Biology Exam Revision PPT

Genetic Mutation

A permanent change in the DNA sequence that can occur in one or more genes.

Mutagens

Factors that can increase the chance of mutations occurring, including radiation, chemicals, and UV light.

Genetic Mutation

A permanent change in the DNA sequence that can occur in one or more genes.

Mutagens

Factors that can increase the chance of mutations occurring, including radiation, chemicals, and UV light.

Negative Mutations

Harmful mutations that can result from radiation, chemicals, or UV exposure, potentially leading to conditions like cancer.

Natural Selection

The process by which individuals that are best suited to their environment survive and pass on their genes.

Speciation

The process by which one species splits into two or more new species, involving variation, isolation, and selection.

Allele Frequency

How common an allele is in a particular population, affected by environmental conditions.

Divergent Evolution

When a single species evolves into two or more different species, retaining some common characteristics.

Convergent Evolution

When two or more different species develop similar structures to perform similar tasks due to similar selection pressures.

Variation

The occurrence of different traits within a population due to genetic mutations, contributing to the diversity of species.

Fossil Record

The remains or traces of organisms from a past geological age, helping to understand extinct species and fill in evolutionary gaps.

Embryology

The study of how an embryo develops, showing similarities that suggest a common ancestor among different vertebrates.

Comparative Anatomy

The study of similarities and differences in the anatomy of different organisms, providing evidence for evolution.

Homologous Structures

Similar structures in different organisms that indicate a common ancestor.

Vestigial Structures

Functionless structures in organisms that provide evidence of evolution, indicating traits that were once useful.

DNA and Protein Similarities

Similarities in DNA and protein structures that indicate how closely related species are, affected by mutations over time.