Biology 1030: Human Anatomy and Physiology 1 - Genetics

Vocabulary flashcards generated from Biology 1030 Human Anatomy and Physiology 1 lecture notes on Genetics, covering DNA, genes, protein synthesis, mutations, inheritance patterns, and chromosomal disorders.

Genes

Sequences of nucleotides in DNA that contain blueprints for proteins.

mRNA (Messenger RNA)

A copy of a gene produced using the DNA blueprint, which goes out to the cytoplasm.

Ribosome

A cellular structure that uses information in mRNA and available amino acids to make a protein.

Transcription

The production of messenger RNA (mRNA) using a DNA template, occurring in the nucleus for one gene at a time.

RNA Polymerase

An enzyme that builds an mRNA polymer, using DNA as a template and available RNA nucleotides.

Translation

The process where ribosomes 'read' mRNA instructions in the cytoplasm to make a specific protein, converting nucleic acid language to protein language.

Genetic Code

The dictionary between nucleic acid language and protein language.

Triplet Codon

A nucleic acid 'word' of three RNA nucleotides that encodes for one amino acid.

Redundant Code

The characteristic of the genetic code where 64 possible combinations of three nucleic acids code for only 20 amino acids, allowing some mutations to be 'silent'.

Silent Mutation

A mutation that changes the DNA and mRNA sequence, but due to the redundancy of the genetic code, does not change the resulting amino acid (and thus, the protein).

Start Codon

A special codon that signals the beginning of protein synthesis.

Stop Codons

Special codons that signal the end of protein synthesis.

Protein Modification

Alterations to proteins whose location and process depend on the type of protein, occurring in the cytoplasm or Golgi apparatus.

Genotype

The specific alleles (versions of genes) present in an individual.

Phenotype

The observable traits produced by the alleles in an individual.

Allele

An alternate version of a gene that determines a variation of a trait, arising through past germline mutations.

Mutations

The source of new alleles.

Germ-line Mutation

A mutation occurring in sperm or egg cells that can be passed down through generations.

Somatic Mutation

A mutation occurring in body cells that is not passed down to offspring.

Missense Mutation

A mutation that changes the amino acid sequence in a protein, often caused by mistakes during DNA replication or exposure to mutagens.

Nonsense Mutation

A mutation that introduces an early STOP codon into the mRNA sequence, resulting in a protein that is severely shorter or non-functional.

Homozygous

A condition where the two alleles for a gene in an individual are the same.

Heterozygous

A condition where an individual has two different alleles for a gene.

Multiple Alleles

An inheritance pattern where more than two alternative alleles exist for a given gene (e.g., ABO blood type).

Complete Dominance

An inheritance pattern where the dominant allele determines the trait if present, and the recessive allele determines the trait only if the dominant isn't also present.

Codominance

An inheritance pattern where both alleles that a person has show their distinct effects in the phenotype (e.g., AB blood type).

Incomplete Dominance

An inheritance pattern where heterozygous organisms show a phenotype intermediate (blended) between the two alleles.

Sickle Cell Anemia

A disease resulting from a homozygous recessive genotype (HbS HbS), characterized by reduced blood flow and pain due to a mutation in the hemoglobin gene.

Sickle Cell Trait

A characteristic exhibited by heterozygous individuals (HbA HbS) who do not have sickle cell anemia but may show some symptoms in low oxygen conditions, and it appears to provide protection against malaria.

Polygenic Inheritance

A trait inheritance pattern where some traits depend upon the simultaneous inheritance and expression of more than one gene.

Karyotype

An imaging technique used to visualize the complete set of chromosomes, numbered by homologous pairs and showing specific staining patterns.

Meiosis

The process of cell division occurring only in germline cells that results in four haploid gametes (egg and sperm), each genetically different and with only one set of chromosomes.

Gametes

Reproductive cells (egg and sperm) produced through meiosis.

Homologous Chromosomes

Pairs of chromosomes that are similar in size and genetic content, which pair up during meiosis.

Crossing Over

The exchange of genetic material between homologous chromosomes during meiosis, further randomizing the set of alleles passed down.

Punnett Square

A diagrammatic tool used to calculate and predict inheritance patterns.

Nondisjunction

An alteration in chromosome numbers during meiosis, which can lead to the addition or loss of chromosomes in gametes.

Down Syndrome (Trisomy 21)

A genetic condition caused by having three copies of chromosome 21 (47 chromosomes), with increasing risk in older mothers.

Klinefelter Syndrome

A genetic condition in males with an XXY genotype (49 chromosomes).

Turner Syndrome

A genetic condition in females with an XO genotype (less than 46 chromosomes).

Sex-linked Genes

Genes located on the sex chromosomes (X and Y), with traits determined by differences between these chromosomes.

X Chromosome

A sex chromosome that is larger than the Y chromosome, containing hundreds of genes; females have two X chromosomes.

Autosomes

The first 22 pairs of chromosomes in a human karyotype, not including the sex chromosomes.

Sex Chromosomes

The last pair of chromosomes (X and Y) in a human karyotype, determining an individual's biological sex.