Download Genetics and Punnett Squares

Bellwork: What is the difference
between a dominant gene and a
recessive gene?
 Cells
are the basis of genetic activity
 Basic
structure of all living things
 All
plant and animal life begins as a
single cell
 The
nucleus contains pairs of
chromosomes on which genes rests at
specific locations
 Animal
growth and reproduction takes
place via cell division
 Mitosis: Simple
 DNA
cell division for growth
replicates and then is passed on to
each divided cell
 Meiosis: Cell
division that results in the
formation of gametes or sex cells
 Chromosomes
divide and one is passed
on to each new cell
A
chromosome from each parent
combines with the chromosome from the
other parent and genetic recombination
occurs
 Genes-
units of genetic material
 Genes
occur at specific locations on
chromosomes
 In
pairs of genes the genes may be alike
or different
 Homozygous-
pairs of genes that are
alike
 Heterozygous-
pairs of genes that are
different
 When
two genes in a pair are different,
one usually expresses itself while the
other does not …..dominant vs. recessive
 Genotype-
the actual configuration of
genes
 Phenotype-
animal
Physical appearance of the
 Eye
Color- Brown Dominant; Color
Recessive
 Tongue
rolling- Can roll Dominant;
Cannot Roll; Recessive
 Thumbs-
Straight Thumb Dominant;
Curved Thumb Recessive
2
Individuals one can roll their tongue
and the other cannot
 Male
can roll his tongue and has a
heterozygous genotype Rr
 Female
cannot roll her tongue and has a
homozygous genotype rr