Chapter 1 - Genes And Heredity Flashcards
Chromosomes
Strands of genes, come in pairs
Gene
Unit of heredity; portion of DNA, chromosomes coded for specific protein; every cell contains the same genes; expression determined by environmental factors (molecules within and nearby the cell); maintain structural identity from one generation to another
DNA
Double stranded molecules; strand of DNA serves as template for synthesis of RNA; contains 4 “bases”: adenine, guanine, cytosine, thymine
RNA
Single strand chemical; messenger RNA template for synthesis of protein molecule; amino acids form basis for proteins; proteins become part of body’s structure, others are enzymes
Enzymes
Biological catalysts that regulate chemical reactions in the body
Protein synthesis
-ase means enzyme = protein; after proteins made, some are stored, some transported; contribute to structure and function of cell; DNA transcribed by mRNA, mRNA translated in ribosomes, proteins made from joining amino acids together
Homozygous
Identical pair of genes of 2 chromosomes
Heterozygous
Unmatched pair of genes on 2 chromosomes
Mutation
Affects single amino acid, RARE change in a SINGLE GENE
Recombination
New COMBO OF GENES not in either parent that occurs ALL THE TIME
Epigenetics
Studies change in gene expression without modification of DNA sequence; some genes only active at certain point in one’s life (pregnancy); these are particularly susceptible to epigenetic modification
Dominant gene
Shows strong effect in homozygous or heterozygous condition
Epigenetic effects
Histone proteins bind bNA into a shape, like string wound around a ball; for gene to be activated, histones must loosen “grip” on bNA; one’s environment can modulate intracellular environment
Recessive gene
Only shows effect in homozygous condition
Autosomal genes
All other chromosomes except sex-linked genes
