smartbook chapter 14

How many hydrogen bonds are formed between adenine and thymine in the double DNA helix?

2

X-ray diffraction images obtained by Rosalind Franklin were used to determine that the diameter of a DNA molecule is Blank______.

2 nm

How many hydrogen bonds form between cytosine and guanine in the DNA double helix?

3

In a G-C pair, guanine forms _____ hydrogen bonds with cytosine.

3

Leading strand synthesis in E. coli occurs via the action of DNA polymerase

3

Which DNA polymerase has a sliding clamp made of two identical protein chains (beta-subunits) that form a circle that is loaded onto the DNA template?

3

Which of these describes the expected experimental results after two rounds of replication, if the dispersive model for DNA replication is correct? Multiple choice question.

3/4 of DNA molecule would be light and 1/4 of DNA molecule would be heavy.

By convention, the sequence of DNA bases is written in the ______ , Correct Unavailable' to ______, direction.

5, 3

Why is the diameter of a DNA double helix 2 nm?

Because each base-pair contains one purine and one pyrimidine

Discontinuous replication occurs on one strand during DNA replication. Which of these are reasons for discontinuous replication?

The 5' to 3' synthesis activity of polymerase The antiparallel nature of the DNA strands

In the Meselson-Stahl experiment, what was the expected composition of DNA molecules after two rounds of replication, if the conservative model was correct?

The DNA strands would be all heavy or all light.

In order to determine the density of DNA strands, Meselson and Stahl used this technique so that DNA fragments would migrate to the area in the gradient where they had the same density.

Ultracentrifugation

The T2 bacteriophage was an ideal model system for the Hershey Chase experiments because ___.

it is made of only protein and dna

Of the following choices, which type of Streptococcus pneumoniae would lead to death if injected into a mouse? Multiple choice question.

live smooth

Meselson and Stahl used two isotopes of ____ in their DNA replication experiments so that the daughter strands could be distinguished from the parental strands.

nitrogen

Short pieces of DNA, created on the lagging strand of DNA during replication, are called __________

okazaki fragments

The polarity of a DNA or RNA strands refers to the orientation of which of the following?

phosphate group to hydroxyl group

Repeating sugar and phosphate units in a single DNA strand make up its _____.

phosphodiester backbone

The enzyme DNA ____ covalently links nucleotides to synthesize new DNA strands together during DNA replication.

polymerase

The enzyme DNA _________ synthesizes the RNA primers required by DNA polymerases during replication.

primase

When trying to discover the substance responsible for transformation, Avery, MacLeod, and McCarty removed 99.98% of the ____ from their preparation and found that the transforming activity persisted.

protein

In the Hershey Chase experiments, the isotope 35S was used to label ___, and the isotope 32P was used to label ___.

proteins, DNA

In each base-pair of a DNA double helix, a two-ringed ____ nitrogenous base is interacting with a single-ringed _____ nitrogenous base, which makes the diameter of the double helix 2 nm.

purine, pyrimidine

a ______ _______ is the partial opening of a DNA helix to form two single strands.

replication fork

The DNA controlled by an origin is called a _______

replicon

The carbon atoms in a sugar ring are numbered in a clockwise direction starting with the carbon atom to the ______ of the oxygen atom.

right

Which enzymes did Avery, MacLeod, and McCarty use in order to identify the genetic material?

rna digesting enzymes, protein digesting enzymes, dna digesting enzymes

Interpretation of the Meselson Stahl data leads to support of this model of DNA replication

semiconservative

Of the following choices, which type of Streptococcus pneumoniae would lead to death if injected into a mouse? Multiple choice question.

streptococcus pneumoniae

Of the following list, which 3 items are required for DNA replication? (options: amino acids, template, ribose, nucleotides, polymerase enzyme)

template, nucleotides, polymerase enzyme

The erroneous hypothesis, which proposed that DNA was a polymer with a four base sequence that never varied, was called the _____ hypothesis

tetranucleotide

In nucleic acids, the prime symbol is used to indicate

the carbon in a sugar rather than the atoms in the bases attached to the sugar

The partial opening of a DNA helix to form two single strands is called _______

the replication fork

The stability of DNA molecules is due to

the sum of many weak hydrogen bonds between base pairs

griffith defined as the transfer of virulence from one cell to another.

transformation

The DNA structure proposed by Watson and Crick involves ____ (options: nitrogenous bases on the outside, two grooves (major and minor), a helical structure, a helical structure, a sugar phosphate backbone)

two grooves (major and minor) a helical structure a sugar phosphate backbone

Franklin determined that the structure of DNA was helical based on

x-ray diffraction analysis

In a DNA double helix, two hydrogen bonds form between ______

adenine and thymine

The term used to describe two DNA strands that run in opposite directions from each other is

antiparallel

The major significance of the Hershey and Chase experiments is that they Blank______.

confirmed that DNA is the genetic material

Which of the following types of Streptococcus pneumoniae bacteria did Griffith inject into mice?

heated, live, smooth, rough

Which of these are involved in the unwinding of DNA?

helicase, topoisomerase, single-strandd binding proteins

Place the steps of lagging strand synthesis in the correct order:

1. synthesize primers using primase 2. synthesize DNA 3. replace RNA primers with DNA 4. seal nicks in the DNA

The basic design of the Meselson-Stahl experiment was to label Blank

DNA and follow it through 2 rounds of replication

The tetranucleotide hypothesis suggested that ________

DNA was a repeat of a four base sequence that never varied

Which of these are part of the Watson-Crick model? (options: the bases of each strand extend to the exterior of the helix, each DNA molecule is composed of two strands that run parallel, each DNA molecule is composed of 2 phosphodiester strands, each DNA molecule is composed of two strands that run antiparallel)

Each DNA molecule is composed of 2 phosphodiester strands. Each DNA molecule is composed of two strands that run antiparallel.

In the Meselson-Stahl experiment, what was the expected composition of DNA molecules after two rounds of replication, if the semiconservative model was correct? Multiple choice question.

Half of the molecules would have 2 light strands, and half would have a heavy and light strand.

The experiments with radioactively labeled phage that showed that DNA was the genetic material were performed by

Hershey and Chase

he DNA fibers Franklin used in her x-ray diffraction studies came from:

Wilkins

While one strand is synthesized continuously, replication is ______ on the other strand, because polymerases can only synthesize DNA in one direction and the two DNA strands run in opposite directions.

discontinuous or lagging

In which of the following chromosomal entities are an individual's traits specified?

genes

The description of transformation as the transfer of virulence from one cell to another was proposed by:

griffith