Ecology

Question 1

ecology

Answer 1

the study of relationships of living things with each other and with their physical environment

Question 2

biosphere

Answer 2

thin layer of life on the earth

Question 3

ecosystem

Answer 3

regions within the biosphere

made up of both living (biotic) and nonliving (abiotic) component

Question 4

community

Answer 4

the living part of an ecosystem

Question 5

population

Answer 5

all the members of a particular organism in a community

e.g. all the corals in a coral reef

Question 6

individual

Answer 6

a single organism

Question 7

producers

Answer 7

photosynthetic organisms

plants, photosynthetic bacteria, and algae

Question 8

consumers

Answer 8

eat producers or each other

protozoans and animals

Question 9

decomposers

Answer 9

break down dead producers and consumers

fungi and bacteria

Question 10

food chain

Answer 10

series of steps by which energy flows through an ecosystem
who eats who?
producer –> primary consumer (herbivore) –> secondary consumer (carnivore) –> tertiary consumer –> quaternary consumer

Question 11

food web

Answer 11

a group of interconnected food chains

the way it is in the real world

Question 12

trophic level

Answer 12

what level are you at in the food chain?
transfer of energy from level to level is insufficient (only ~10% gets passed on)
number of organisms decreases from level to level
there can only be a small number of high level consumers b/c it takes so many organisms in lower levels to support them
lots of producers, very little quaternary consumers

Question 13

ecological pyriamid

Answer 13

graphical representation of the concept of trophic levels

displays number of organisms or amount of energy at each level (decreases as you go up)

Question 14

bioaccumulation

Answer 14

fat-soluble toxins are not excreted well and so build up in the tissues more and more in higher tropic levels
top carnivores have the highest levels of all, they have accumulated toxin from all levels below them

Question 15

nutrient cycles

Answer 15

energy is the only thing that is put into an ecosystem

Question 16

carbon cycle

Answer 16

consumers produce CO2, producers use CO2

decomposers release C trapped in dead organisms back into the cycle as CO2

Question 17

nitrogen cycle

Answer 17

major component of the atmosphere
found in various biomolecules
soil bacteria convert nitrogenous waste products into forms that plants can use

Question 18

nitrogen fixation

Answer 18

some bacteria have the ability to convert atmospheric N2 into a form that is usable by plants

Question 19

terrestrial ecosystems (biomes)

Answer 19

temperature and rainfall influence the distribution
ecosystems occur in bands on distance from the equator (tundra is furthest north)
tropical rain forests-most productive and diverse
wetlands-areas of land covered by water, highly productive

Question 20

aquatic ecosystems

Answer 20

include fresh and salt water (marine)

coral reefs are most productive and diverse marine ecosystem

Question 21

littoral zone

Answer 21

where land and water come together

many organisms live there

Question 22

benthic zone

Answer 22

bottom

bottom-dwelling organisms

Question 23

pelagic zone

Answer 23

deep open ocean

few organisms live there

Question 24

symbiosis

Answer 24

2 organisms living together in some sort of relationship

Question 25

mutualism

Answer 25

both benefit

Question 26

commensalism

Answer 26

one benefits, one is not affected

Question 27

parasitism

Answer 27

one benefits, the other is harmed

Question 28

predator-prey

Answer 28

one feeds on another

Question 29

ecological niches

Answer 29

the role a particular organism plays in a community

its lifestyle

Question 30

keystone species

Answer 30

if removed from an ecosystem, has a significant negative impact on the remaining members

Question 31

natural selection

Answer 31

survival of the fittest
all organisms live under selection pressure-something that might kill you or make it less likely that you will reproduce
the organism that adapts best to or survives the selection pressures will be the most successful

Question 32

speciation

Answer 32

the development of new species

usually dues to natural selection

Question 33

species

Answer 33

a group of organisms that can breed with each other, but not members of any other group
new species arise from a previous species over a long period of time

Question 34

subspecies

Answer 34

geographically separated and different looking members of a species which can interbreed