Download Genetic Exam Study Guide

Genetics Study Guide
1) Define the Parental generation, the F1 generation and the F2 generation.
2) What process in the human life cycle results in the production of gametes?
3) Define genotype and phenotype. Explain how they are different and how they relate to each
other.
4) Define the terms heterozygous, homozygous, hybrid, purebred, dominant and recessive.
5) Know the difference between monohybrid crosses and dihybrid crosses. How many traits are
crossed in each?
A. Yellow is dom over pink, using Mendelian genetics, cross a heterozygous yellow flower (Y) with a
pink flower (y). Create a monohybrid Punnett square to solve the problem. What percentage of
the offspring will have the genotype Yy ? What percentage will have the pink flower phenotype?
Find the genotypic and phenotypic ratios.
B. Using Mendelian genetics, cross a heterozygous dom tall (T) and purebred blue (B) pea plant
with a short (t) and green (b) pea plant. Create a dihybrid Punnett square to solve this problem
(remember you must FOIL this time). What percentage of the offspring will be short AND blue and
what percentage will have the genotype TtBb? Find the phenotypic and genotypic ratios.
6) What is the specific goal of meiosis I and meiosis II?
7) What is the term that describes a pair of chromosomes of the same kind, that come from mom
and dad?
8) Describe the difference between somatic cells and gamete cells. Which is haploid and which
is diploid? How many chromosomes do somatic cells have? How many do gamete cells have?
9) Fertilization results in what kind of cell? Haploid or diploid? Will it be genetically unique?
10) The diploid number of chromosomes in human is? The haploid number of chromosomes in
humans is?
11) During which stage of meiosis does crossing over occur?
12) Mitosis results in two ________ cells, while meiosis results in _______ haploid cells.
13) Does Crossing-over occur in both meiosis I and meiosis II?
14) Sex cells, sperm cells, and egg cells are all examples of what kind of cells?
15) Color Blindness is an example of what kind of trait?
16) Define the Law of Dominance.
19) Define the Law of Independent Assortment.
20) Define the Law of Segregation.
21) A modifier gene that controls another gene usually results in what kind of trait? Give an example.
22) The study of how traits are passed down from generation to generation is called?
Form B
23) Different forms of a gene are known as? How are they represented in breeding experiments? How
many are needed to show a single trait?
24) Suppose a mouse is homozygous for alleles that produce black fur and homozygous for alleles of
a gene that causes albinism. What color fur will the mouse have?
25) If we cross two pink flowers and 50% of the offspring are pink, 25% are red and 25% are white,
what type of inheritance pattern is this?
26) A trait that requires many genes to be expressed is known as?
27) What is the purpose of meiosis?
28) The term that describes an organism that does not express the phenotype of a certain gene but
can still pass the gene on to its offspring is called?
29) When an organism has two alleles that are different but that code for a single trait, the organism is
called what?
30) What is the phenotypic ratio of a monohybrid cross between two heterozygous parents?
31) A woman who is colored blind will have which type of genotype? (When using “B” and “b” for
alleles variations.)
32) A plant that is homozygous for red flowers is crossed with a plant that is homozygous for white
flowers. In the case of co-dominance, the flowers of the offspring will be?
33) Define genes.
Form B
34) Mendel was known as the “Father of Genetics” because he developed what?
35) What will the sex chromosomes of a woman look like? What about a man’s?
Use the pedigree shown to answer questions #36-39:
Ash
36) Is this trait autosomal or X-linked and why?
37) Is this trait dominant or recessive and why?
38) In the pedigree, shade in any and all individuals who must be carriers for this pedigree to
make sense.
39) Properly label the generations on the pedigree. How many generations are portrayed in
the pedigree? Which generation is Ash in?
40) Draw and label each phase of meiosis and be sure to accurately depict crossing over.
WRITE OUT ALL YOUR QUESTIONS AS YOU STUDY!