Biodiversity (4.1-4.6) Flashcards
Adaptation
The changes organisms undergo to become more suited to their environment
Anatomical adaptations
Changes to the physical features of an organism
Behavioural adaptations
The ways in which an organism acts differently to cope with factors in its environment
Biodiversity
A measure of the variety of life in an area
Classification
A means of organising the variety of life based on the relationship between organisms using differences and similarities in phenotypes and genotypes
Endemism
A species which only exists in a certain area
Evolution
The changes in a populations characteristics over time
Hardy-Weinberg principle
A principle which states that the frequency of alleles in a. population will not change ever time unless evolutionary factors are present
Hardy Weinburg formula
p2 + 2pq + q2 = 1
p2 = frequency of homozygous dominant 2pq = Frequency of heterozygous q2 = Frequency of homozygous recessive
Heterozygosity index (H)
A measure of the proportion of a population which is heterozygotic which can be calculated using:
Number of heterozygotes H = ----------------------------------------------------------
Number of individuals in the population
Index of diversity (D)
A measure of the diversity of a population which takes into account the number and abundance of a species and can be used to compare different habitats using the equation:
N(N-1) D = ----------------
En(n-1)
N = Total number of organisms n = Total number of organisms of the species of interest
Natural selection
Where better adapted organisms are able to survive and reproduce which causes the population to become better adapted over time
Physiological adaptations
The internal body changes that an organism undergoes to cope with factors in its environment
Reproductive isolation
The inability of some organisms of a species to breed with other members of the same species due to barrier
Species
Organisms that can breed together to produce fertile offspring
