Inheritance, Variation and Evolution

A version of a gene

Small molecules from which proteins are assembled

Primitive bacteria existing in extreme environments

A form of reproduction involving a single parent.

Creates gentically identical offspring

The univeral system of naming organisms using genus and species

The scientist who developed the theory of evolution by natural selection

A long, coiled molecule of DNA that carries genetic information in the form of genes

The organisation of organisms into groups based on their characteristics and structure

 A cellular membrane disorder resulting from the presence of a recessive allele

 A double-stranded polymer wound to form a double helix.

Carries the genetic code. 

 Describes an allele that is always expressed.

Represented by a capital letter. 

 A procedure used to determine the presence of faulty genes in an embryo produced by IVF.

A few embryonic cells are removed and screened for defective alleles.

The gradual change in the inherited traits within a population over time.

Occurs due to natural selection. 

A diagram which illustrates the evolutionary relationships between organisms

The death of all members of a species. 

 A chart used to show the inheritance of a condition in a family. 

The fusion of the nucleus of male and female gametes. 

 Restores the full chromosome number.

The remains of dead organisms found in rocks which are millions of years old. 

 Sex cells (sperm and egg cells) with half the usual number of chromosomes. 

A section of DNA that codes for a specific sequence of amino acids which undergo polymerisation to form a protein. 

 The modification of the genome of an organism by the insertion of a desired gene from another organism, enabling the formation of organisms with benefical characteristcs 

The complete genetic material of an organism. 

An organism’s genetic composition.

Describes all alleles. 

Crops that have had their genomes modified by the insertion of a desired gene from another organism

When someone has two different alleles of a gene e.g. Ff. 

When someone has two identical alleles of a gene e.g. ff.

The formation of offspring from the breeding of closely related individuals. 

The classification of organisms into kingdom, phylum, class, order, family, genus and species, as developed by Carl Linnaeus. 

A form of cell division that produces gametes, non-identical cells with half the usual number of chromosomes. 

 A form of cell division that produces two genetically identical daughter cells (with a full set of chromosomes) from one parent cell. 

A type of bacteria that is resistant to the antibiotic, methicillin. 

 A random change in DNA which may result in genetic variants. 

The process by which the frequency of advantageous traits passed on in genes gradually increases in a population over time. 

An organism’s observable characteristics. Due to interactions of the genotype and the environment. 

 A condition where an individual is born with extra fingers or toes due to the presence of a dominant allele. 

 A grid used to predict the potential outcomes of a genetic cross. 

Describes an allele that is only expressed in the absence of a dominant allele. 

Represented by a small allele

 Sub-cellular structures where protein synthesis takes place. 

 The process by which humans artificially select organisms with desirable characteristics and breed them to produce offspring with desirable phenotypes. 

A pair of chromosomes responsible for the determination of gender.

XY in males. ** in females. 

 A form of reproduction involving the fusion of male and female gametes.

Creates genetic variation. 

A group of similar organisms that are able to breed with one another to produce fertile offspring. 

A method of classification in which organisms are categorised into three groups; Archaea, Bacteria and Eukaryota.

Developed by Carl Woese. 

The differences between individuals due to genes, the environment or a combination of both.

A carrier used to transfer a gene from one organism to another