Chapter 10 smartbook

How do bacteria reproduce?

binary fission

Order the steps in binary fission from first to last, starting at the top.

1 - Bacterial DNA molecule replicates 2 - Cell elongates and the DNA is partitioned such that the origins are at the 1/4 and 3/4 positions in the cell 3 - Septation begins 4 - Cell pinches in two, forming two daughter cells

During telophase, chromosomes uncoil to allow for gene

expression

Cytokinesis involves the formation of a cleavage ______ in animal cells and a cell ____ in plant cells

furrow, plate

Two irreversible points in the cell cycle are replication of ______ material and ______ of sister chromatids.

genetic; separation

One complete set of chromosomes necessary to define an organism is also known as the ________ number of chromosomes.

haploid

During the five phases of ________, the replicated genetic material is partitioned into _________ new nuclei.

mitosis, 2

During telophase, the nuclear envelope re-forms to produce two separate

nuclei

The bacterial genome consist of a single loop of DNA located in which of the following regions of the cell?

nucleoid

The region in a bacterial cell where DNA is located is called the

nucleoid

What type of genes were discovered in viruses and can cause a malignant transformation when introduced into a cell?

oncogenes

In bacterial cells, the replication of DNA begins at a specific site called the ______ of replication, and proceeds in both directions around the circular DNA until a specific _________ site is reached.

origin and termination

Cdks are enzymes which regulate proteins within the cell cycle via __.

phosphorylation

Cytokinesis in _______ cells does not involve a cleavage furrow, but rather a cell plate.

plant

In which of the following cells does cytokinesis involve the formation of a cell plate?

plant cells

Which of the following produce a cell plate during cytokinesis?

plant cells

Condensation of chromosomes continues throughout which phase of mitosis?

prophase

Which is the first stage of mitosis?

prophase

Chromosomes are composed of chromatin which is a complex of DNA and which of the following?

protein

The enzymatic activity of MPF involves the phosphorylation of which types of molecules?

proteins

Which of the following does not occur during the mitosis phase of the cell cycle?

replication of chromosomes

After DNA replication each condensed chromosome is made of two identical halves called

sister chromatids

The ________ apparatus is broken down during telophase.

spindle

During the stage of mitosis known as ______, gene expression resumes, as chromosomes uncoil.

telophase

What phase of mitosis is characterized by the reformation of the nuclear envelope and the production of two separate nuclei?

telophase

When is the spindle apparatus broken down?

telophase

Place the events that occur during the action of a growth factor on a target cell in the correct order, starting at the top.

1. Growth factor binds to receptors 2. Growth factor receptor initiates MAP kinase cascade. 3. A protein kinase enters the nucleus and activates specific transcription factors. 4. G1 cyclones are produced.

What is the haploid number of chromosomes in humans?

23

Typically, a dividing mammalian cell completes its cell cycle in about how many hours?

24 hours

Identify the diploid number of chromosomes in humans.

46

Chromatin is a complex with 40% DNA and

60% protein

During anaphase, two forms of movement take place simultaneously and as a result sister chromatids are pulled towards opposite poles of the cell. The two forms of movement are commonly referred to as anaphase ________ and anaphase

A and B

In a typical, mature, dividing mammalian cell, what proportion of the cell cycles is taken by mitosis?

A very small fraction (about 5%)

The cyclosome (APC/C) triggers the beginning of ______ during mitosis.

Anaphase

The cyclosome (APC/C) triggers the beginning of _________ during mitosis.

Anaphase

During anaphase, chromosomes move towards the opposite poles of the cell using two types of movements. What are those movements usually called?

Anaphase A Anaphase B

The ______ enzymes control progression through the checkpoints in the cell cycle.

CDK

Phosphorylation within the cell cycle is performed by enzymes called

CDKs

What enzymes control the progression of cells through the cell cycle checkpoints?

CDKs

Which are the core histones of the nucleosome?

H2A H2B H3 H4

The nucleosome core includes two each of four histones named

H2A, H2B, H3, H4

Which of the following cells never leave the G2 phase of the cell cycle?

Human neurons Human muscle cells

Which statement accurately compares cell division in bacterial and eukaryotic cells?

In both types of cells, cell division produces two new cells with the same genetic information as the original cell.

If cells do not have the appropriate growth factors, they will spend most of their time in this phase of the cell cycle.

G1

In a cell's life, cell growth occurs primarily during what phase?

G1

In yeast cells the Cdc2 enzymes works with different cyclins to control which checkpoints in the cell cycle?

G1, S, G2, M

Condensation of chromosomes is initiated in the _____ phase of interphase and continues until the end of prophase.

G2

In the eukaryotic cell cycle, what is the name of the phase that occurs after the replication of DNA and before the start of mitosis?

G2

Which of the following phases occurs after the replication of DNA and before the start of mitosis?

G2

What are the three checkpoints at which the cell cycle can be delayed, or even halted, depending on the cell's internal state and any external signals it may have received?

G2/M checkpoint G1/S checkpoint Metaphase checkpoint

During _________ , which includes the G1, S and G2 phases of the cell cycle, the cell grows and chromosomes replicate in preparation for cell division.

Interphase

While preparing to divide, the cell grows and copies its chromosomes during which stage?

Interphase

Choose all true statements about the activity of MPF.

MPF acts as a protein kinase MPF activity varies during the cell cycle

MPF is an acronym for

Maturation-promoting factor

Proto-oncogenes are

Normal cellular genes that become oncogenic when mutated

The two main classss of cancer causing genes are ______ and tumor-suppressor genes.

Oncogenes

A _______ is a cluster of cancerous cells that have lost control of their growing.

tumor

________ is a term to describe cells growing out of control.

cancer

What is a sequence of growth, replication, and division that produces new eukaryotic cells called?

cell cycle

What usually occurs during the G1 phase?

cells are growing

If necessary (e.g., if DNA is damaged), the cell cycle can be arrested at specific points called

checkpoints

Cytokinesis in animal cells involves the formation of a _______ furrow around the cell.

cleavage

Cytokinesis in animal cells involves the formation of a __________ furrow around the cell.

cleavage

The key event in anaphase is the removal of _____ proteins from the centromeres of sister chromatids.

cohesin

When DNA replicates, the sister chromatids are held together at their centromeres by which of the following complex of proteins?

cohesins

The cell ______ of multicellular eukaryotes is regulated by multiple Cdks and external signals.

cycle

The cell ________ of multicellular eukaryotes is regulated by multiple CDKs and external signals.

cycle

Full activation of the Cdc2 kinase requires complexing with a _______ and the correct pattern of phosphorylation.

cyclin

Protein kinases that regulate the cell cycle and are only active when complexed with the protein cyclin are called

cyclin-dependent kinases

The ________ is another name for the anaphase-promoting complex (APC/C).

cyclosome

The call cycle of multicellular eukaryotes is regulated by several __________ and many different ________ signals.

Cdks; external

In multicellular eukaryotic organisms, the production of new cells follows a highly regulated sequence of growth, DNA replication, and division. This sequence is referred to as the cell ________, which consists of the G1, S1, G2, and M phases.

Cycle

Select the two components of an active Cdk.

Cyclin A protein kinase

Nucleosomes are composed of ________ and _______ proteins.

DNA and histone

Select all of the characteristics of growth factors.

Each growth factor is recognized by a specific cell surface receptor. Over 300 growth factors have been identified that can be grouped into 30 families.

MPF was first discovered in studies of

Frog oocytes

Bacterial cells divide to produce new cells for which of the following?

Population growth Reproduction

_________ -__________ are normal cellular genes that becomes oncogenic when mutated.

Porto-oncogene

Which of the following is the key event in anaphase?

Removal of cohesin proteins from the centromeres of sister chromatids

During the ______ phase of the cell cycle, the chromosomes are replicated.

S or synthesis

During which phase of the cell cycle are the chromosomes replicated?

S phase

Cells control the cell cycle by integrating internal information and external signals and delaying (or even halting) the cell cycle at ________ (number) checkpoints.

Three

In order to cause cancer, both alleles of a ______-_______ gene mush lose function (usually through mutation).

Tumor-suppressor

The TP53 is a _________-suppressor gene. The encoded p53 protein halts mitosis and can even cause a cell to undergo programmed cell ________, or apoptosis, if DNA is severely damaged.

Tumor; death

At the beginning of which phase do the centromeres of sister chromatids split apart allowing sister chromatids to separate from each other?

anaphase

During the ____ of mitosis, the centromeres of sister chromatids split apart allowing sister chromatids to move away from each other.

anaphase

The shortest stage of mitosis is

anaphase

Which of the following is the shortest stage of mitosis?

anaphase

Histone proteins have a positive charge due to an abundance of which of the following amino acids?

arginine and lysine

By applying whole-genome sequencing techniques to cancer cells, scientists have discovered that

different cells in a tumor can have different spectra of mutations

The cells of many eukaryotic organisms contain two sets of chromosomes and are said to contain a _________ number of chromosomes.

diploid

Cell division in both bacterial and eukaryotic cells produces genetically __________ cells.

identical

During prometaphase, which protein complex on each sister chromatid attaches to the spindle?

kinetochore

During prometaphase, sister chromatids attach to the spindle by their _____, which are attached to the centromere region of each sister chromatid.

kinetochores

During ____ the chromosomes are aligned midway between the spindle poles.

metaphase

The pairs of sister chromatids align themselves in a single row along a plane half way between the poles during which phase of mitosis?

metaphase

The German biologist, Walter Flemming, was the first to microscopically observe the process of

mitosis

The phase of the cycle during which the spindle apparatus assembles, binds to chromosomes, and moves sister chromatids apart, is

mitosis