genetics

• chromosome: DNA wrapped around a protein
• Gene: section of DNA that codes for a protein/trait
• Autosome: all chromosomes besides sex-chromosomes
• sex chromosomes: X and Y, determine the sex of an individual, total of 23
• Diploid: normal number of chromosomes in a somatic (body) cell, 2 of each type
• homologus chromosomes: chrom. pairs that are the same length and genes, but might code different traits
• gamates: sex trait, contains half the DNA
• Myosis: cell division that reduces the number of chromosomes by half
• zygote: baby/diploid
• Allele: different versions of a gene
• Dominant allele: if present, it will always be expresed
• Recesive allele: trait hidden in presence of dominate allele.
• Genotype: genetic makeup; two alleles (PP,Pp, pP, or pp)
• Homozygous geneotype: two of the some alleles (PP, pp)
• heterozygous geneotype: one of each allele (Pp)
• Phenotype: physical appearance of an organism
• Linked genes: located near each other on the same chromosome, tend to be inherited together (doesn't follow Mendel's law of independent assortment
• Incomplete dominance: one allele doesn't completely mask the other, and neither has dominant control
• Co dominance: inheritance pattern in which both alleles in a heterozygote contribute to the phenotype
• Achondroplasia: AA= basically dead, Aa= dwarf, aa=normal height
• Multiple alleles: one trait can be controlled by 2 or more alleles
• Multiple genes: one phenotype is controlled by two or more genes (on multiple chromosomes)
• X-linked genes: genes located on the X chromosomes, more common in males (ex. color blindness and hemophilia)