4 Genetic Information & variation- Biodiversity within a community

Question 1

What is biodiversity?

Answer 1

-The complexity of a biological community
-Can relate to a range of habitats, from a small local habitat to the Earth
-Can be measured using species richness
-Varies between different habitats

Question 2

What is species richness?

Answer 2

A measure of the number of different species in a community, can be found by counting the different species in a habitat

Question 3

What does index of diversity describe?

Answer 3

Describes the relationship between the number of species (species richness) in a community and the number of individuals (species abundance) in each species

Question 4

How is the index of diversity (d) calculated?

Answer 4

d = N (N-1)/ N= total number of organisms of all species present
Σ n(n-1) n= total number of organisms of one given species present

Question 5

What is the benefit of using the index of diversity over species richness?

Answer 5

Takes into account the population sizes of different species in one community

Question 6

What are the ways in which agriculture can reduce biodiversity?

Answer 6

Monoculture, herbicides, pesticides and deforestation

Question 7

What is monoculture and how does it reduce biodiversity?

Answer 7

• A single crop species covering many fields when crops are grown on a large scale
• Directly decreases biodiversity, as fewer species can survive in monoculture environments

Question 8

What are herbicides and how do they reduce biodiversity?

Answer 8

-Are sprayed onto crops to prevent growth of unwanted plants & weeds
-Reduce biodiversity as they directly remove plants and species that feed on the unwanted plants cannot survive

Question 9

What are pesticides and how do they reduce biodiversity?

Answer 9

-Are sprayed onto crops to prevent pests (e.g. slugs) from feeding on crops
-Reduces biodiversity as they directly remove pests and species that feed on the pests cannot survive

Question 10

What is deforestation and how does it reduce biodiversity?

Answer 10

-Large regions of forests are cleared to make space for crop/ livestock farms
-Reduces biodiversity as it directly removes species (e.g. trees) and removes habitats, causing species to die

Question 11

What are some conservation schemes to avoid agricultural impacts?

Answer 11

-Protecting endangered species to avoid extinction
-Protecting areas with high biodiversity, so they can’t be made into farmland
-Farmers encouraged to balance agriculture with conserving biodiversity

Question 12

Why is conservation vs. farming an issue?

Answer 12

Agriculture can have many negative impacts but it is necessary to support the growing human population. The balance between conserving species and farming can be a conflicting issue