Grade 12 Life Sciences Study Guide

A series of vocabulary flashcards based on key concepts from the Grade 12 Life Sciences lecture notes.

DNA Replication

The process of making identical copies of DNA, essential for cell division.

Transcription

The process by which DNA is copied into mRNA.

Translation

The process of synthesizing proteins from mRNA instructions.

Meiosis

A type of cell division that reduces the chromosome number by half, resulting in four haploid cells.

Fertilisation

The fusion of sperm and ova to form a zygote.

Homeostasis

The maintenance of a stable internal environment within an organism.

Gene Mutation

A change in the nucleotide sequence that can alter the structure and function of a gene.

Chromosomal Mutation

Changes to the structure or number of chromosomes, which can result in genetic disorders.

Phenotype

The observable characteristics of an organism as a result of genotype and environment.

Genotype

The genetic makeup of an organism.

Sex-Linked Disorder

A genetic disorder associated with a gene that is located on one of the sex chromosomes.

Pedigree Chart

A diagram that shows the occurrence of a genetic trait across generations.

Autosomal Recessive Disorder

A disorder that requires both alleles to be recessive for the disorder to be expressed.

Complete Dominance

A genetic situation in which one allele completely masks the effect of another allele.

Co-Dominance

A situation in which both alleles in a heterozygote are fully expressed, resulting in a phenotype that is neither dominant nor recessive.

Incomplete Dominance

A genetic situation in which one allele is not completely dominant over the other, resulting in a blended phenotype.

Dihybrid Cross

A genetic cross that examines the inheritance of two different traits.

Natural Selection

The process whereby organisms better adapted to their environment tend to survive and produce more offspring.

Evolution

The change in the heritable characteristics of biological populations over successive generations.

Monohybrid Cross

A genetic cross examining the inheritance of a single trait.

Genetic Engineering

The direct manipulation of an organism's genes using biotechnology.

Hormones

Chemical substances produced in the body that regulate the activity of cells or organs.