Heredity Vocab

The working heredity vocab from the 2020 heredity team.

Allele

alternate forms of a gene. Usually there are two alleles for every gene, sometimes there are more than two alleles present in population – termed multiple alleles

Gene

a unit of inheritance that usually is directly responsible for one trait or character. Each individual has two genes for each trait, one comes from dad and the other from mom.

Homozygous

when the two alleles are the same. A genotype carrying two dominant or two recessive alleles. One allele is inherited from the father, and the other, from the mother

Heterozygous

when the two alleles are different. A genotype carrying one dominant and one recessive allele.

Dominant

a trait (allele) that is expressed regardless of the second allele

Recessive

a trait that is only expressed when the second allele is the same (e.g. short plants are homozygous for the recessive allele)

Phenotype

the physical expression of the genes for the trait by an individual.

Genotype

the gene makeup of an organism. Phenotype is the trait of an individual expresses while genotype is the two genes that cause that trait. It is the genetic code one inherits for a trait.

Gamete

a mature haploid male or female germ cell which is able to unite with another of the opposite sex to form a zygote.

Operon

a unit made up of linked genes which is thought to regulate other genes responsible for protein synthesis

Sigma Factor

A protein needed for initiation of transcription in bacteria. It is a bacterial transcription initiation factor that enables specific binding of RNA polymerase to gene promoters

Eukaryotic Cells

Cells with a membrane and organelles

Exons

a segment of a DNA or RNA molecule containing information coding for a protein or peptide sequence

Enzymes

Carry out almost all of the chemical reactions that take place in cells. They also assist with the formation of new molecules by reading the genetic information stored in DNA

Mitosis

Cell division in which the nucleus divides into nuclei containing the same number of chromosomes

Meiosis

Cell division that produces reproductive cells in sexually reproducing organisms

Incomplete Dominance

One allele is not completely dominant over the other

Co

dominance

Hybrid

Blending of two traits

Sex

linked Traits

Pedigree

Genetic representation of a family tree that shows the inheritance of a trait or disease through several generations

Polygene

a gene whose individual effect on a phenotype is too small to be observed, but which can act together with others to produce an observable variation.

Multiple Alleles

three or more alleles for a gene. E.g. blood type or skin color

Protein

Large complex molecule necessary for building structural components in the body

Transcription

Process by which mRNA is decoded and a protein is produced

Translation

Process by which mRNA is decoded and a protein is produced

Cytokinesis

the division of the cytoplasm to make 2 new cells

Haploid

Have just one chromosome from each homologous pair

Diploid

a cell or nucleus containing 2 complete sets of chromosomes

Down Syndrome

also called trisomy 21, a disorder that causes developmental and intellectual delays. It is caused by an extra chromosome in pair 21.

Patau Syndrome

also called trisomy 13, symptoms may include an abnormally small head, birth defect with intestinal organs outside of the body, failure to thrive, or low birth weight. Also common are cleft lip and cleft palate, episodes of no breathing, flaccid muscles, having extra fingers or toes, heart murmur, intellectual disability, low

Edwards’ syndrome

also called trisomy 18, a condition that causes severe developmental delays due to an extra chromosome 18. Patients may experience abnormally small head, absence of one or both testes, birth defects with intestinal organs outside of the body, failure to thrive, low birth weight, short stature, or underdeveloped jaw and others.

Klinefelter Syndrome

Also called XXY syndrome, males born with XXY syndrome may have low testosterone and reduced muscle mass, facial hair, and body hair. Common symptoms may include ADHD predominantly inattentive, delayed puberty, flaccid muscles, infertility, low

Turner’s Syndrome

also called gonadal dysgenesis, when a female is born with only one X chromosome. Symptoms include short stature, delayed puberty, infertility, heart defects, and certain learning disabilities.