Biology: Heredity and Genetics

Heredity

Definition

• Heredity refers to the passing of traits or characteristics from parents to offspring through the transmission of genetic information.

Key Concepts

• Genes: units of heredity that carry information from one generation to the next
• Genotype: the complete set of genes an individual possesses
• Phenotype: the physical and behavioral characteristics of an individual that result from the interaction of their genotype and the environment
• Inheritance patterns: the way genes are passed down from parents to offspring, including dominant and recessive traits

Evolution

Definition

• Evolution is the change in the inherited characteristics of a population of organisms over time.

Mechanisms of Evolution

• Mutation: a change in the DNA sequence of an individual, resulting in a new allele
• Genetic drift: the random change in the frequency of an allele in a population over time
• Gene flow: the movement of genes from one population to another, resulting in increased genetic variation
• Natural selection: the process by which individuals with favorable traits are more likely to survive and reproduce, passing those traits on to their offspring

Types of Evolution

• Microevolution: the change in the frequency of alleles within a population over a relatively short period of time
• Macroevolution: the change in the characteristics of a species or group of species over a longer period of time, resulting in the formation of new species

Evidence for Evolution

• Fossil record: the pattern of fossil formation and discovery, showing gradual changes in species over time
• Comparative anatomy: the study of the similarities and differences in the structure of body parts among different species
• Molecular biology: the study of DNA and protein sequences, showing similarities and differences among different species

Heredity

• Heredity is the passing of traits or characteristics from parents to offspring through the transmission of genetic information.
• Genes carry information from one generation to the next and are the units of heredity.
• Genotype refers to the complete set of genes an individual possesses.
• Phenotype is the physical and behavioral characteristics of an individual that result from the interaction of their genotype and the environment.
• Inheritance patterns include dominant and recessive traits, which determine how genes are passed down from parents to offspring.

Evolution

• Evolution is the change in the inherited characteristics of a population of organisms over time.
• Mutation is a change in the DNA sequence of an individual, resulting in a new allele.
• Genetic drift is the random change in the frequency of an allele in a population over time.
• Gene flow is the movement of genes from one population to another, resulting in increased genetic variation.
• Natural selection is the process by which individuals with favorable traits are more likely to survive and reproduce, passing those traits on to their offspring.

Types of Evolution

• Microevolution is the change in the frequency of alleles within a population over a relatively short period of time.
• Macroevolution is the change in the characteristics of a species or group of species over a longer period of time, resulting in the formation of new species.

Evidence for Evolution

• Fossil record shows gradual changes in species over time, with fossil formation and discovery following a pattern.
• Comparative anatomy studies the similarities and differences in the structure of body parts among different species.
• Molecular biology studies DNA and protein sequences, showing similarities and differences among different species.

Learn about the fundamentals of heredity, including genes, genotype, phenotype, and the transmission of traits from parents to offspring.