BIO 235 based on Exam 2

The histone core of a nucleosome includes two copies of each of the following EXCEPT:

H1

Which of the following statements is FALSE?

Translocations do not result in a loss or gain of genes and therefore never affect the phenotype of an organism.

Bacterial strains that can produce all necessary compounds and therefore grow on minimal media are called

prototrophs

Which aneuploidies have the highest survival rate in human embryos?

Aneuploidy of the sex chromosomes

The transfer of DNA from a donor cell to a recipient cell through a physical connection between cells is called

conjugation

Which of the following observations is evidence that DNA is double-stranded?

The amount of Adenine equals the amount of Thymine, and the amount of guanine equals the amount of cytosine.

A chromosome mutation that reverses the order of some genes on a chromosome is an example of a(n).

Inversion

Which of the following differences between heterochromatin and euchromatin is TRUE?

Heterochromatin has less transcription than euchromatin.

In American flamingos (Phoenicopters ruber), two genes, (Q) and (R), are linked and separated by 10CM. A female flamingo with the genotype Qq Rr is crossed with a qa rrmale. The femalesC mother was QQ rr. What is the probability that their first child will be Qq Rr?

5%

During the _____ cycle, bacteriophages insert their genomes into the bacterial chromosome and are inactive.

lysogenic

Most strains of cultivated bananas were created by crossing plants within and between two diploid species: Musa acuminata and Musa balbisiana. Plantains have two complete sets of chromosomes from Musa acuminata and one complete set from Musa balbisiana. Plantains are an example of which of the following?

Allotriploid

wo nonhomologous chromosomes have the following segments, where •represents the centromere:

Chromosome 1: ABCD• EFGH

Chromosome 2: KLM• NOPQR

What type of chromosome mutation would result in the following chromosomes:

Chromosome 1: A BCD • EFKL

Chromosome 2: GHM • NOPQR

Reciprocal translocation

You are investigating horizontal gene transfer between two strains of the fictional bacteria, Vernacoccus sakura. Strain A produces large, white colonies while strain B produces small, pink colonies. When you grow strains A and Bmixed together, you find some large, pink colonies. When you grow strains A and B in a u-shaped tube separated by a filter, you find some large pink colonies. This is evidence of what type of horizontal gene transfer?

Transduction

In a captive population of southern rockhopper penguins (Eudyptes chrysocome), the E locus controls eye color yith red eyes (e+) dominant to yellow eyes (e). The M locus controls crest size with large crest (m+) dominant to small crest (m).

You suspect that these two loci are linked. You perform a Chi-square Test of Independence on data

from a testcross and get a calculated ' = 0.0388. Which of the following is a correct conclusion?

Consult the chi-square table at the end of this exam and set alpha = 0.05.

The observed counts did not significantly deviate from expectations under the Principle of Independent Assortment. The loci are not linked.

A chromosome mutation that causes the loss of genes from a region on a chromosome

but does not affect the number of chromosomes is an example of a(n) _______.

Deletion

Which of the following statements about viruses is FALSE?

All viruses with RNA genomes insert their genome into the host genome.

Arabidopsis thaliana has 2n = 10 chromosomes, and a close relative Capsella rubella has

2n = 16. You have created a hybrid between them and suspect that it is an allotetraploid. If you are right, what possible chromosome numbers could the hybrid have?

26

Which of the following statements is TRUE?

All of the above statements are TRUE.

When the F factor inserts into the E. coli chromosome, the result is a(n) _____ strain

Hfr

Based on the following genetic map, the recombination frequency between locus C and

locus E is expected to be _____. Locus C and locus E are ____.

50%; on the same chromosome

In the lesser violescent fire beetle (Phanaeus incendia), the E locus controls body coloration with gold body (e+) dominant to red (e). The M locus controls mandible size with large mandibles (m+) dominant to small mandibles (m). You suspect that these two loci are linked and perform a Chi‐square Test of Independence on data from a testcross. Which of the following calculated chi‐squares would agree with the conclusion that locus E and locus M are linked? You may consult the chi‐square distribution table on the last page of this exam.

6.049

Interference refers to the situation when ___________

one crossover inhibits the occurrence of a second crossover.

The transfer of bacterial DNA from one bacterium to another through a bacteriophage is _______

transduction

Which of the following statements about DNA packaging is FALSE?

Bacterial DNA is naked in the cytoplasm and not packaged by proteins.

Two linked genes, (A) and (B), are separated by 18 cM. A woman with genotype Aa Bb has children with a man who is aa bb. The woman’s mother had the genotype aa BB.

What is the probability that their first child will be aa Bb?

41%

A bacterium of genotype a+ b+ c+ d+ is the donor in a cotransformation mapping experiment. The recipient bacterium is a‐ b‐ c‐ d‐. Data from the transduced cells are shown below. Which two genes are closest together on the chromosome?

a and b

Two chromosomes have the following segments, where • represents the centromere:

A B C • D E F G H

K L M • N O P Q R

What type of chromosome mutation would result in the following chromosomes:

A B C • D E F G H

K L M • N R Q P O

Paracentric inversion

The concept that genetic information passes from DNA to RNA to protein is called the

Central Dogma of Molecular Genetics

Which of the following was part of the evidence that DNA is double‐stranded?

The amount of Adenine equals the amount of Thymine, and the amount of

guanine equals the amount of cytosine.

During the _____ cycle, bacteriophages take over the host bacteria, use it to make more phages, and then kill the host cell.

lytic

______ refers to when chromosomes do not separate properly during cell division

Nondisjunction