L6 Population Characteristics and Issues

flash cards

Define “Biotic potential”.

Biotic potential is the maximum rate at which a population can grow under ideal conditions, with no limiting factors (unlimited food, no predators, perfect habitat).

How is biotic potential related to the rate at which a population will grow?

The higher the biotic potential, the faster the population can grow.
Species with high biotic potential (like insects) reproduce quickly.
Species with low biotic potential (like elephants) grow slowly.

How do the concepts of birth rate and population growth differ?

• Birth rate: The number of births per 1,000 individuals per year.

• Population growth: The overall change in population size, determined by births + immigration − deaths − emigration.

Birth rate is only one part of population growth.

How does the age distribution of a population affect the rate at which a population grows?

If a population has many young individuals, it will grow faster because more people reach reproductive age.
If it has more older adults, growth slows down or may decline.

How does the sex ratio of a population affect the rate at which a population grows?

A population with more females grows faster because females produce offspring.
A population with fewer females grows slowly, even if the total population is large.

As the human population continues to increase, what might happen to other species?

Other species may:

• Lose habitat

• Experience decreased population sizes

• Become endangered or extinct

• Face competition for resources

• Be affected by pollution and climate change caused by humans

Human expansion often reduces biodiversity.

List 3 characteristics a population may have.

1. Size (number of individuals)

2. Density (how crowded it is)

3. Distribution (how individuals are spread out — clumped, uniform, random)

Explain asexual reproduction and sexual reproduction.

• Asexual reproduction:

  • One parent produces genetically identical offspring.

  • No fusion of sperm and egg.

  • Examples: bacteria dividing, plants sending out runners.

• Sexual reproduction:

  • Two parents produce genetically diverse offspring.

  • Involves sperm and egg.

  • Examples: humans, mammals, birds, most plants.