4.6 Biodiversity within a community 4.7 Investigating diversity Flashcards
What is biodiversity?
The variety of living organisms. It can be measured in terms of species diversity, ecosystem diversity and genetic diversity.
Define community
All the different species that live in one area and interact with each other
What impact does farming have on species diversity?
Decreases species richness
1. farmland is typically used for only 1 species
2. use of pesticides/ herbicides
What impact does farming have on genetic diversity?
decreases
1. farmers select for certain characteristics, which reduces number of different alleles in the population
How can biodiversity be increased in areas of agriculture?
- Use hedgerows instead of fences.
- Grow different crops in the same area, or rotate crops around after a season.
- Limit use of pesticides and herbicides.
Name four ways we can compare genetic diversity between organisms.
- Frequency of observable characteristics.
- Base sequence of DNA.
- Base sequence of mRNA.
- Amino acid sequence
Define gene technology
sampling DNA or mRNA in order to read and compare the base sequence of organism.
Why do scientists prefer to use gene technology instead of observation?
Simply inferring DNA differences by observing an organism’s characteristics is not reliable; the characteristics could be coded for by more than one gene, or could be influenced by the environment.
What is meant by interspecific and intraspecific variation?
Interspecific = differences between individuals of different species.
Intraspecific = differences between individuals of the same species
Define sampling
Selecting a group of individuals to measure that will represent the whole target population
How can a random sample be achieved?
Create a grid for your sample area, and then randomly generate coordinates where a quadrant or transect can be placed. Repeat until required sample size is reached.
