Definitions

Question 1

Abiotic Factors

Answer 1

Abiotic factors are non living variables that can influence where organisms can live. E.g. light intensity, temperature, soil pH, soil moisture.

Question 2

Biotic Factors

Answer 2

Biotic factors are interactions associated with living organisms. They can also influence the distribution of organisms in an ecosystem. E.g. competition for environmental recourses, grazing, predation, disease, food availability.

Question 3

Adaptation

Answer 3

The evolutionary process whereby an organism becomes better able to live in its habitat or habitats.

Question 4

Biodiversity

Answer 4

Where all different kinds of life are in one area.

Question 5

Biological oxygen demand

Answer 5

The amount of polluting material in a body of water can be determined by the biological oxygen demand.

Question 6

Biotic index

Answer 6

Biotic index is a scale for showing the quality of an environment by indicating the types and abundances of organisms present in a representative sample of the environment.

Question 7

Capture-mark-recapture

Answer 7

A technique used to estimate an animals population size.

Question 8

Density

Answer 8

Species density refers to the number of individuals of a species in an area.

Question 9

Dissolved oxygen concentration

Answer 9

The level of free, non-compound oxygen present in water or other liquids.

Question 10

Distribution

Answer 10

The general structure of the species population.

Question 11

Diversity Index

Answer 11

A quantitive measure that reflects how many different types of species there are in a community.

Question 12

Ecosystem

Answer 12

A community of interacting organisms.

Question 13

Ecosystem Diversity

Answer 13

Refers to the number of distinct ecosystems present in a defined area.

Question 14

Frequency

Answer 14

How common an allele is in a population.

Question 15

Genetic diversity

Answer 15

Relates to genetic variation of the number and frequency of alleles of a specific gene.

Question 16

Interquartile range

Answer 16

Spread of the middle 50% of the data values.

Question 17

Lincoln Index

Answer 17

Total population = No. of animals in 1st sample + total No. of second sample divided by number of marked species in the second samples.

Question 18

Percentage cover

Answer 18

To estimate the percentage cover of a species in a quadrat, count the number of squares that are more than half covered with the species.

Question 19

Quadrat

Answer 19

A frame used to isolate a standard unit of area.

Question 20

Qualitative data

Answer 20

Information about properties that are observed and generally cannot be measured numerically.

Question 21

Quantitative data

Answer 21

The use of math,statistical or computational techniques to measure living organisms.

Question 22

Random sampling

Answer 22

Used to select a sample that is unbiased.

Question 23

Relative abundance

Answer 23

Compares the similarity of the population size of each of the species present.

Question 24

Reliability

Answer 24

How many times you repeat an experiment.

Question 25

Simple random sampling

Answer 25

Organisms sampled randomly e.g. randomly thrown quadrat.

Question 26

Simpson biodiversity Index

Answer 26

A measure of the relationship between the number of different species in a habitat and the number of individuals within each species.

Question 27

Species

Answer 27

A living organism that can interbreed and produce fertile offspring.

Question 28

Species diversity

Answer 28

The 2 main factors taken into account when measuring species diversity are richness and abundance.

Question 29

Species richness

Answer 29

The more species present in a sample, the richer the sample.

Question 30

Standard deviation

Answer 30

A measure of data spread.

Question 31

Stratified random sampling

Answer 31

To devide a habitat into zones which appear different and take samples from each zone.

Question 32

Systematic random sampling

Answer 32

Selects a random starting point from the population, then a sample is taken from regular fixed intervals of the population depending on its size.

Question 33

Transect

Answer 33

A line across a habitat place where plants, animals and micro organisms live.

Question 34

Trent biotic index

Answer 34

The Trent biotic index is an index used to measure the quality of freshwater, based on the diversity and abundance of invertebrates present in a stream or river.

Question 35

Validity

Answer 35

Scientifically accurate information.