Download Test Corrections for Genetics Test B Test corrections are available to

Test Corrections for Genetics Test B
Test corrections are available to those that completed the study guide. Each question will receive ½ credit toward the
test grade.
Missed any of 1-3, 5 or 6. Use the information in the question to write a summary of the why Protein synthesis is called
the central dogma and how the sequence of nucleotide bases (ATCGs) provide the code to make proteins. Provide two
examples of proteins.
#4 missed – describe the structure and function (2-3 sentences) of DNA and complete the complementary base pairing
below.
If a section of DNA has the following order of bases, what would the complementary DNA strand be?
DNA strand: T
A
C
T
G
T
G
G
C
A
A
A
Other strand
#7 missed – write the amino acids for the following mRNA sequence. Define codon and describe which molecule the
codon is read from.
AUG-
CCC-
GGC-
#8 missed – describe the structure of DNA compared to RNA and the different nucleotide bases present in DNA versus
RNA.
#9 missed- define meiosis and describe how meiosis contributes to inheritance of traits (2-3 sentences)
#10 or 11 missed – define how nondisjunction occurs during meiosis and how that contributes to chromosomal disorders.
Provide three examples of chromosomal disorders and the extra (or missing chromosomes).
#12 missed – define mutation and provide examples of types of mutations and causes.
Extra Credit: What is angiogenesis and how does it contribute to cancer metastisis?
#13 missed – review the process of transcription and translation and write a summary about the intent of both and the
overall goal.
Missed 14, 15, 16, 17 or 18.
Define mutation and explain ways DNA can become mutated. Define the three main types of mutations, - insertion,
deletion, and substitution. Show an example of each. Explain why a substitution is classified as a point mutation
and why an insertion or deletion is a frameshift mutation.
Missed 19, 20, 21 or 22, or 25
Below show the alleles (individual forms of genes) for the two individuals. The male has brown eyes with a genotype
of Bb and the female has blue eyes with alleles bb. The chromosomes represent autosomes (non-sex chromosomes).
What alleles can the female donate to offspring – only
What alleles can the male donate to the offspring -
or
or
Draw the exact copy for each chromosome showing attachment at the centromere. Define sister chromatid and
explain how the above drawing represents the tetrad formed after the DNA is replicated during meiosis.
Do the Punnett square for the couple above.
What are the genotypic ratios?
What are the phenotypic ratios?
.
Missed 23, 24, 30 -Define codominance, incomplete dominance, and codominance. Provide an example of each
type. Do the following crosses
1. In guinea pigs, neither yellow (Y) or (W) white color dominants. They blend, forming a cream color with the
heterozygous mix. Cross a cream-colored guinea pig with a yellow one. Give the genotypic and
phenotypic ratios.
Cross
5. In four o’clock plants, the flowers may be white or red in the purebred plant (homozygous). In the hybrid
(heterozygous) plant, the flowers are pink. Cross two pink flowers and give the genotypes, phenotypes
and ratios. Let R = red and W= white. CROSS
Ratios:
Genotypic:
Phenotypic:
Codominance
In cases of codominance, both alleles are dominant and both are expressed evenly. For example, a cross
between a white flower (W) and a purple flower (P) would produce a purple and white spotted flower.
6. In some chickens, the gene for feather color is controlled by codominance. The allele for black is B and the allele for
white is W. The heterozygous phenotype is known as erminette (black and white spotted). Show a cross between a
Black and a White chicken (two erminette). CROSS
a) What is the genotype for black chickens? ____
b) What is the genotype for white chickens? ____
c) What is the genotype for erminette chickens? ____
7. In shorthorn cattle, when a red bull (RR) breeds with a white cow (WW), all the offspring are roan—a spotted, red
and white or milky red color. What offspring are expected from mating a roan bull and a roan cow? Show the
Punnett Square, phenotypes and genotypes.
Cross
Genotypic Ratio:
Phenotypic Ratio:
Missed 26 - Define homozygous dominant, homozygous recessive, and heterozygous. Do the following cross.
A homozygous recessive blue eyed individual has a child from a heterozygous brown eyed
individual. Show the cross and the genotypic and phenotypic ratios.
Missed 27- Draw a representation of XX chromosomes and an XY with the allele for hemophilia
(h) mutation attached to the second X of the female and the male X. Attach a normal hemophilia (H) alllele to the
first X of the female. Explain why it take two alleles for a female to inherit hemophilia and only one allele for a
male to inherit.
Missed 28 and/or 29, – Define autosomal recessive and autosomal dominant. How are these different from sexlinked? Do the cross below.
Cystic fibrosis is an autosomal recessive genetic disorder that affects the lungs and the digestive system. A man
and a woman marry and have a child with cystic fibrosis. Neither the man nor the woman have cystic fibrosis.
(What are the genotypes of the couple?
Dad
Mom
Complete a Punnett square and show your work. What are the chances of their offspring having cystic fibrosis?
Missed 31 and 32- Examining Karyotypes – Examine the karyotypes below.
Define autosomeDefine- sex-chromosomes
Sex- chromosomes of femalesSex- chromosomes of males-
1. Circle the autosomes
2. Underline the sex chromosomes
3. What is the gender of this person?
4. How can you tell?
5. What if it has XY- then what gender?
6. Draw in a chromosome for down sydrome.
7. Draw in a chromosome for edward syndrome.
Missed any part of 33 Step 1 or Step 2, or step 3 – complete all parts.
Do the following crosses for sex-linked traits
Define genotype:
Define phenotype:
1. A colorblind female marries a man with normal vision. (not colorblind). Show the punnett square and the
genotypic and phenotypic ratios.
2. Draw a pedigree for the family above including the married couple- three children – one girl and one boy with
colorblindness and one girl without.
3. A woman marries a man and they have three childlren, A girl named Kathy, a boy named Zane and another boy
named Isaac. Isaac has hemophilia. Draw the pedigree for this family, including the maternal grandparents.
Label the genotypes or suspected gentypes for all.
Show the cross for the above couple and provide the genotypic and phenotypic ratios
The normal allele has been marked with a blue dye and the mutation allele has been marked with a purple dye. The
electrophoresis results are shown below for each of the children and the unborn baby. See the following results below.
Label the charges and use an arrow to show the direction of DNA movement. The mother is a carrier for Duchenne
Muscular Dystrophy and the father is normal. They are curious to determine the genotypes of the offspring. Their DNA
is collected and run through a process called gel electrophoresis. List the results below.
Girl # 1 genotype
Girl #1 phenotype
Girl #2 genotype
Girl #2 phenotype
Boy #1 Genotype
Boy #1 phenotype
Extra Credit Unborn baby possible
Genotypes
Unborn baby possible Phenotype
a. Is DNA positive or negative?
Step 3 Label the circles on the corner of the electrophoresis with positive (+) and negative (-). Label the direction of
DNA movement.
b. Describe how gel electrophoresis works.
c. Explain why the purple band moved further into the gel than the blue band?
d. The location of the mutation allele in the gel electrophoresis suggest it is a
a. insertion
b. mutagen
c. substitution
d. deletion
Step 4: Use the results and the information above to label genotypes (and possibilities) and shade affected and carriers.