Biol4 section 1 definitions

Definitions from first part of unit 4 biology at GCE level

HideShow resource information
Abiotic
Non-living (components include temperature and rainfall).
1 of 22
Biotic
Living (components include competition and predation).
2 of 22
Biosphere
Life supporting layer of land, air and water that surrounds the Earth.
3 of 22
Ecosystem
More or less self-contained functional units made up of all the interacting BIOTIC and ABIOTIC factors in a specific area.
4 of 22
Population
A group of individuals of the same species that occupy the same habitat at the same time.
5 of 22
Community
All the populations of different organisms living and interacting in a particular place at the same time.
6 of 22
Habitat
The place where an organism usually lives, which is characterised by physical conditions and the species of other organisms present.
7 of 22
Micorhabitats
A smaller unit within a habitat with its own microclimate.
8 of 22
Ecological Niche
All conditions and resources required for an organism to survive, reproduce and maintain a viable population. Where an organism lives and what it does there.
9 of 22
Abundance
The number of individuals of a species in a given space.
10 of 22
Random sampling
A method used to avoid bias in collecting data. Quadrats and randomly generated numbers are used.
11 of 22
Systematic Sampling along transects
Used to measure the abundance and distribution of a species in a non random manner. Particularly important where some form of transition in the communities of plants and animals takes place.
12 of 22
Frequency
The likelihood of a particular species occurring in a quadrat. Gives quick idea of species present and their general distribution within the area. Doesn't provide info on density and detailed distribution of a species.
13 of 22
Percentage Cover
An estimate of the area within a quadrat that a particular plant species covers. Useful where a species is particularly abundant or is difficult to count. Less useful where organisms occur in many overlapping layers. Quick and easy to do.
14 of 22
Mark-release-recapture techniques
Known no. of animals caught, marked in some way (marking pens, tags), and then released back into community. Some time later, a given no. of individuals is collected and no. of marked individuals is recorded.
15 of 22
Population Size
No. of individuals in a population.
16 of 22
Limiting Factor
A variable that limits the rate of a chemical reaction.
17 of 22
Intraspecific Competition
Competition between members of the same species for resources such as food, water, breeding sites etc.
18 of 22
Interspecific Competition
Competition between member of different species for resources such as food, light, water etc. Where populations of 2 species occupy the same niche, one usually has a competitive advantage.
19 of 22
Predator
An organism that feeds on another organism.
20 of 22
Prey
An organism that is fed upon by another organism.
21 of 22
Selection Pressure
The environmental force altering the frequency of alleles in a population.
22 of 22

Other cards in this set

Card 2

Front

Living (components include competition and predation).

Back

Biotic

Card 3

Front

Life supporting layer of land, air and water that surrounds the Earth.

Back

Preview of the back of card 3

Card 4

Front

More or less self-contained functional units made up of all the interacting BIOTIC and ABIOTIC factors in a specific area.

Back

Preview of the back of card 4

Card 5

Front

A group of individuals of the same species that occupy the same habitat at the same time.

Back

Preview of the back of card 5
View more cards

Comments

No comments have yet been made

Similar Biology resources:

See all Biology resources »See all 1 Populations resources »