System Earth Ch 09

Question 1

What are the 4 fundamental characteristics of life?

Answer 1

it spreads exponentially
it needs energy
it pollutes
it’s versatile in its interactions

Question 2

autotrophs

Answer 2

create their own energy, usually through photosynthesis

Question 3

heterotrophs

Answer 3

require organic matter to grow

Question 4

the two autotrophic pathways

Answer 4

photosynthesis and chemosynthesis

Question 5

three heterotrophic pathways

Answer 5

aerobic respiration, anaerobic respiration, and fermentation

Question 6

methanogens

Answer 6

can be either autotrophic or heterotrophic
produce methane through their metabolism
very important for biogeochemical cycling

Question 7

what is the net effect of all theses chemical reactions and their interactions?

Answer 7

an unstable, highly reactive, far-from-chemical-equilibrium atmosphere that is a signature of life on our planet

Question 8

population

Answer 8

all members of a single species that live in an area

Question 9

community

Answer 9

two or more groups of interacting species in an area

Question 10

biome

Answer 10

a region with a characteristic plant community

Question 11

ecosystem

Answer 11

a community of species and the physical envrionment that supports it

Question 12

C4 vs C3 plants

Answer 12

C4 - higher optimum temperature (and way higher photosynthetic rate at optimum). reaches max efficiency at lower CO2 ppm

Question 13

ecotone

Answer 13

a place where one ecosystem gradually merges into another.

Question 14

exploitation efficiency

Answer 14

how many units of carbon are used at each stage of the foodweb.

Question 15

succession

Answer 15

the reestablishment of an ecosystem after a natural of human disturbance.
It shows an ecosystem has a capacity to heal.

Question 16

biodiversity as part of the Earth’s health

Answer 16

the capacity to cope with large changes is enhanced by biodiveristy - hence the Earth’s help can be measured through biodiversity.

Question 17

Simpson’s index.

Answer 17

a measure of how likely to individuals drawn from the same population will be from the same species.

Question 18

why are tropics so diverse?

Answer 18

even through the ice ages, their climate has been relatively stable. As such, their ecosystems has had the time to evolve.

Question 19

intermediate disturbance hypothesis

Answer 19

small disturbances allow for speciation and increase biodiversity

Question 20

diversity of interactions

Answer 20

the types of different interactions between organisms. - 500 species of ants vs 500 species has a different diversity of interactions.