Diversity Classification Variation Flashcards
Gene mutation
Change in the base sequence of chromosomes
Mutagenetic agents
Increase the rate of gene mutation
Factors increasing genetic variation
Independent segregation of homologous chromosomes
Crossover of homologous chromosomes
Random fertilisation of haploid gametes
Genetic diversity
Number of different alleles of a gene in a population
Genetic bottleneck
Event causing a big reduction in a population
Reduces number of different alleles in the gene pool
Reduces genetic diversity
Survivors reproduce and a larger population is created from few individuals
Founder effect
Few organisms from a population start a new colony
Small number of different alleles in the initial gene pool
Higher incidence of genetic disease
Can be a result of migration/ geographical separation
Aseptic techniques
Disinfect surfaces
Contaminated utensils in beaker of disinfectant
Sterile equipment
Discard safely after use
Work near bunsen flame to produce un upwards current of air to remove microbes from the culture
Minimise time spent with lid of agar off
Flame neck of container of broth (of bacteria) to force air out of container
Community
All the populations of different species in a habitat
Biodiversity
Variety of living organisms in an area
Variation
Differences that exist between individuals
Hierarchy
Smaller groups within larger groups
With no overlap between them
Species
Group of similar organisms able to reproduce to give fertile offspring
Species richness
Measure of the number of different species in a community
Index of diversity
Both the species richness and the abundance of each species are taken into account in this measure
Techniques in clarifying evolutionary relationships
Genome sequencing- comparing DNA sequences
Comparing amino acid sequence
Immunological comparisons- similar proteins will also bind the same antibodies
Gene technologies in assessing genetic diversity
Comparing dna base sequences of the same gene to determine number of different alleles of that gene in the population
Comparing mRNA base sequences/ amino acid sequences due to different alleles
Non disjunction
Failure of separation of homologous chromosomes in meiosis 1
Phylogenetic classification
Arranges species into groups based on their based on their evolutionary origins and relationships
Smaller groups placed within larger groups
No overlap
Hierarchy
Agricultural practices that reduce biodiversity
Woodland clearance- reduces number of trees and number of different species, destroys habitats, causes migration
Hedgerow removal
Pesticides- also affects predators of the insects it kills
Herbicides- reduced diversity and affects organisms feeding on the weeds
Monoculture- reduces biodiversity and supports fewer organisms
How can genetic diversity within or between species be determined
Comparing frequency of measurable or observable characteristics
Comparing base sequence of DNA/mRNA/amino acid sequences
Quantitative investigations of variation involve
Collecting data from random samples
Calculating mean and the SD of that mean
Interpretation
Describe how organisms are grouped in a phylogenetic classification system
Hierarchy with no overlaps/ smaller group within laser groups
Grouped according to the evolutionary origins/ relationships/ history
