topic 4: ecology

Question 1

photosynthesis

Answer 1

process by which cells synthesise organic molecules from inorganic molecules in the presence of sunlight

Question 2

detrivores

Answer 2

ingests non-living organic matter

Question 3

decomposition

Answer 3

when a compound is broken down, usually by heat to produce simpler molecules

Question 4

population

Answer 4

a group of the same species living in the same area at a given time

Question 5

ecosystem

Answer 5

interactions of the biotic and abiotic factors in a given area at a given time

Question 6

alternative hypothesis (h1)

Answer 6

there is a significant difference between the distribution of species (species are associated)

Question 7

consumers

Answer 7

ingest organic matter which is living or recently killed

Question 8

community

Answer 8

all the populations interacting in a given area at a given time

Question 9

flux

Answer 9

the process that moves an element from one reservoir sink to another

Question 10

saprotrophs (nutrient cycling)

Answer 10

breakdown organic nutrients to gain energy and in the process release nutrients back into inorganic molecules

Question 11

combustion

Answer 11

a process of burning which releases carbon dioxide from organic material such as fossil fuels or bio mass

Question 12

fossilisation

Answer 12

the process of an animal or plant becoming preserved in a hard petrified form

Question 13

carbon sink

Answer 13

anything that absorbs more carbon from the atmosphere than it releases

Question 14

habitat

Answer 14

the place where a living organism is found

Question 15

saprotrophs

Answer 15

feeds on non living organic matter by secreting digestive enzymes and absorbing the products

Question 16

extracellular digestion

Answer 16

excrete enzymes onto the food source. enzymes breakdown the food into simpler molecules that can be absorbed

Question 17

peat

Answer 17

partially digested organic matter that forms in acidic, water saturated soil. peat contains large amounts of carbon and can be compressed into coal after time

Question 18

species

Answer 18

a group of potentially interbreeding individuals that produce fertile offspring

Question 19

photoautotroph

Answer 19

makes organic compounds using energy derived from the sun

Question 20

chemoautotroph

Answer 20

makes organic compounds using energy derived from the oxidation of chemicals

Question 21

autotrophs (nutrient cycling)

Answer 21

convert nutrients from inorganic form into organic molecules

Question 22

null hypothesis (Ho)

Answer 22

there us no significant difference between the distribution of two species (distribution is random)

Question 23

heterotrophs (nutrient cycling)

Answer 23

ingest other organisms to gain organic forms of nutrients

Question 24

advantages of mesocosms experiments

Answer 24

1. scientists can control environmental conditions
2. ease of collection of data
3. many samples

Question 25

mesocosms

Answer 25

brings a small part of the natural environment under controlled conditions

Question 26

sustainable ecosystems

Answer 26

they require nutrient availability, energy availability and detoxification of waste products

Question 27

food web

Answer 27

a complex arrangement of interrelated food chains, showing the flow of energy between independent organisms

Question 28

respiration

Answer 28

the controlled release of energy from organic compounds to produce ATP

Question 29

food chain

Answer 29

sequence of who eats who in a biological community (ecosystem) to obtain nutrients

Question 30

limitations of mesocosm experiments

Answer 30

1. hard to copy natural environmental conditions
2. natural environments charge

Question 31

quadrats

Answer 31

used for an estimation of population of density and size and measuring distribution of species

Question 32

trophic level

Answer 32

organisms feeding position on a food chain

Question 33

autotrophs

Answer 33

organisms which synthesise organic molecules from inorganic sources

Question 34

heterotrophs

Answer 34

organisms which obtain organic molecules from other organisms