Genetic crosses + heredity Flashcards
composition of chromosomes
protein and DNA
what are somatic cells
all the cells of an organism have the same no of chromosomes
gametes
haploid cells capable of fusion ie egg +sperm
what is the one exception to somatic cells in the human body?
egg or sperm/ gametes
what is a homologous chromosome
2 chromosomes that are similar size and have the same gene location
where are homologous chromosomes found
diploid cells
alleles
different forms of the same gene usually found in 2 forms: dominant and recessive
dominant
capital letter, masks the expression of a recessive allele
recessive
small letter, masked by a dominant allele
locus
position of a gene on a chromosome
genotype
genetic makeup of an organism
phenotype
physical appearance of an organism
progeny
offspring produced
homozygous
the 2 alleles of a gene are identical
heterozygous
the 2 alleles of a gene are different
incomplete dominance
neither allele, recessice or dominant masks the expression of the other
what is an autosome
a chromosome that controls features that are independent of whether the person is male or female
which chromosomes are female
XX
which chromosomes are male
XY
what are the consequences of the sex chromosomes
males determine the sex of a child
male to female ratio is 1:1
how many chromosomes are autosomes
22 pairs
law of segregation
inherited characteristics are controlled by pairs of factors. these alleles segregate at gamete formation, with only 1 member from each pair being found in each gamete
law of independent assortment
when gametes are formed either a pair of alleles is equally likely to combine with either of another pair of alleles
monohybrid
studying a single trait or characteristic
