Biodiversity, Species and Taxonomy Flashcards
What is meant by biodiversity? (1)
number of individuals of each species within the community
What is meant by species richness? (1)
number of different species in a community
What is meant by a community? (1)
ALL individuals of ALL species living together in the same area at the same time
What is a species? (2)
- Group of similar organisms
- Reproduce to produce fertile offspring
Explain what is meant by a hierarchy? (2)
- Groups within groups
- No overlap between groups
Explain what is meant by a phylogenetic group (1)
grouped according to evolutionary links
Explain what is meant by genetic diversity (1)
difference in DNA base sequence
Explain what is meant by a niche (2)
- An organisms role in the community / ecosystem
- How organisms interact with other species and responds to the environment
How to calculate diversity index?
( N (n - 1) ) / sum of n (n-1)
N = total number of organisms of ALL species
n = total number of organisms of EACH species
What information is required to calculate an index of diversity for a particular community? (2)
- Number of species
- Number of individuals of each species
List the order of the hierarchy. Start with the largest group.
- Domain
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
Give two ways doctors could use base sequences to compare different types of HPV (3)
- Compare DNA base sequence
- Compare mRNA base sequence
- Look for mutations
State three comparisons of genetic diversity that the scientist could have used to generate a classification (3)
- DNA base sequence
- mRNA base sequence
- Amino acid sequence
The number of species present is one way to measure biodiversity. Explain why an index of diversity may be a more useful measure of biodiversity. (2)
- Measures number of individuals in a species
- Some species may be present in low/high numbers
In classification, comparing the base sequence of a gene provides more information than comparing the amino acid sequence for which the gene codes. Explain why. (3)
- More bases than amino acids / longer base sequence than amino acid sequence
- Introns/non-coding DNA;
- Same amino acid may be coded for / DNA code is degenerate
Scientists’ analysis of blood proteins has indicated a lack of genetic diversity in populations of some organisms. Describe the processes that lead to a reduction in the genetic diversity of populations of organisms. (6)
- Reduced variety/number of different alleles / reduced gene pool
- Founder effect
- A few individuals from a population become isolated/form colonies
- Genetic bottlenecks
- (Significant) fall in size of population
- Selective breeding / artificial selection
- Using organisms with particular alleles / phenotypes / characteristics
Scientists can use protein structure to investigate the evolutionary relationships between different species. Explain why. (3)
- Amino acid sequences / primary structure
- Closer the amino acid sequence the closer the relationship
- Protein structure related to (DNA) base sequence
A forest was cleared to make more land available for agriculture. After the forest was cleared the species diversity of insects in the area decreased. Explain why. (4)
- Decrease in variety of plants / fewer plant species
- Fewer habitats and niches
- Decrease in variety of food / fewer food sources
- Clearing forest resulted in killing insects due to machinery or pesticides
What is meant by a genetic bottleneck? (2)
- Sudden decrease in population / many killed by an event eg earthquake
- Reduced genetic variation / reduction in (variety of) alleles
Suggest one ethical argument for maintaining biodiversity. (1)
Prevent extinction
Prevent reduction in populations
Prevent loss of habitats
Suggest three economical arguments for maintaining biodiversity. (3)
- Medical uses
- Commercial products
- Tourism
- Agriculture
- Saving local forest communities
Farmers clear tropical forest and grow crops instead. Explain how this causes the diversity of insects in the area to decrease. (4)
- Fewer plant species
- Fewer food sources
- Fewer habitats and niches
- Fewer (species of) herbivore so few (species of) carnivores
- Clearing forest resulted in killing insects due to machinery or pesticides
Describe how courtship behaviour increases the probability of successful mating. (5)
- Attracts same species
- Attracts mate/opposite sex
- Allows sexual maturity/ fertility / synchronises mating
- Stimulates release of gametes
- Form pair bond