4.1 Species, communities, and ecosystems

Question 1

Ecosystem definition

Answer 1

A community and its abiotic environment

Question 2

Habitat defintion

Answer 2

The environment in which a species normally lives, or the location of a living organism

Question 3

Species definition

Answer 3

A group of organism that can potentially interbreed and produce fertile offspring

Question 4

Population definition

Answer 4

A group of organism of the same species that live in the same area at the same time

Question 5

Community definition

Answer 5

A group of different (2+) populations living together and interacting in the same area

Question 6

Abiotic environment definition

Answer 6

non-living components of the environment (ex. sunlight, soil, water)

Question 7

what are the three methods of nutrition?

Answer 7

autotroph, heterotroph, mixotroph

Question 8

autotroph definition + role

Answer 8

organisms that synthesize its own organic molecules from inorganic sources
role: producer

Question 9

photoautotroph definition

Answer 9

organisms that synthesize organic molecules from energy derived from sunlight

Question 10

chemoautotroph definition

Answer 10

organisms that synthesize organic molecules from energy derived from the oxidation of chemicals

Question 11

heterotroph definition

Answer 11

organisms that obtain organic molecules from other organic organisms

Question 12

consumer definition

Answer 12

heterotrophs that obtain organic matter that is living or recently killed

Question 13

decomposer definition

Answer 13

organisms that consume dead organic matter (detritus) and recycle nutrients back to soil

Question 14

detritivore definition

Answer 14

heterotrophs that obtain organic matter from detritus by internal digestion

Question 15

saprotroph definition

Answer 15

heterotrophs that obtain organic matter from detritus by external digestion

Question 16

decomposer types

Answer 16

detrivore, saprotroph

Question 17

what does nutrient cycling enable?

Answer 17

The supply of inorganic nutrients

Question 18

why are ecosystems sustainable?

Answer 18

due to the recycling of nutrients and wastes & the continuous transfer of energy

Question 19

how is nutrient available?

Answer 19

decomposers help recycle inorganic nutrients

Question 20

how is energy available?

Answer 20

sunlight is the initial source of energy. Energy is transferred through the pyramid of energy.

Question 21

how are wastes removed?

Answer 21

Bacteria detoxify harmful wastes

Question 22

mesocosm definition

Answer 22

an enclosed environment that contains abiotic and biotic features of an ecosystem.

Question 23

role of a sealed glass vessel

Answer 23

• Prevent entry and exit of matter

- Light can enter

Question 24

chi squared test definition

Answer 24

a statistical test used to determine whether there is a significant association between two variables (species in ecology)

Question 25

role of quadrat sampling

Answer 25

to determine the population density in a habitat

Question 26

quadrat sampling method

Answer 26

• Quadrats are placed repeatedly in a sample area –> reliable estimate.
• number of quadrants regarding presence/absence, frequency, or %coverage of a given species can be recorded
• Systematic and random sampling when placing quadrats –> to avoid bias in the selection of samples.

Question 27

which organisms is quadrat sampling most suitable to?

Answer 27

plants and small, slow moving animals

Question 28

if the calculated chi squared value < value at 0.05 significance:

Answer 28

accept the null hypothesis (H0)

Question 29

if the calculated chi squared value > value at 0.05 significance:

Answer 29

accept the alternative hypothesis (H1)