Lecture 1 Flashcards
what is human genetics
the study of human variation
medical genetics
the study of genetic disease in humans
clinical genetics
a medical specialty which deals with families affected by or at risk of genetic disease
what are the two major foundations of modern genetics
- Darwins theory of evolution
- Mendel’s laws of heredity
Mendel’s Laws
- law of uniformity
- law of segregation
- law of independent assortment
homozygote
an organism that carries two identical alleles for a particular gene
explain the law of uniformity
when 2 homozygotes for different alleles are crossed, all of the F1 offspring are identical and heterozygous
during the formation of gametes, the two alleles (variants of a gene) for each trait separate
from each other so that each gamete receives only one allele for each trait. As a result, offspring inherit one allele from each parent.
explain the law of segregation
each individual possesses 2 genes for each characteristic only one of which can be transmitted at any one time
explain the law of independent assortment
members of different gene pairs segregate to offspring independently of one another
eugenics
the improvement of a population genetic constitution by selective breeding
how are genes carried
genes are carried by chromosomes which are present in the nucleus of every cell
mitosis
form of replication in all non-gonadal cells.
cell replicates to form two identical copy cells, each with the same number of diploid number of chromosomes
meiosis
form of cell division which produces gametes
in humans this form of division produces 23 chromosomes gametes from 46 chromosomes parent cells
what are the stages of mitosis
interphase: DNA replication
prophase: chromosomes condense
metaphase: chromosomes align in center and attach to spindle
anaphase: move along spindles to opposite poles
telophase: the divides into two daughter cells
at what stage is best for looking at the chromosomes
metaphase
