Genetic Population And Ecosystems

Question 1

What is ecology

Answer 1

Scientific study of the interactions between organisms and their environment that determine their distribution and abundance

Question 2

What is a biosphere

Answer 2

Encompasses all living organisms found on earth together with th neon-living part of their environment
(Includes lands, ocean..)

Question 3

What are biomes

Answer 3

Regions of the world with similar climate, animals and plants

Question 4

What is interdependence

Answer 4

They way in which each species in a community depends on other species for things such as food, shelter, pollination, seed dispersal

Question 5

What is an Ecosytems

Answer 5

A community of organisms and the non-living components of their environment (biotic and abiotic)

Question 6

What is a population

Answer 6

Group of individuals of one species that occupy the same habitat at the same time and are potentially able to interbreed

Question 7

What is a community

Answer 7

All the populations of different species which interact together in the same habitat at the same time

Question 8

What is a habitat

Answer 8

Area in which an organism lives and that is characterised by physical condition a and other types of organisms present

Question 9

What is the carrying capacity and what does it depend on

Answer 9

An ecosystem supports a certain size of a population

• effect of abiotic factors
  -interactions between organsims- intra and interspecific competition and predation

Question 10

What is a niche

Answer 10

Describes how an organisms fits into its environment and refers to where an organism lives and what it does there

Includes the role of that an organism plays in the ecosystem and its biotic (living) and abiotic (non-living) interactions

Question 11

What is the competitive exclusion principle

Answer 11

Different organsims will have different niches within the same habitat
2 different species try to occupy the same niche, one will be out-competed by the other until one species survives
To increase their chances of survival, organsims will be adapted to their niches

Question 12

Give some example software limiting factors

Answer 12

Availability of food, light, watermelon oxygen, shelter
Accumulation of toxic waste, disease and predators

Question 13

What is interspecific competition

Answer 13

Competition for the same resources between organisms of different species within the same habitat or niche

Question 14

What is intraspecific competition

Answer 14

Competition between organisms of the same species for the same resources

Question 15

What is the effect of predator- prey relationships on population

Answer 15

Predator eat prey - reduce population size
With fewer prey available, the predators are in greater competition, the predator population is reduced and therefore fewer prey are eaten, so more survive and reproduce

Question 16

What is conservation

Answer 16

Management of the earths natural resources by humans in such a way that maximum use of them can be mad in the future

Question 17

What are the reasons for conservations

Answer 17

Personal - maintain our planet and our life-support system
Ethical
Economic -living organism contain a large pool of genes with the capacity to make many substances

Question 18

What is ecological succession

Answer 18

Directional change in the composition of species that occupy a given area through time- it involves initial colonisation and establishment of the plant pioneer species, followed by replacement of other species until relatively stable community is formed

Question 19

What is a climax community

Answer 19

Communities tend to remain stable over a long period of time

Question 20

Describe primary succession (5 marks )

Answer 20

1. Empty habitat in a harsh environment
2. Habitat colonised by pioneer plant species- modify environment creating conditions that support new species- making it less hostile by the formation of soil or organic matter and increase in nutrients
3. Enables other species to store colonise and survive changing the biodiversity as new plant species are established and various groups of animals enter the habitat
4. Organsims which are best adapted will out compete and replace those
5. Stability increases before reaching a climax community

Question 21

What are ways conservation cna be controlled

Answer 21

Grazing livestock
Controlled fires
Fishing quotas
Protecting land
Captive breeding
Seed bank

Question 22

What is sex linkage

Answer 22

Genes for certain characteristics are carried on the sex chromosomes

Question 23

What is autosomal linkage

Answer 23

If two or more genes are located on the same chromosome

Question 24

What is epistasis

Answer 24

When the allele of one gene affects or masks the expression of another allele in the phenotype