____.) In a diploid organism, what are different versions of the same gene called?
allele

____.) Consider the following situation: A certain species of tulip can be grown in two varieties of color based on one single gene. The pure breeding flower is blue, BB, and will always produce blue flowers because it has only the gene for blue flowers. The other color that these tulips can be is white, bb, which can produce white plants only if bred with other white tulips or tulips with an allele for white flowers.
a. Is BB homozygous or heterozygous? Dominant or recessive?
homozygous dominant
b. What about bb?
homozygous recessive
c. Some hybrid tulips are produced from certain crosses that have the genotype Bb. Are these homozygous or heterozygous? Why? What color will these tulips be?
heterozygous because there are 2 different alleles represented; blue

____.)
a. What is the term used to express the appearance or expressed traits?
phenotype
b. What is used to describe the actual genetic make-up behind these expressed traits?
genotype

____.) Gregor Mendel’s work with peas allowed him to reveal some important observations in genetics. Identify these observations from the descriptions below.
a. the alleles of one gene will separate into gametes independently of alleles on another gene = Law of Independent Assortment
b. traits are passed on to the offspring from the parents = Law of Inheritance

____.)
a. What is the term used for the normal phenotype for a character?
wild type
b. What are traits that are deviations from this normal phenotype?
mutant

____.) What is the term for a cross that tracks the inheritance of a single character? What about two characters?
monohybrid, dihybrid

____.) A pure bred black male mouse (BB) is mated with a pure bred white female mouse (bb) of the same species.
a. What will be the gametes produced by the black male?
B
b. What will be the gametes produced by the white female?
b
c. Create a Punnett square to show the potential offspring of this cross.

d. What are the genotypes and corresponding phenotypes each of the possible offspring?
Bb, black
e. What are the genotypic and phenotypic ratios of this F1 generation?
All Bb, black
f. Now cross two of the offspring in the F1 generation (F1 Cross). ___Bb____ X ___Bb____
g. What are the gametes that one of these offspring in the F1 generation can produce?
B or b
h. Create a Punnett square for this monohybrid cross.

i. List the genotypic and phenotypic ratios for this F2 generation.
1BB:2Bb:1bb, 3 black : 1 white
j. Will the genotypic and phenotypic ratios always coincide? Why or why not?
No because of masking of traits

____.) Now consider a population of pea plants with the ability to have green or yellow seeds.
a. If a pure-breeding yellow and pure-breeding green strain are crossed, and all of the progeny are green, what does this indicate about the expression (dominance/recessiveness) of the yellow and green alleles?
The two strains were both pure-breeding and could only produce gametes containing one type of allele. All progeny would be Gg. If all are green, then the green allele must be dominant to the yellow allele.
b. Let’s assume that G is the dominant allele and g is the recessive allele, Remembering that green is dominant, is it possible to deduce the genotype of a pea plant at the color gene if the color of the peas are green? Why or why not?
No, because a green plant could be homozygous GG or heterozygous Gg.
c. If a green plant is encountered, what can be done to deduce the genotype of the plant and what does this type of cross involve?
testcross - involves crossing dominant phenotype of unknown genotype with a homozygous recessive individual
d. If a green plant is crossed with a pure-breeding yellow strain, and some of the F1 generation are yellow and some are green, what is the genotype of the original green plant?
The original is heterozygous Gg.

____.) Many diseases and disorders are known to be inherited traits. One example of this is sickle-celled anemia, a blood disease that causes red blood cells to deform to a sickle shape causing clotting and other problems. A married couple has just had a child and that child has sickle-cell anemia. If neither the nam nor the woman have the disease, how is this possible? What is the overall probability that their children will get the disease?
It is a recessive disease and both parents are carriers, 25% chance

____.) In adddition to color, genetics controls for the height of a tulip’s flowers. Imagine that a blue, short plant (BBSS) was crossed with a white, tall plant (bbss).
a. What would be the potential gametes of each plant?
BS and bs
b. Use these gametes to set up a Punnett square and determine your offspring.

c. What are the potential phenotypes of this F1 offspring?
blue and short
d. Now cross two of the offspring ( F1) dihybrids. ____BbSs___ X ___BbSs____
e. What are the potential gametes?
BS, Bs, bS, or bs

f. Create a Punnett square to determine your offspring.

g. What are the potential phenotypes and phenotypic ratios?
9 blue/short : 3 white/short : 3 blue/tall : 1 white/tall

____.)
a. What are the traits that are determined by genes on the X and Y chromosome?
sex-linked traits
b. Would it be possible for a father to pass a Y-linked trait to a female child? Why or why not?
No, since females would never have a Y chromosome.
c. From which parent do males receive X-linked traits?
mother
d. Colorblindness is an expample of an X-linked trait. Imagine a man is colorblind and his wife is homozygous normal. What will be the phenotypes and genotypes of the sons and daughters of this couple?

all children will be normal, both the females will be carriers

____.) A cross between a red rose (RR) and a white rose (rr) produced all pink offspring (Rr). Explain this phenomenon. What is it called?
incomplete dominance

____.)
a. What is the term used to describe the phenomenon of a person AB blood type?
multiple allelism
b. A man of blood type A marries a woman of blood type B. What are the possible genotypes of the offspring?
A, B, AB, O
c. If a man is needing a blood transfusion is of the blood group AB, which blood types could he be given?
A, B, AB, O
d. A hospital has possibly switched the babies of couple X and couple Y. Their blood groups are as follows:
X: A & O
Y: AB & B
Baby 1: AB
Baby 2: O

Which baby belongs to which couple?
Baby 1 belongs to Couple Y and Baby 2 belongs to Couple X.

____.) What is the major phenotypic difference between multiple allelism and incomplete inheritance?
multiple allelism expresses both traits while incomplete inheritance expresses new hybrids of traits

____.) Explain the difference between pleiotropy and polygenic inheritance and give an example of both.
pleiotropy - single gene affects many phenotypic characteristics (sickle-cell disease)
polygenic inheritance - 2 or more genes afect a single phenotype (skin pigmentation)

____.) A gene for curly hair cannot be expressed if a different gene in the same individual causes baldness. What is this an example of?
epistasis

____.) A pedigree is a family tree describing the occurrence of characteristics in parents and offspring across as many generations as possible. The circle represents a female while a square represents a male. A darkened symbol represents a person that expresses the phenotype of choice. Look at the following pedigree and answer the questions. Darkened symbold represent a certain disease.

a. Would you expect the allele that causes the disease to be dominant or recessive?
recessive
b. Is the disease most likely sex-linked? If so, which sex chromosome?
yes, X
c. Use the information you just deduced to label the genotype of each individual in the pedigree.