Chromosomes
• Threadlike structures or granular chromatin during interphase
• In nucleus• Carry DNA• Form for mitosis• Displayed as a
karyotype
Gene• Part of chromosome
that controls the inherited traits
• One part of DNA• Located on a
certain place of the chromosome
• 1 gene = 1 trait• May work together• Also control
chemical processes of life
Chromosome Pairs
• Occur in pairs• One version from
each parent• One version of each
gene from each• 23 pair in humans• Usually similar in
size, shape, and genes (homologous)
Alleles
• Different versions of same gene
• Usually found at same location on the same chromosome
• At least 2; sometimes several
Examples of Gene Alleles
• Eye color – blue or brown groups
• Then divided:• Blue = blue, green,
gray• Brown = gold,
brown, black• Amount of melanin