Definitions Flashcards
Biological Evolution
Is a special type of evolution that refers to changes that living things have undergone over long periods of time
Hypothesis
A statement that can be tested and explains an observation. Informed assumption and provides a solution based an evidence and observation.
A theory
Is a final conclusion reached after testing many hypothesis and which contains evidence. Well substantiated explanation which is developed and changed as new evidence is discovered.
Biological Species
A group of organisms with similar characteristics that interbreed with one another to produce fertile offspring
Population
A group of individuals of the same species occupying a particular habitat.
Lamarcks theory of inheritance a of acquired characteristic
Modification acquired by an organism during its lifetimes would be passed onto its offspring
Speciation
is the evolution of a new species and increased biodiversity.
Extinction
The process by which all individuals die off and not even a single one of the entire of species exists .
Mechanism for reproductive Isolution
1- Breeding @ different times of the year
2- Species specific courtship behaviours
3- Adaptations to different pollination
4- Prevention of fertilisation
5- Infertile Offspring
Out of Africa Hypothesis
All modern humans originated in southern africa
They then migrated to other parts of the world
Mendles law of segregation
Each trait is controlled by 2 alleles found in homologous chromosomes
2) gametes form (meiosis) two alleles separate
3) gamete only has 1 allele
Law of dominance
Alleles of genes exist either dominant or recessive
2) if pair of alleles heterozygous genotype then phenotype will show only dominant trait
Law independent assortment (di-hybrid cross)
Due to random arrangement of chromosomes at the equator (meiosis)
Any 2 alleles of one characteristic can sort with any other allele of another characteristics. Alleles of different genes move independently of each other into gametes
