Micro Exam 2

The DNA controlled by an origin is called a

replicon

Of the following list, which 3 items are required for DNA replication

template polymerase nucleotides

If normal fibroblast cells are grown in cell culture and the enzyme telomerase is introduced in them, Multiple choice question.

the cells show an increased lifespan

The enzymes in the replisome are active on Multiple choice question.

the leading and the lagging strands

Which of the following is found in eukaryotic cells, but not in prokaryotic cells? Multiple choice question.

A nucleus

How are the origins of replication adjusted in eukaryotic cells, so that early in the embryonic development of eukaryotic organisms DNA can be replicated faster?

Cells can increase the number of origins used in early development.

Ribosomes are necessary to manufacture which of the following molecules?

Proteins

is the nucleic acid manufactured in the nucleus and enters the cytoplasm via the nuclear pores.

RNA

The two main eukaryotic DNA polymerases that extend DNA are

epsilon delta

This type of primase is a combination of RNA polymerase and DNA polymerase that makes short RNA primers and then extends them with DNA to produce the final primer:

eukaryotic

Which of these is not one of the three phases of DNA replication?

extension

Match the function of each DNA polymerase in E. coli. : I II III

acts on the lagging strand to remove primers and replace them with DNA not involved in replication but used for DNA repair the main replication enzyme

In E. coli, oriC is the site at which replication Multiple choice question.

begins

Telomeres are related to

cellular aging

In cells that contain a nucleus, the DNA is divided into multiple linear chromosomes which are organized into a complex structure called

chromatin

RNA polymerases

do not require primers to begin synthesis.

An ______ cuts DNA internally and an ______ cuts at the ends of DNA.

endonuclease; exonuclease

DNA replication in eukaryotic cells is complicated by the fact that eukaryotic cells have

linear chromosomes

The level of telomerase stays high in ______, despite their age. Multiple choice question.

lymphocytes

The surface of the nucleus is bounded by two phospholipid bilayer membranes, collectively called the

nuclear envelope

The ....... is the region of the nucleus where intensive synthesis of ribosomal RNA takes place.

nucleolus

The repository of the genetic information that enables the synthesis of nearly all proteins in a living eukaryotic cell is which of the following structures?

nucleous

Which origins are more sequence-specific?

oriC

Which DNA polymerase acts on the lagging strand to remove primers and replace them with DNA? Multiple choice question.

polymerase I

Which DNA polymerase removes and replaces RNA primer segments in the synthesis of the lagging stand because it has 5' to 3' exonuclease activity.

polymerase I

In the replisome, the ....... is composed of primase, helicase, and accessory proteins that prime the lagging strand.

primosome

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

A chromosome is primarily composed of...

DNA Proteins

The enzyme that relieves DNA supercoiling ahead of the replication fork is

DNA gyrase

Which enzyme covalently links nucleotides together? Multiple choice question.

DNA polymerase

Which of the following organelles are part of the endomembrane system?

Endoplasmic reticulum Golgi apparatus

In prokaryotes, the two daughter molecules (each a double strand) produced at the end of replication are intertwined, similar to two links in a chain. What is the name of the enzyme that unlinks the two daughter DNA molecules?

Gyrase

Which DNA polymerase does not seem to play a role in replication but is involved in the DNA repair process? Multiple choice question.

II

On this strand, the removal of the last primer leaves a gap that cannot be primed at the ends of the chromosome.

Lagging

The repository of the genetic information that enables the synthesis of nearly all proteins in a living eukaryotic cell is which of the following structures?

Nucleus

During the synthesis of the new DNA molecule, where are the new nucleotides added by DNA polymerase?

The 3' end of the growing strand

In a bacterium, where does termination of replication occur, relative to the origin?

The termination site is opposite to the origin

Which of the following describes the structure of DNA inside of the cell's nucleus?

Tightly wound around proteins and packaged into compact units called chromosomes

Why do eukaryotic cells have multiple origins of replication?

To ensure timely replication of multiple, relatively large chromosomes

The enzyme, .... uses ATP to unwind the DNA template.

helicase

Cancer cells contain...

higher levels of telomerase than normal, non-cancer cells.

The sliding clamp of a DNA polymerase

holds the polymerase to the DNA template

The term ....... refers to the coiling of two DNA strands leading to torsional strain.

supercoiling

The enzyme ....... , contains a small internal piece of RNA, which is used as a template to extend the end of a linear DNA molecule.

telomerase

Short, repeated sequences of DNA are characteristic of Multiple choice question.

telomeres