawk

Question 12

Brown food chain

Answer 12

Dead maple leaves -> bacteria, archaea -> earthworm -> robin -> Cooper’s hawk

Question 13

How much energy is transferred to each trophic level?

Answer 13

Only 10%

Question 14

What is cycle of energy across trophic levels?

Answer 14

Energy enters most ecosystems as sunlight, is converted to chemical energy by autotrophs, passed to heterotrophs as food, and dissipated as heat

Question 15

Top down control

Answer 15

A situation in which the abundance of organisms at each trophic level is controlled by the abundance of consumers at higher trophic levels; thus, predators limit herbivores, and herbivores limit plants

Question 16

Bottom up control

Answer 16

A situation in which the abundance of organisms at each trophic level is limited by nutrient supply or the availability of food at lower trophic levels; thus, the supply of nutrients controls plant numbers, which control herbivore numbers, which in turn control predator numbers

Question 17

Trophic cascade

Answer 17

Indirect interactions that can control entire ecosystems. Trophic cascades occur when predators limit the density and/or behavior their prey and thereby enhance survival of the next lower trophic level

Question 18

Biogeochemical cycles

Answer 18

Describe the flux of atoms and molecules between biotic and abiotic reservoirs

Question 19

Reservoir

Answer 19

Place where a type of atoms or molecules accumulate are held for a kind period of time

Question 20

Flux

Answer 20

Rate of movement between reservoirs

Question 21

What are the two characteristics that define the main reservoirs of elements?

Answer 21

-Whether they consist of organic or inorganic materials

-Whether these materials are available for direct use by organisms or unavailable

Question 22

What are the four major factors to consider in the cycling of water, carbon, nitrogen, and phosphorus?

Answer 22

1. Each chemical’s biological importance
2. Forms available to life
3. Reservoirs
4. Key processes driving movement of each chemical through its cycle

Question 23

Water cycle

Answer 23

-liquid water is the primary physical phase in which water is used

-reservoirs: oceans (97%), glaciers and polar ice caps (2%), and lakes, rivers, groundwater’s (1%)

-water moves by the processes of evaporation, transpiration, condensation, precipitation, and movement through surface and groundwater

Question 24

Carbon cycle

Answer 24

-photosynthetic organisms convert CO2 to organic molecules that are consumed by heterotrophs

-reservoirs: fossil fuels, soils and sediments, biomass, atmosphere, and sedimentary rocks

-CO2 is taken up and released through photosynthesis and respiration; additionally, volcanoes and the burning of fossil fuels contribute CO2 to the amosphere

Question 25

Nitrogen cycle

Answer 25

-N is a component of amino acids, proteins, and nucleus acids

-main reservoir: atmosphere (N2)

-atmospheric N2 must be converted to NH4+ or NO3- for uptake by planted via nitrogen fixation by bacteria

Question 26

Phosphorus cycle

Answer 26

-phosphorus is a major constituent of nuclei acids, phospholipids, and ATP

-phosphate is the most important inorganic form of phosphorus

-reservoirs: sedimentary rocks of marine origin, soil, oceans and organisms

-weathering of rocks releases phosphate into the soil, and it reaches aquatic systems through leaching

Question 27

For which biogeochemical cycle is photosynthesis important?

Carbon

Nitrogen

Phosphorus

Answer 27

Carbon

Question 28

What is the rate of decomposition controlled by?

Answer 28

Temperature, moisture, oxygen, and nutrient availability

Question 29

Cellular respiration (R)

Answer 29

The catabolic play heats of aerobic and anaerobic respiration, which break down organic molecules and use an electron transport chain for the production of ATP