6.3.2 Populations And Sustainability

Question 1

What is the population growth curve?

Answer 1

When the growth of a new population is graphed over time

Question 2

What is ohasem1

Answer 2

Slow growth phase - small numbers Of individuals are initially present and they reproduce, increasing population. Birth rate is slightly higher than death rate. Acclimatise to habitat

Question 3

What is phase 2

Answer 3

Rapid growth - few limits to their population growth. Number of breeding individuals increases rapidly and population exponentially rises.

Question 4

What is phase 3

Answer 4

Stable state - further growth is reverted by external factors. Population size fluctuates, but the sailed is normally the same. Birth rates are equal to death rates similarly.

Also known as carrying capacity - population reaches the maximum size that the environment can handle and it is not subject to succession

Question 5

What are the limiting factors of a population

Answer 5

Abiotic - non living factors that include temp, light, pH, water availability, humidity…

Biotic - living factors including predation, disease, competition

Question 6

How does migration affect population size?

Answer 6

Immigration - the movement of individual organisms into a particular area increases pop size.

Emigration - the movement of individuals away from an area, decreasing population size

Question 7

What are density independant factors?

Answer 7

Factors that have an effect on the whole population regardless of its size. These can dramatically change their population size. This includes earthquakes, fires, volcanic eruptions, storms. In some cases, these factors can remove whole populations of a species