20- organisms and their enviroments Flashcards Preview

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Flashcards in 20- organisms and their enviroments Deck (43)
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1

food chain

a diagram showing the flow of energy from one
organism to the next, beginning with a producer.

2

food web

a network of interconnected food chains.

3

main energy input and how is it transferred between organisms

sun, in a food chain by ingestion

4

trophic level

the position of an organism in a food chain, food
web, pyramid of numbers or biomass.

5

how is the energy lost in the enviroment

- respiration, movement
- animals dont eat the whole organism
- not all food molecules are digested or absorbed

6

producers

organisms that produce their own organic nutrients using energy from sunlight

7

herbivores

an animal that gets its energy from eating plants

8

carnivore

an animal that gets it energy by eating other animals

9

primary consumers

herbivores- feed on producers

10

decomposers

organisms that get their energy from dead waste or organism material; fungi, bacteria

11

interdependence

how the change in one population can affect others within the food web

12

why are food chains limited

because of inefficient loss of energy at each trophic level

13

pyramid of number

Diagram that represents the relationship between the number of organisms in each trophic level in food chain.

14

pyramid of biomass

it represents the dry mass of organisms at each trophic in the food chain

15

biomass

the total dry mass of a population.

16

the three processes that release CO2

respiration, combustion, decomposition

17

three places CO2 in stored

in living things, oceans, fossil fuels

18

the carbon cycle

1- Carbon is taken out of the atmosphere by photosynthesis
2-I t is passed on to animals and decomposers by feeding
3- it is returned by respiration; in plants, in animals and in decomposing microorganisms
**In addition, it is returned (in increasing amounts) by combustion of fossil fuels

19

nitrogen fixation

changing nitrogen into a reactive form

20

6 ways of nitrogen fixation

1- lightning 4- nitrifying bacteria
2- fertilizers 5- animal excretion
3- nitrogen fixing bacteria 6-denitrifying bacteria

21

lightning in nitrogen fixation

Allow nitrogen gas to combine with oxygen to form
nitrogen oxide, then dissolved in rain & washed into soil
to form nitrates.

22

fertilizers in nitrogen fixation

Ammonia is used to make ammonium compounds and
nitrates to be part of the fertilizers.

23

nitrogen fixing bacteria

They use nitrogen gas from air & combine it with other
substances to make ammonium ions, to fix nitrogen to make proteins.

24

nitrifying bacteria

Found in soil or in root nodules on plants as peas.
They use nitrogen gas from air & combine it with other
substances to make ammonium ions, to fix nitrogen to make proteins.

25

nitrogen

an element required to make protein

26

why cant plants and animals absorb nitrogen from the air

its a very stable gas, unreactive

27

animal excretion

By deamination, nitrogenous wastes [ammonia or urea] will be excreted from animals, then nitrifying bacteria turn it to nitrates.

28

deamination

removal of an amino group from a molecule

29

denitrifying bacteria

They turn nitrates & ammonia in soil to nitrogen gas into
atmosphere.

30

population

a group of organisms of one
species, living in the same area at the same
time.