BIO BENCHMARK 2

Meiosis

A type of cell division that produces gametes (sperm and egg) with half the number of chromosomes.

Law of Dominance

A dominant allele masks a recessive allele.

Law of Independent Assortment

Genes for different traits assort independently during gamete formation.

Law of Segregation

Each parent passes one allele to offspring.

Genetic Variation

New combinations from meiosis, viable errors during replication, and mutations caused by environmental factors.

Mutations

caused by environmental factors (radiation, chemicals, etc.)

Nondisjunction

Failure of chromosomes to separate properly during meiosis, leading to disorders like Down syndrome.

Punnett Squares

Tools used to predict possible genetic outcomes.

Genotypic Ratio

The probability of inheriting specific genetic traits.

Phenotypic Ratio

The probability of expressing specific traits in the phenotype.

Gene Flow

Movement of alleles between populations, such as migration.

Genetic Drift

Random changes in allele frequencies in a population, including Founder Effect and Bottleneck Effect.

Founder Effect

A small group starts a new population.

Bottleneck Effect

Population size drastically decreases, reducing genetic diversity.

Homologous Structures

Structures that have the same origin but different functions, indicating common ancestry.

Analogous Structures

Structures that serve the same function but do not share a common ancestry.

Vestigial Structures

Body parts that have lost their original function through evolution.

Natural Selection

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

Adaptation

Traits that enhance the survival and reproduction of organisms within a population.

DNA Structure

A double helix made of nucleotides (adenine, thymine, cytosine, guanine).

Transcription & Translation

The processes by which DNA is converted to mRNA and then translated into protein.

Mitosis

A type of cell division for growth, repair, and asexual reproduction resulting in two identical diploid daughter cells.

Macromolecules

Large molecules necessary for life, including carbohydrates, proteins, lipids, and nucleic acids.

Environmental Changes & Evolution

1. Increase numbers in some species.

2. Cause the emergence of new species.

3. Lead to extinction of others.