conservation

Question 1

what is a population

Answer 1

a group of individuals of the same species that are interbreeding freely

Question 2

what are populations defined by

Answer 2

physical boundaries

Question 3

what is interspecific competition

Answer 3

the competition for resources between individuals of different species

Question 4

what is intraspecific competition

Answer 4

competition for resources between members of the same population/species

Question 5

what are the 3 important concepts of populations

Answer 5

populations have structure
they can expand and contract
they are regulated

Question 6

what is distribution shaped by

Answer 6

ecology of species

Question 7

what are the 3 types of distribution

Answer 7

regular/uniform
clumped
random

Question 8

what defines uniform distribution

Answer 8

the organisms are distributed in regular repeating patterns e.g. planted crops

Question 9

what defines clumped distribution

Answer 9

the organisms are found in clusters

the resources are also patchy protection form predation - lookout for predators is shared amongst the individuals

Question 10

what defines random distribution

Answer 10

no underlying resource or predation pattern

Question 11

is the density of organisms predictable

Answer 11

yes - from factors such as distribution of resources

Question 12

what does the logistic model of population growth show

Answer 12

that there is a threshold - either the environment or the population itself constrains the population

Question 13

what are the 2 ways that can force the population to level out

Answer 13

density dependent regulation - a function of the population itself
density independent regulation - environment constrains population

Question 14

what is a population

Answer 14

an association of populations occupying the same space - they can be any size and are defined by habitat boundaries

Question 15

species richness

Answer 15

the variety of species within a confined area

Question 16

.………. …………… varies with latitude (bigger latitude, nearer the equator) and altitude (height from sea level)

Answer 16

species richness
inc latitude - inc species
inc altitude - dec species

Question 17

what are human pressures on communities

Answer 17

1. Pollution
2. Habitat loss
3. Exploitation of populations
4. Species introductions

Question 18

what are the 2 types of pollution

Answer 18

toxic

nutrient enrichment

Question 19

what is toxic pollution

Answer 19

acts by poisoning
• Affects total number of organisms present
• may reduce number of species
• can cause total community loss

Question 20

what is nutrient enrichment pollution

Answer 20

e.g.
• sewage
• food processing waste
• farm silage effluent etc.

Question 21

what are the effects of habitat loss

Answer 21

• reduced community size
• fragmented populations
• prey populations reduced below threshold to support predators

Question 22

habitat fragmentation reduces the number of ………. ………..of the food chain

Answer 22

all levels

Question 23

what are the effects of overexploitation

Answer 23

major reduction in population e.g. overfishing

Question 24

what are the effects of introducing a new species

Answer 24

• compete with native species
• prey upon native species
• hybridise with native species – red deer and sika deer
• adjust habitats