Principles of Inheritance - Grade 12 Biology

These flashcards cover key vocabulary and concepts related to inheritance, genetics, and associated biological principles as part of Grade 12 Biology curriculum.

Meiosis

A process of cell division that produces haploid gametes (sperm and eggs) from a diploid parent cell, contributing to genetic diversity.

Homozygous

An organism with two identical alleles for a specific trait, either dominant (AA) or recessive (aa).

Heterozygous

An organism with two different alleles for a specific trait (Aa), displaying the dominant trait.

Genotype

The genetic makeup of an organism, represented by the combination of alleles (e.g., AA, Aa, aa).

Phenotype

The observable characteristics or traits of an organism resulting from the genotype.

Punnett Square

A graphical tool used to predict the genotypes and phenotypes of offspring from a genetic cross.

Codominance

A genetic scenario where both alleles in a heterozygote are fully expressed, resulting in offspring with a phenotype that is not a blend (e.g., AB blood type).

Incomplete Dominance

A genetic pattern in which the heterozygous phenotype is an intermediate of the two homozygous phenotypes (e.g., pink flowers from red and white parents).

Central Dogma of Biology

The process where genetic information flows from DNA to RNA to Protein, determining the function of the cell.

Autosomes

Chromosomes that do not determine the sex of an organism; in humans, there are 22 pairs of autosomes.

Sex-linked traits

Traits that are associated with genes located on sex chromosomes, often more commonly expressed in one sex.

Trisomy

A condition in which an individual has an extra chromosome, leading to genetic disorders such as Down syndrome.

Monosomy

A condition in which an individual is missing one chromosome from a pair, often leading to developmental issues.

X-linked inheritance

The inheritance pattern of genes located on the X chromosome, often leading to different expression in males and females.

Pleiotropy

A genetic phenomenon where one gene influences multiple phenotypic traits.

Epistasis

A situation in genetics where one gene masks or modifies the effect of another gene at a different locus.

Additive traits

Traits that are influenced by multiple genes, resulting in a continuous range of phenotypes.

Lethal genes

Alleles that cause the death of the organism when in the homozygous condition.

Ethical issues in genetics

Concerns arising from genetic testing and manipulation, including implications for privacy, consent, and potential discrimination.

Genetic testing

Analyzing DNA to identify genetic disorders that may be passed on to offspring, with implications for medical decisions.

Karyotype

A visual representation of an individual's chromosomes, used to identify chromosomal abnormalities.

Down Syndrome

A genetic disorder caused by trisomy of chromosome 21, characterized by intellectual disability and distinctive facial features.

Turner Syndrome

A condition that occurs when an individual has only one X chromosome, leading to various developmental issues.

Klinefelter Syndrome

A genetic condition in males characterized by an extra X chromosome (XXY), leading to physical and reproductive traits.

Genetic modification

The use of biotechnology to change the genetic makeup of an organism, potentially addressing genetic disorders.