Chapter 13 + 14 quiz

DNA consists of two antiparallel strands of nucleotides held together by

hydrogen bonds

Why does the DNA double helix have a uniform diameter?

purines pair with pyrimidines

How many Barr bodies does a normal human female contain in each diploid cell?

2

Bonus: If 14% of the nucleotides from a DNA molecule contain the base T, what percent will contain the base G?

36%

New combinations of linked genes are due to which of the following?

Crossing Over

A Barr body is normally found in the nucleus of which kind of human cell?

Somatic cells of a female only

Which is not a component of nucleic acids?

Sulfur

In humans, if an XY individual had a deletion of the SYR gene, that person would

develop as a female

Watson and Crick developed a model of DNA in which the two strands twist into the shape of a ________.

double helix

Certain genetic recessive disorders, like color-blindness, are more common in males. Why?

the gene is located on the X chromosome

________ is the genetic material for all cellular organisms and some viruses.

DNA

During replication, which enzyme opens the DNA double helix?

DNA helicase

Which of the following investigators was/were responsible for the following discovery? In DNA from any species, the amount of adenine equals the amount of thymine, and the amount of guanine equals the amount of cytosine.

Erwin Chargaff

People with Turner syndrome have a genotype characterized as which of the following?

Females with one X chromosome

Mendel. Watson. Griffith. Crick. Morgan.

Morgan

Occasionally, chromosomes fail to separate during meiosis, leading to daughter cells that have an abnormal number of chromosomes. This phenomenon is called

Nondisjunction

The frequency of crossing over between any two linked genes will be which of the following?

Proportional to the distance between them

If we think of the DNA double helix as a twisted ladder, what makes up the rungs or steps of the ladder?

Purines and Pyrimidines

The method of DNA replication, where each original strand is used as a template to build a new strand, is called the

Semiconservative method

One possible result of chromosomal breakage is for a fragment to join a nonhomologous chromosome. What is this alteration called?

Translocation

During DNA replication, DNA Polymerase I removes the RNA primers and then fills in the gap.

True

When a female only has 1 X chromosome X chromosome inactivation.

Turner syndrome

Of the 23 pairs of human chromosomes, 22 pairs are homologous and are found in both males and females. These are called ________.

autosomes

Because the two strands of a DNA molecule are ________ to each other, each one can be used as a template to reconstruct the other.

complementary

The chemical bond connecting one nucleotide with the next along one strand of a DNA molecule is called a

covalent bond

Which of the following separates the DNA strands during replication?

helicase

What kind of chemical bond is found between paired bases of the DNA double helix?

hydrogen

In Morgan's experiments, the allele for eye color in Drosophila was shown to be

located on the X chromosome