Population Dynamics and Ecosystem Interactions in Biology

The video tutorial by Miss Esterick covers Topic 7 of A-Level Biology, focusing on populations, abiotic and biotic factors. It defines key terms such as population, habitat, and niche, and explains how abiotic factors like temperature and light affect ecosystems. The video also discusses biotic factors, including competition and predator-prey relationships, highlighting how these interactions influence population sizes and dynamics.

What is the definition of a population in ecological terms?

• A group of organisms of the same species living in the same area at the same time.

• The non-living components of an ecosystem.

• A group of different species living in the same area.

• The role of an organism within its ecosystem.

What is the role of a niche in an ecosystem?

• It is the physical space an organism occupies.

• It is the role and position an organism has within its ecosystem.

• It is the total number of species in an ecosystem.

• It is the non-living components of an ecosystem.

What is carrying capacity?

• The average population size over time.

• The minimum population size required for survival.

• The maximum population size an ecosystem can support.

• The maximum number of species an ecosystem can support.

Which of the following is NOT an abiotic factor?

• Temperature

• Light intensity

• Predation

• pH of soil

How do abiotic factors influence the size of a population?

• They increase competition among species.

• They provide food for the population.

• They have no impact on population size.

• They determine the availability of resources like water and light.

How do abiotic factors like water and light availability affect ecosystems?

• They increase the number of predators in the ecosystem.

• They limit the number of species that can survive.

• They have no effect on the ecosystem.

• They only affect plant species.

What is the main difference between interspecific and intraspecific competition?

• Interspecific competition occurs within the same species, while intraspecific occurs between different species.

• Interspecific competition occurs between different species, while intraspecific occurs within the same species.

• Interspecific competition involves competition for mates, while intraspecific does not.

• Intraspecific competition involves competition for food, while interspecific does not.

Which of the following is a characteristic of predator-prey population graphs?

• Predator and prey populations fluctuate in a cyclical pattern.

• Prey populations remain constant over time.

• Predator populations are always larger than prey populations.

• Predator populations peak before prey populations.

Why do prey populations typically peak at a higher point than predator populations?

• Predators are further along the food chain and require more energy.

• Prey are more efficient at using energy.

• Prey reproduce faster than predators.

• Predators have more food sources than prey.

What happens to predator populations when prey populations decrease?

• Predator populations increase.

• Predator populations decrease.

• Predator populations remain stable.

• Predator populations become extinct.