unit 8.1- chromosomes and genes

what is inheritance

the transmission of characteristics from one generation to the next

what is a gene

a heritable factor consists of a length of DNA that determines a specific characteristics

how many chromosomes do humans have

46 (23 pairs)

what is a locus

the position of the gene on the chromosome

what are alleles

variations are caused by different forms of a gene

what types of chromosomes do people have

22 pairs are autosomes

1 pair are sex chromosomes

• XX in females

• XY in males

what are diploid cells

where each nucleus contains 2 sets of chromosomes

what cells are diploid

body cells

what are haploid cells

where the nucleus contains only one set of chromosomes

what types of cells are haploid

gametes

• in males → spermatoza

• in females → ovum