Bio 191 exam BEST STUDYING MATERIAL
WITH VERIFIED ANSWERS LATEST VERSION
UPDATE 2024-2025 WITH 100+ QUESTIONS
Through a microscope, you can see a cell plate beginning to develop across the middle of a cell
and nuclei forming on either side of the cell plate. This cell is most likely ________.
- CORRECT ANS-a plant cell in the process of cytokinesis
Exposure of zebrafish nuclei to cytosol isolated from eggs at metaphase of mitosis resulted in
phosphorylation of NEP55 and L68 proteins by cyclin-dependent kinase 2. NEP55 is a protein of
the inner nuclear membrane, and L68 is a protein of the nuclear lamina. What is the most likely
role of phosphorylation of these proteins in the process of mitosis?
- CORRECT ANS-They are involved in the disassembly of the nuclear envelope.
what is true about human X chromosomes?
- CORRECT ANS-It carries genes that influence an individual's biological sex.
Asexual reproduction occurs during which of the following processes?
- CORRECT ANS-mitosis
describe a major difference between mitosis and meiosis I in a diploid organism
- CORRECT ANS-Sister chromatids separate in mitosis, while homologous pairs of chromosomes
separate in meiosis I.
A cell has completed meiosis I and the first cytokinesis, and is just beginning meiosis II. Describe
its genetic contents.
- CORRECT ANS-It has half the amount of DNA as the cell that began meiosis.
,During which of the following phases of meiosis do homologous chromosomes separate? -
CORRECT ANS-anaphase I
what happens at the conclusion of meiosis I?
- CORRECT ANS-Homologous chromosomes of a pair are separated from each other.
A (hypothetical) diploid organism has different genes that control wing length and wing color.A
female of this species with short blue-colored wings has a chromosome pair with two short-
wing alleles and a second chromosome pair with one blue-wing allele and one orange-wing
allele. The eggs from this individual will have which of the following combinations of alleles? -
CORRECT ANS-1/2 of the eggs will have alleles for short blue-colored wings and ½ will have
alleles for short orange-colored wings
For a species with a haploid number of 23 chromosomes, how many different combinations of
maternal and paternal chromosomes are possible for the gametes based on the independent
assortment of chromosomes during meiosis?
- CORRECT ANS-about 8 million
Albinism is a recessive trait where an individual does not produce the pigment melanin. A man
and woman who both produce melanin have one child out of three who has albinism. What are
the genotypes of the man and woman?
- CORRECT ANS-Both parents must be heterozygous.
What fraction of the offspring from a cross between two animals with the genotype AaBbCc are
expected to be homozygous recessive for the three traits?
- CORRECT ANS-1/64
In some parts of Africa, the frequency of individuals who are heterozygous for the sickle-cell
anemia allele is higher than the frequency in North America, presumably because this reduces
the frequency of malaria. What is the relationship related to?
- CORRECT ANS-Darwin's theory of natural selection
,Albinism is a recessive trait where an individual does not produce the pigment melanin. A man
and woman both produce melanin, but both have one parent with albinism. What is the
probability that their first child will have albinism?
- CORRECT ANS-1/4
In a cross of individuals who both possess this genotype, AaBbCc, what proportion of the
offspring is predicted to have the genotype, AABBCC?
- CORRECT ANS-1/64
Having polydactyly (extra digits on hands and feet) is a dominant trait. A man has polydactyly.
His wife and oldest daughter do not have polydactyly. The couple's second child has
polydactyly. What is the probability that their next (third) child will have extra digits?
- CORRECT ANS-1/2
In a certain species of diploid fish a single gene controls skin color. Researchers have found four
different alleles of this gene within the fish population. How many different gamete genotypes
are possible in an individual of this species?
- CORRECT ANS-2
In human blood types, Rh positive is a trait that shows simple dominance over Rh negative. The
Rh phenotype is recorded by stating "positive" or "negative" after the individuals ABO blood
type. A woman who has blood type A positive has a daughter who is type O positive and a son
who is type B negative.What is the possible phenotype for the father?
- CORRECT ANS-B positive
describe how an individual with genotype AaBbCCDdEE can make haploid gametes with
different genotypes
- CORRECT ANS-the inheritance of a particular copy of one chromosome does not affect the
inheritance of a different chromosome
, define one genetic map unit –
CORRECT ANS-the physical distance between two genes that results in a 1% frequency of
recombination
In birds, sex is determined by ZW chromosome inheritance. Males are ZZ and females are ZW.
Within pigeon populations there is a recessive, Z-linked allele that is lethal in embryos. What is
the expected sex ratio in the offspring of a cross between a male that is heterozygous for the
lethal allele and a wildtype female?
- CORRECT ANS-2:1 male to female
A recessive allele on the X chromosome is responsible for red-green color blindness in humans.
A woman with normal vision whose father is color blind has children with a color-blind male.
What is the probability that this couple's first son will be color blind?
- CORRECT ANS-1/2
What is the greatest benefit of using a testcross to determine an unknown genotype? -
CORRECT ANS-A progeny's phenotype reflects the contribution from the heterozygous parent.
When Thomas Hunt Morgan crossed red-eyed F1 generation flies to each other, the F2
generation included both red- and white-eyed flies, but all the white-eyed flies were male.
explain Morgan's result
- CORRECT ANS-The gene involved is located on the X chromosome.
A man with normal vision who is a dwarf due to achondroplasia has children with a woman with
colorblindness who is of average height. Dwarfism caused by achondroplasia is autosomal
dominant, and red-green color blindness is X-linked recessive. What proportion of their
daughters are expected to be color-blind with achondroplasia?
- CORRECT ANS-0
Abnormal chromosomes are frequently found in malignant tumors. Errors such as
translocations may place a gene in close proximity to different control regions that could result
in ?
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller qualityexamshut. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $24.99. You're not tied to anything after your purchase.
