Great Big Honors Biology Exam Review

Flashcards for Genetics, Heredity, and Evolution

DNA

Deoxyribonucleic acid, a molecule that carries genetic instructions.

RNA

Ribonucleic acid, a molecule that plays a role in protein synthesis.

Central Dogma of Genetics

The process by which DNA is transcribed into RNA, which is then translated into protein.

Transcription

The process of creating RNA from a DNA template.

Translation

The process of creating a polypeptide chain from an mRNA template.

Eukaryotes

Organisms whose cells have a nucleus enclosed within a nuclear envelope.

mRNA

Messenger RNA; carries the genetic code from DNA to ribosomes.

Polypeptide

A chain of amino acids linked together by peptide bonds.

Mutation

A change in the DNA sequence.

Meiosis

A type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell.

Cell Cycle

The series of events that take place in a cell leading to its division and duplication.

Complete Dominance

A form of dominance in heterozygous condition wherein the allele that is regarded as dominant completely masks the effect of the recessive allele.

Punnett Square

A diagram used to predict the genotypes and phenotypes of offspring.

Recessive Genotype

A genotype where the effects of the allele are masked in the presence of a dominant allele.

Phenotype

The observable characteristics or traits of an organism.

Karyotype

The number and appearance of chromosomes in the nucleus of a eukaryotic cell.

Genetic Abnormalities

Variations in genes that are associated with disease of disorder.

Natural Selection

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

Evolution

Change in the heritable characteristics of biological populations over successive generations.

Cladogram

A diagram used to show the evolutionary relationships among a group of organisms.

Codon Chart

A table that provides the link between mRNA codons and the amino acids they encode.

TAC

A DNA sequence that codes for the start codon.

AUG

A codon that codes for methionine and also serves as a start codon.

UGA

A stop codon that signals the end of translation.

Heredity

The passing on of traits from parents to their offspring.

Allele

One of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome.

Dominant Trait

A trait that appears in the offspring if one of the parents contributes the dominant allele.

Chromosome

A thread-like structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

Gene

A unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

Genotype

The genetic constitution of an individual organism.

Heterozygous

Having two different alleles of a particular gene or genes.

Homozygous

Having two identical alleles of a particular gene or genes.

Recessive Trait

A genetic trait that is masked by a dominant trait.

Ribosome

A structure upon which proteins are assembled.

Trait

A distinguishing quality or characteristic, typically one belonging to a person.

Evolutionary Standpoint

A perspective that considers the history and ongoing process of biological evolution.

DNA Replication

The biological process of producing two identical replicas of DNA from one original DNA molecule.

RNA Polymerase

An enzyme that is responsible for copying a DNA sequence into an RNA sequence, during the process of transcription.

tRNA

An adaptor molecule composed of RNA, typically 76 to 90 nucleotides in length, that serves as the physical link between the mRNA and the amino acid sequence of proteins.

Codon

A sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule.

Anticodon

A sequence of three nucleotides forming a unit of genetic code in a transfer RNA molecule, corresponding to a complementary codon in messenger RNA.

Amino Acid

Organic compounds that combine to form proteins.

Peptide Bond

A chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water.

Gene Expression

The process by which information from a gene is used in the synthesis of a functional gene product.

Genetic Code

The set of rules used by living cells to translate information encoded within genetic material into proteins.

Genetic Variation

The difference in DNA among individuals or the differences between populations.

Adaptation

The process by which an animal or plant becomes fitted to its environment; it is the result of natural selection acting upon heritable variation.

Fitness

The ability of an organism to survive and reproduce in its environment.

Evolutionary Tree

A branching diagram or 'tree' showing the evolutionary relationships among various biological species or other entities.

Taxonomy

The branch of science concerned with classification, especially of organisms; systematics.