Genetics

The study of heredity. The passing of physical biochemical physiologic traits from biological parents to their children

Contains chromosomes, basic units of inheritance, composed of DNA

DNA subunit or nucleotide contains (3)

Nitrogenous base has four components

Single carbon nitrogen ring pairs

Double carbon nitrogen rings called purines

Provides the code for all body proteins

Composed of one or more polypeptides

Composed of 20 amino acids

Sequence of three bases that directs production of amino acids

Amino acid that Stops the production of protein (2)

Untwisted and unzipped single strand that acts as a template or guide

Pairs with complementary basis (a-t and c-g), adds new nucleotides and proofs the new protein, if not correct the nucleotide is excised and replaced.

Proof reader to make sure nucleotide is replicated correctly. Most important protein

Any inherited alteration of genetic material

One base pair is substituted for another, changes amino acid sequence, may or may not cause disease or problem (2 names)

Involves insertion or deletion or one or more base pairs to DNA Molecule

Agents like radiation and chemicals the increase the frequency of mutations

The first 22 of the 23 pairs of chromosomes in males and females. 2 members are identical / homologous (same)

23rd chromosome. Makes up male and female

Female homologous pair

Male nonhomologous pair

Length and centromere location determine ordered display of chromosomes. Picture of all the chromosomes. Ordered display of chromosomes

Involves a loss or gain of chromosomes resulting in specific karyotype

Loss of one chromosome

Gain of one chromosome

Normal number of chromosomes

Does not contain multiples of 23 chromosomes

Error in homologous chromosomes

Trisomy 21. Increased risk for congenital heart disease, respiratory infections, leukemia. Mental challenged, low nasal bridge, epicanthal folds, protruding tounge, flat low set ears, poor muscle tone. 1 out of 800 births. Risk increases with maternal age.

Broken chromosome or loss of DNA

Interchange of portion of one chromosome to another chromosome

Excess of chromosome material

Occurrence of 2 breaks of chromosome, followed by reinsertion of the missing fragment at its original site but inverted order

Sex chromosome missing, resulting in 45 X. No Y chromosome, affects only females. Short stature, webbed neck, shield like chest, underdeveloped breast, and imperfectly developed ovaries, sterile. IQ normal, give estrogen to develop secondary sex char

Have at least 2 X and 1 Y chromosome in each cell. Results in 47, XXY male appearance. Sterile. Small testes. Breast may develop. Sparse body hair. Long limbs

Mechanisms where individual's set of paired chromosomes produces traits.

First defined genetic principles by working with garden peas

Trait caused by single gene

Each gene occupies position on chromosome known as...

Different forms of genes located at the same locus on the chromosome

2 or more alleles that occur with appreciable frequency

At any given locus in a _____ cell, an individual has 2 genes, one from each parent

Dominant gene effects mask the recessive gene

Expressed only when it is present in two copies

Refers to individual genetic makeup

Outward expression and is results of genes and enviroment

Allele whose effects are observable is dominant Aa

Recessive allele to be expressed. Must exist in the form aa

Both ate heterozygote and dominant: AB blood group

Individual who has a disease gene but is phenotypically normal

Trait caused by autosomal dominant gene. 2 sexes exhibit the trait in equal proportions. Males and females are equally likely to transmit to offspring. No skipping of generations. If an individual has the trait then the parents must have it.

Affected ____ individuals transmit trait to half their children. All or none may be affected. Closely approaches half.

Outcomes for offspring of an unaffected father and a heterozygous unaffected carrier mother (most common)

Outcome for the offspring of an affected father and homozygous unaffected mother

Outcomes for the offspring of an affected father and heterozygous unaffected carrier mother

Trait that can occur in only one of the sexes

Trait that occurs significantly more often in one sex than in the other

Uses computer programs and stats for genetic counseling

Child born with autosomal dominant disease and no family history. New mutation

Percentage of individuals with specific genotype who also exhibit expected phenotype.

Individual who has gene for disease but do bot exhibit disease phenotype. Gene and the associated disease may be transmitted to the next generation.

Extent of variation in phenotype associated with particular genotype

Two examples of autosomal dominant inheritance

Males and females affected equally, consanguinity often present. Disease seen in siblings buy usually not in parents. 1/4 of offspring of carrier parents affected

Keeping it in same family. Cousins.

Four examples of autosomal recessive inheritance

Most sex linked traits are located on which chromosome?

Female must be homozygous and seldom affected. Either both parents affected of father affected and mom is carrier