1- Populations

Question 0

Population

Answer 0

All organisms of 1 species

Question 1

Habitat

Answer 1

Place where organism lives

Question 2

Community

Answer 2

All the population of different species in a habitat

Question 3

Ecosystem

Answer 3

All organisms living (biotic) and all the non living (abiotic) in a particular area

Question 4

Abiotic conditions

Answer 4

Non living features of the ecosystem

Question 5

Biotic conditions

Answer 5

Living features of the ecosystem

Question 6

Niche

Answer 6

The role of species within its habitat
E.g
•what it eats
•when +where it feeds

Question 7

Adaptation

Answer 7

A feature a member of species have- increases chance of survival+reproduction

Question 8

3 adaptation

Answer 8

Physiological-processes inside body
Behavioural-way organisms act
Anatomical-structure features of the body

Question 9

Investigating pop. of organism

Answer 9

Look at abundance and distribution of species
•Abundance-number of individuals of 1 species in particular area - frequency
•Distribution- where particular species is within area

Question 10

Random sample

Answer 10

1.Choose area to sample- small area
2.random sample:
-divide field into grid
-use random number generator for random coordinates
3.Appropriate technique to sample pop
4. Repeat process - 10 or more - reliable estimate for whole area - more representative of pop.
•%cover estimated for whole area by average of all samples
•individuals of whole area - estimated by average data collected and multiply by size of whole area

Question 11

Measuring techniques

Answer 11

•Quadrat 
•Transects:
1.Line transact 
2.Belt transect
3.Interrupted transect

Question 12

Investigating animal pop

Mark release recapture- measure abundance of more mobile species

Answer 12

1. Capture sample of species- appropriate technique
2. Mark im harmless way- paint
3. Release back in habit
4. Wait- take 2nd sample of same pop.
5. count how many 2nd sample marked

Total pop size=
(1st sample ✖️2nd sample)
➗
marked in 2nd sample

Question 13

Accuracy of MRR

Answer 13

1. Marked sample enough time+opportunity to mix back in pop.
2. Marking hasn’t affected chances of survival
3. Changes in pop size are small during period of study (births,deaths,migration)
4. Large pop. sampled

Question 14

Variation in pop size

Answer 14

Abiotic factors - light,temp,water,space .etc
Temp right mammals conserve energy- growth and reproduction - increase pop.

Biotic factors
interspecific competition
compete for same resources- less resources - less growth an reproduction - decrease pop - less adapted species out-competed

Intraspecific comp
same species compete for same resources
Resources - growth an reproduction - size of pop. (Cycle)

Question 15

Variation in pop size (2)

Answer 15

Predation- predation kills+eats prey

Pop of predators+preys interlinked-pop. of 1 changes cause other pop. to change (cycle)

Question 16

Human pop.

Answer 16

BR- number of live births each year/1000 ppl in pop.
DR-number of deaths each year/ 1000 ppl in pop.

Pop growth rate= BR-DR
(⬆️or ⬇️pop)

Life expectancy- age person in pop. expected to live to - worked out by average age ppl die