Vocabulary
Define phenotype.
An organism's physical appearance or visible traits that are expressed
Write a heterozygous genotype.
Aa
Who is known as the father of genetics?
Gregor Mendel
Describe incomplete dominance?
The offspring receives a blended trait from its parents if it's genotype is heterozygous.
Describe codominance.
When both dominant alleles from a gene are expressed when the offspring is heterozygous
Define genotype.
The gene combination for a trait. Written using capital and lower case letters.
The passing of traits from parent to offspring is called ____________.
heredity
In a heterozygous genotype, which allele is expressed?
dominant
One purebred black dog (BB) is bred with a purebred white dog (WW). The cross is incomplete dominance. What will the babies look like? (BW)
gray fur
One purebred black dog (BB) is bred with a purebred white dog (WW). The cross is co-dominant. What will the babies look like? (BW)
both white and black
Write a homozygous recessive and homozygous dominant genotype.
aa - homozygous recessive
AA - homozygous dominate
B = Brown
b= Blue
Cross the following parents to show the offspring.
BB x bb
All genotypes = Bb, Brown
When is a recessive allele expressed?
In the absence of a dominant allele
A red flower (RR) and a white flower (WW) are crossed. What will the offspring look like if the cross is incomplete dominance?
Pink
Which of the blood types is codominant?
Blood Type AB
A diagram used to show the genetic possibility of offspring is called a __________________.
Punnett Square
B = Brown eyes
b = blue eyes
Cross a heterozygous father and a mother with blue eyes. Show all work.
Bb x bb
Results:
Bb = 2/4 50%
bb = 2/4 50%
Describe the genotype "RR" in two different ways.
Pure dominant
Homozygous dominant
If a BB is brown fur and WW is white fur, what would a palomino horse look like if this where an incomplete dominance trait? What would the palomino horse's genotype be?
tan BW
Blood type AB is crossed with a parent with Blood Type BO. What are the possible blood types of the offspring.
AB
BB
AO
BO
What is an allele? What two forms can it take?
Gene for a specific trait. Can be dominate or recessive.
B = Brown eyes
b = blue eyes
Cross two heterozygous parents. Write the possible genotypes and phenotypes.
Bb x Bb 75% brown eyes 25% blue eyes
50% 2/4 Bb
25% 1/4 BB
25% 1/4 bb
R = round
r = wrinkled
A pure recessive and pure dominant pea plant are crossed. Write the possible genotypic and phenotypic possibilities.
RR x rr
Rr 100%
100% Round
RW - 100% purple
A man with type O blood has a child with a woman who has Type AB blood . What are the possible blood types of the children. Show the Punnett Square work and the percentages.
Blood Type A
Blood Type B