Biodiversity within a community

Question 1

Key terms

Question 2

What is a habitat?

Answer 2

The place where a species lives within an ecosystem.

Question 3

What is a community?

Answer 3

All the populations of the species found in a particular ecosystem at a particular time.

Question 4

What is species diversity?

Answer 4

The number of different species and how many organisms are in each species.

Question 5

What is biodiversity?

Answer 5

The variety of organisms within a certain area.

Question 6

What is variation?

Answer 6

The difference between individuals.

Question 7

What is interspecific variation?

Answer 7

The difference between individuals of different species. This is because organisms have different genes which code for different characteristics and also due to environmental factors.

Question 8

What is intraspecific variation?

Answer 8

The difference between organisms of the same species. This is due to organisms of the same species having the same genes but different alleles of those genes. Also, it is due to environmental factors.

Question 9

What is species richness?

Answer 9

The total number of different species in a community. The higher the species richness the higher the diversity in that community.

Question 10

What is the formula for calculating the index of diversity?

Answer 10

N= The total number of all species in a habitat.
n = The total number of individuals in each species.

Question 11

Why is using the index of diversity to measure species diversity better compared to species richness?

Answer 11

Species richness only takes into account how many species there are but the index of diversity also takes into account the number of individuals in each species. This is a better way to measure diversity because a species with a smaller number of individuals should not be considered as diverse as a species with a higher number of individuals.

Question 12

Why is the index of diversity

Question 13

How does human population growth lead to a decrease in diversity?

Answer 13

1. Deforestation for the development of new homes and the overuse of certain resources leads to some species losing habitats and food. This means that animals of certain species have to move to a different place or they won’t survive. This decreases the species and genetic diversity of that area.
2. Urban sprawl isolates certain species, and that limits breeding in those species, which decreases the genetic diversity.

Question 14

How do certain agricultural practices reduce biodiversity?

Answer 14

1. Removing hedgerows: This decreases the number of species in the area as the habitats that they rely on to love are removed, so they have to move to another area, or they won’t survive.
2. Monoculture decreases biodiversity directly as there will only be one species of plant being grown within a certain area. Those plants will also only support a small number of species.
3. Herbicides decrease biodiversity by killing many species of plants and also taking away food sources from the species that are the weeds the herbicides kill. This means those species die off or move to another area to find another source of food.
4. Pesticides reduce biodiversity by killing many different species.

Question 15

What is conservation?

Answer 15

Meeting the resource needs of the current population but also protecting those resources so that they are available for future generations.

Question 16

What are some conservation methods used to protect biodiversity?

Answer 16

1. Maintaining hedgerows.
2. Using less pesticides and herbicides.
3. Using crop rotation.
4. Protecting certain areas by making deforestation illegal in those areas.