topic 1 and topic 2

Question 1

define ecology

Answer 1

the study of the interactions between organisms and the environment in which they live.

Question 2

define ecosystems

Answer 2

community of interdependent organisms and the physical enviornment they interact with.

Question 3

biotic components

Answer 3

Producers→ the plants that convert energy into matter
Consumers→ animals that eat plants or other animals
Decomposers→ organisms that breakdown waste into component parts for reuse

Question 4

Temperature
Sunlight
pH
Salinity
Precipitation

Answer 4

abiotic components

Question 5

habitat

Answer 5

A habitat is the environment in which a species usually lives.

Question 6

define niche

Answer 6

The niche is the role an organism plays and the position it holds in the environment. It includes all the interactions the organism has with the abiotic and biotic environment.

Question 7

density-dependent factors

Answer 7

factors that affect the population only when it reaches a certain density. These include competition, disease, parasitism and predation (biotic factors most often)

Question 8

Density independent factors

Answer 8

factors that control population no matter what the density of it is. They include sunlight, temp, water, and natural disasters.

Question 9

Carrying capacity:

Answer 9

maximum number of individuals of a species that the enviornment can sustainably support in a given area.

Question 10

J-shaped population curve:

Answer 10

shows exponential population growth under ideal conditions with plenty of resources and limited competition.

Question 11

S-shaped population curve:

Answer 11

S-shaped curve is more likely when resources are limited-they are limited factors. Exponential growth is only possible for a short period of time. Population grows, resources are depleted and growth rate slows and eventually plateau’s.
→ likely to be accurate until the population approaches the carrying capacity.

Question 12

species

Answer 12

group of organisms with common characteristics that can interbreed to produce fertile offspring.

Question 13

Population

Answer 13

A population is a group of individuals of the same species living in the same area at the same time.

Question 14

population size is determined by:

Answer 14

Population size is determined by births and immigration (which increase the population) and by deaths and emigration (which decrease the population).”

Question 15

define community

Answer 15

A group of populations living and interacting with each other in a common habitat

Question 16

producers

Answer 16

Producers convert inorganic compounds into food.
Autototrophs (self-feeders)- they obtain food by making it for themselves.
Primary producers
Plants
Manily photosynthesis, small amount by chemosynthesis/

Question 17

Consumers

Answer 17

Reffered to as heterotrophs (other-feeders)
Herbivores eat just plans-leaves, flowers, fruits and nuts or stems, adn wood.
Omnivores eat both plants and other animals.
Carnivores eat only meat/other animals and these are the predators.

Question 18

Decomposers and detritivores:

Answer 18

“clean up crew” for ecosystems.
→ Obtain their energy and nutrients from dead plant and animal material and waste.
→ detritivores are the first stage of the decomposition cycle. E.g (millipedes, woodlice, worms and maggots)
Decomposers: decomposers such as bacteria and fungi absorb and metabolise waste and dead matter on a molecular level then release it as inorganic chemicals that can be recycled through the ecosystem via plan

Question 19

Photosynthesis

Answer 19

Carbon dioxide + water–> light chlorophyll–> glucose + oxygen

Question 20

Respiration

Answer 20

Glucose + oxygen–> Oxidation–> carbon dioxide + water + Energy

Question 21

bioaccumulation

Answer 21

the increase in the concentration of a pollutant in an organism as it absorbs or it ingests it from its environment

Question 22

Biomagnification:

Answer 22

the increase in the concentration of the pollutant as it moves up through the food chain,

Question 23

Biomass:

Answer 23

The mass of living organism in a given area expressed as dry weight of mass per unit of area of g m–2

Question 24

Productivity:

Answer 24

The conversion of energy into biomass in a given time expressed as. The rate of growth of plants and animals in the ecosystem. In business it is how much output you get from your input, usually measured annually.

Question 25

Gross:

Answer 25

It refers to the total amount of products made. In ecosystems that would be the total amount of biomass that is made and in business that could be the total amount of money made in a month or year.

Question 26

Net:

Answer 26

What is left over after losses. Ecosystem losses include respiration and fecal loss whilst business losses would be the cost of production (wages, taxes, bills, etc)

Question 27

Primary:

Answer 27

primary is to do with plants, secondary to do with animals.

Question 28

Primary productivity:

Answer 28

Primary productivity will be either gross or net and is usually measured for a whole trophic level.

Question 29

Gross primary productivity (GPP)

Answer 29

all the biomass produced by primary producers in a given amount of time (before any of it is used for respiration)

Question 30

Net primary productivity (NPP)

Answer 30

NPP represents the amount of usable biomass in an ecosystem; some used for growth, and some consumed by herbivores.

Question 31

equation for NPP

Answer 31

NPP= GPP - R

Question 32

Ecosystems are less productive:

Answer 32

At certain times of the year– cold seasons r less productive
At certain life cycle stages→ young organisms have higher growth rates
Hit by disease or pests
Fire damaged some of the standing crop

Question 32

Sustainable yield

Answer 32

the amount of biomass that can be extracted without reducing natural capital of the ecosystem.

Question 33

Gross secondary productivity (GSP)

Answer 33

GSP= food eaten - fecal loss

Question 33

Net secondary productivity (NSP)

Answer 33

What is left at the end of processes for animal growth

NSP= GSP - R