USC bridge Nurs 500 3.3 Chromosomes and Genetics
Chromosomes and Genetics- the study of heredity
diploid chromosomal complement displayed in homologous pairs
the genetic information in a cell.
Genetic (DNA) makeup, represents two sets of genetic instructions- one from the egg and one from the sperm.
in the nucleus, is uncondensed lose and unwound, made of DNA histone proteins are wrapped around the DNA. Becomes condensed into the chromosome structure called a chromatid.
The ends of the Eukaryotic chromosomes, nucleotide sequences that don't encode proteins, protect the gene sequence from being lost. Cap the chromosomes to protect them from being degraded.
Aging cells have lost the ends of the telomere, when that happens the cell is destroyed.
Can make new telemeres
Chromosomes- Genes, allele, genotype, phenotype
Chromosomes- structures containing DNA that physically carry hereditary information, chromosomes contain genes.
Gene- DNA segments containing genetic blueprints for proteins that dictate the synthesis of the body's molecules.
Allele-A specific version of a gene. Matched pairs of genes one from each parent that interact to dictate that trait. Homogolous chromomes. May code for the same or for alternative forms of a given trait. Ie: hair.
genotype- a person's genetic makeup
phenotype- actual expressed properties, the way that genotype is expressed
when 2 alleles that control a trait are the same
when the two alleles are different.
Dominant vs recessive
when the allele masks or suppresses the expression of its partner it is dominant (shown by a capital letter). Recessive is the masked allele (shown by a lowercase letter). Recessive alleles must be present in double dose to be expressed also known as a homogenous condition.