studyden bio220 notes

Genome

The total set of DNA in an organism, including genes and non-coding sequences.

Endosymbiotic event

A process in which one organism lives inside another, leading to a symbiotic relationship, as in the origin of mitochondria and chloroplasts.

Heterogametic sex

The sex that produces different types of gametes (e.g., males produce X and Y gametes), as seen in humans.

Uniparental inheritance

Genetic transmission from one parent, as observed with mitochondria and Y chromosomes.

Biparental inheritance

Genetic transmission from both parents, as in the case of autosomes and X chromosomes.

Mitochondrial DNA

DNA found in mitochondria, inherited maternally; used to trace maternal lineages.

Autosomes

Chromosomes that are not sex chromosomes; inherited equally from both parents.

Inbreeding depression

Reduced biological fitness in a population due to inbreeding, which can lead to higher frequencies of deleterious recessive traits.

Paternity analysis

A genetic analysis to determine the biological father of an offspring.

Polymorphism

The occurrence of two or more distinct forms (alleles) at a locus in the genome within a population.

Assortative mating

Mating preference for partners with similar phenotypes or genotypes.

Convergent evolution

Independent evolution of similar traits in different species due to similar environmental pressures.

Gene flow

Transfer of genetic material between populations, which can counteract the effects of inbreeding and promote genetic diversity.

Phenotype

An individual's observable traits or characteristics, influenced by both genotype and environmental factors.

Cultural evolution

Changes in human culture and behavior that influence genetic selection pressures, such as dietary practices.

Genetic drift

Random fluctuations in allele frequencies within a population due to chance events, particularly in small populations.

Selection pressures

Environmental factors that influence the survival and reproduction of organisms, altering allele frequencies in a population.

Heterozygosity

The presence of different alleles at a gene locus in an individual, often associated with higher fitness in populations.

Fitness

The ability of an organism to survive and reproduce, contributing to the gene pool of the next generation.

Artificial selection

Human-directed breeding processes to enhance desired traits in plants and animals.

Ecosystem stability

The ability of an ecosystem to maintain its structure and function over time despite external stress or changes.

Conservation genetics

The study of genetic variation within and between populations for the purpose of conserving and managing biodiversity.

Mating system

The way in which a species forms pairs for reproductive purposes, which can influence genetic diversity.

Ecological niche

The role or function of an organism or species within an ecosystem, including its habitat, resource use, and interactions with other species.

Demographic transition model

A model that describes population change over time through various stages of development characterized by changes in birth and death rates.

What is a haploid number?

The number of chromosomes in a germ cell, half the diploid number, found in sperm and eggs.

What is the role of ribosomes in a cell?

Ribosomes are the cellular structures where protein synthesis occurs.

What is natural selection?

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

What are mutations?

Changes in the DNA sequence that can lead to variations in traits and may affect an organism's fitness.

What is a phenotype?

The observable physical or biochemical characteristics of an organism, influenced by genotype and environment.

What is an allele?

A variant form of a gene that can produce different traits in an organism.

What is genetic recombination?

The process during meiosis where genetic material is shuffled and genes are rearranged, leading to increased genetic diversity.

What is speciation?

The process by which new species arise, often due to genetic divergence.

What is the function of chloroplasts?

Chloroplasts are organelles in plant cells responsible for photosynthesis, converting light energy into chemical energy.

What is the significance of the Hardy-Weinberg principle?

It describes the genetic variation in a population under certain ideal conditions and is used to predict allele frequencies.

Gene expression

The process by which information from a gene is used to synthesize a functional gene product, usually a protein.

Transcription

The first step of gene expression, where a segment of DNA is copied into RNA.

Translation

The process in which ribosomes synthesize proteins using mRNA as a template.

Chromatin

Complex of DNA and proteins that forms chromosomes within the nucleus of eukaryotic cells.

Operon

A group of genes regulated together, typically found in prokaryotic organisms.

Epigenetics

Study of changes in gene expression without alteration of the DNA sequence, often influenced by environmental factors.

Ribosomal RNA (rRNA)

A type of RNA that, together with proteins, makes up the ribosomes.

mRNA splicing

The process of modifying pre-mRNA by removing introns and joining exons to produce mature mRNA.

Signal transduction

The process by which cells respond to external signals through a series of molecular events.

Homeotic genes

Genes that control the body plan of an embryo along the head-tail axis, determining the identity of body segments.