Genetics Test 1 Study Guide
1. Complete the chart below comparing mitosis and meiosis
Mitosis
Meiosis
Type of Reproduction
asexual
sexual
Type of Cell It Occurs In
Somatic (body) cells
Gametes (sex cells)
# of Cell Divisions
1
2
Haploid or Diploid?
diploid
# of Chromosomes in
Human Cells
# of Cells Produced
Genetic Info Identical to
or Different from Parent
Cell
haploid
23
46
2
4
different
identical
2. Write the correct steps of meiosis below:
Prophase 1
Metaphase 1
Telophase 2/
Cytokinesis
Anaphase 1
Anaphase 2
Telophase 1
Metaphase 2
Prophase 2
3. When does crossing over occur? Prophase 1
4. What is the purpose of crossing over? Genetic variation (differences in genes)
5. What are gametes? Sex cells (egg and sperm)
6. _ Genetics_ is the study of how traits/characteristics are passed from generation to
generation.
7. _ Mendel_ is known as the “Father of Genetics” due to his work studying pea plants.
8. List Mendel’s 3 laws and explain what they are.
a.
Law of Dominance – if the dominant trait is present, it will be expressed
b.
Law of Segregation – alleles separate during meiosis
c.
Law of Independent Assortment – traits are inherited independently of one another
(Ex: having brown hair will not guarantee having brown eyes)
9. What is the difference between dominant and recessive? Dominant – always expressed
when present; Recessive – can be masked by dominant trait
10. Different forms of the same gene are known as _ alleles__.
11. The actual inherited combination of alleles (Bb, BB, or bb) is known as the offspring’s
_ genotype__.
12. The organism’s appearance is known as its _phenotype__.
13. Identify the difference between homozygous and heterozygous, then give an example of
each. Homozygous –having two of the same alleles (ex: AA, aa); heterozygous – having
different alleles (ex: Aa)
14. Refer to the list of pea plant traits to complete the table below:
Yy
purple
ww
TT
round
yellow
tt
Ii
II
15. Complete the Punnett Square to complete the F1 generation.
Ww
Ww
Ww Ww
a. What color are the flowers in the F1 generation? Purple
b. What is the dominant trait? Recessive trait?
Purple
white
c. How does this cross demonstrate Mendel’s principle of dominance? The dominant
trait (purple – W) is present, therefore, it is expressed
16. Complete the Punnett Square to show the F2 generation.
WW Ww
Ww
a. What is the ratio of purple to white flowers? 3:1
ww
b. What percentage of the offspring are purple? White?
75%
25%
c. What percentage of the offspring are WW? Ww? ww?
25% 50% 25%
17. Cross a tall homozygous dominant plant with a tall heterozygous plant and provide the
genotype and phenotype ratios.
T
T
TT
T
TT
Genotype: 2:2 = 1:1 (50% TT, 50% Tt)
Phenotype: 4:0 (100% tall)
t
Tt
Tt
18. _ Codominance__ occurs when two dominant traits are expressed but do not blend
together.
19. _ Incomplete dominance__ occurs when two dominant traits are expressed and blend
together.
20. Type AB blood is an example of what kind of dominance? codominance
Old Material
21. Identify the types of mutations below:
deletion
Insertion/addition
substitution
22. Using the strand of DNA, transcribe the RNA strand and translate what the amino acids
should be.
DNA:
TAC
AAT
mRNA:
AUG
UUA
tRNA:
UAC
AAU
TCC
CGA
GTC
ATC
AGG
GCU
CAG
UAG
CGA
GUC
AUC
UCC
Leu.
Arg.
Glu.
Ala.
Amino Met.
Acid:
(Hint: Use mRNA and Amino Acid Chart to find amino acid)
23. Complete the chart comparing DNA and RNA below.
Structure/
Shape
Bases
Type of
Sugar
Location
DNA
RNA
Double helix
single stranded
A, T, C, G
A, U, C, G
Deoxyribose
Ribose
Nucleus
cytoplasm
mRNA – carries
message outside
of nucleus
rRNA – reads the
message on mRNA
Use
Contains genes
and instructions
for making
proteins
tRNA – carries
amino acids to
mRNA
Stop
24. Label the following organelles on the cells below and identify which is a plant cell and
which is an animal cell. Then write the function of each organelle where you labeled it on
the cells.
a. Nucleus
d. Cell membrane
g. Vacuole
b. Ribosomes
e. Cell wall
c. Mitochondria
f. Chloroplast
ANIMAL CELL
Cell membrane – controls what
enter
Mitochondria – provide energy
Ribosomes – make proteins
Cell membrane – controls what
enters/leaves the cell
s/leaves the cell
Nucleus – controls the cell
PLANT CELL
Vacuole – stores materials
Chloroplast – performs
photosynthesis
Ribosomes – make proteins
Cell wall – provides structure
and support for the cell
Cell membrane – controls what
enters/leaves the cell
Mitochondria – provide energy
Nucleus – controls the cell