Download Reviewing Key Concepts

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Reviewing Key Concepts
Short Answer On the lines provided, answer the following questions.
1. What is probability and how is it used in genetics?
Probability is the likelihood that a particular event will occur. The way in which alleles segregate is
completely random like a coin flip. The principles of probability can be used to predict the outcomes of
genetics crosses.
2. How are Punnett squares used in genetics?
Punnett Squares can be used to predict and compare the genetic variations that will result from a cross.
Reviewing Key Skills
3. Problem Solving If a heterozygous plant for seed color (Rr) is crossed
with a homozygous recessive plant (rr), what is the probability of each
seed color being produced? Explain your answer using a Punnett
square.
The probability will be ½ for each seed color.
4. Comparing and Contrasting How are homozygous and
heterozygous genotypes for a particular trait in plants different?
Give an example of a genotype for each.
Homozygous genotypes mean the plant has 2 of the same alleles for a trait (TT) or (tt). Heterozygous
means the plant has 2 different alleles for one trait. (Tt)
5. Applying Concepts How can two plants that have different
genotypes have the same phenotype?
If one plant is homozygous dominant (TT) and the other plant is heterozygous (Tt) they will have
different genotypes but the same phenotype.
Interpreting Graphics For questions 6 to 9, fill in the genotype and
percentage expected on the lines provided.
Tt
T
t
T
6.
TT
7.
Tt
t
8.
Tt
9.
tt
Tt
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