Bio 101 chapter 8- DNA replication, binary fission, and mitosis

Select all the body and cellular processes that require cell division to function.

replacement of dead cells

reproduction

growth and development

What type of reproduction results in the production of genetically identical offspring?

asexual

Select all the types of organisms that can produce new individuals by asexual reproduction.

many protists

some multicellular eukaryotes

archaea

Bacteria

In sexual reproduction, the sex cells of two different parents fuse to form

a genetically different offspring.

______ is a specialized type of cell division that produces cells that are genetically different from each other.

Meiosis

asexual reproduction

generates offspring that are genetically identical to a single parent

Select the processes involved in asexual reproduction.

splitting of one cell into two cells

replication of the genetic material

Bacteria and archaea reproduce asexually by a process called

binary fission.

Select all of the following that are true about sexual reproduction.

offspring are genetically different from their parents

two parents are required

offspring are genetically different from each other

What process gives rise to gametes in humans?

meiosis

Sperm cells and egg cells are also called

gametes

In asexual reproduction, the offspring are genetically ________ to each other.

identical

mitosis

divides a eukaryotic cell's genetic information into two identical daughter nuclei.

In sexual reproduction, meiosis results in the production of genetically unique sperm cells and egg cells, which are also called

gametes

Select all of the following that are true about apoptosis.

normal part of development

programmed cell death

regulated sequence of eve

In sexual reproduction, the first cell of the next generation (the zygote) is produced by the process of ______, which is the union of the sex cells.

fertilization

Mitosis is cell division that produces

genetically identical nuclei.

A cell's ______is defined as all the cell's genetic material (DNA) and consists of one or more chromosomes containing the DNA.

genome

A eukaryotic chromosome consists of

DNA and associated proteins.

The process of reading a DNA strand and making a complementary DNA copy of that strand is called

DNA replication.

Eukaryotic cells produce new cells in a division process known as ______, which allows for growth and for compensation of cell loss due to wear and tear or injury.

mitosis

A DNA molecule consists of two strands of ______ held together in a ______ structure.

nucleotides; double helix

In order for a eukaryotic or prokaryotic cell to divide, it needs to first duplicate its entire ______, which consists of all of its genetic material.

genome

A cell's genetic material is contained in one or more

chromosomes

DNA replication is called semiconservative because

one strand of a new DNA double helix is newly synthesized and the other strand is from the parent molecule.

What is the role of the enzyme helicase in DNA replication?

unwind the DNA double helix

In a DNA molecule, ______ bonds form between nitrogenous bases, such that A (adenine) pairs with its complement ______, and G (guanine) pairs with its complement ______.

hydrogen; T (thymine); C (cytosine)

What enzyme adds complementary bases to exposed single strands of DNA during DNA replication?

DNA polymerase

What enzyme adds an RNA primer to the template strand of a DNA segment to be replicated?

primase

Why does an RNA primer need to be added to the DNA template for DNA replication?

DNA polymerase can only add nucleotides to an existing strand.

What is the role of the enzyme DNA polymerase in DNA replication?

add complementary DNA nucleotides

Select the steps that must occur before DNA polymerase can synthesize new DNA.

The double-stranded DNA is unwound.

An RNA primer is added.

During DNA replication, a primase enzyme

builds an RNA primer to attract DNA polymerase.

In DNA replication, a(n) _______, which is made of RNA, needs to be added to the DNA template in order for DNA polymerase to add new DNA nucleotides.

primer

Dna polymerase

adds new complimentary dna nucleotides to a single stranded Dna template

Select all of the following that are true about DNA replication.

DNA polymerase can only add new nucleotides to an exposed 3' end.

New DNA is synthesized discontinuously on the lagging strand.

Okazaki fragments are formed on the lagging strand.

DNA replication takes place simultaneously at hundreds of places along the DNA molecule called

origins of replication.

What enzyme has proofreading and repair functions during DNA replication?

DNA polymerase

In DNA replication, gaps between newly synthesized segments of DNA and existing segments of DNA are sealed by enzymes called ______, which form covalent bonds between the two segments.

ligases

On one strand of DNA, called the ______ strand, the 3' end is exposed, and DNA replication can proceed ______.

leading; continuously

Due to its proofreading accuracy, DNA polymerase incorporates an incorrect nucleotide only about one in a ______ nucleotides.

billion

In prokaryotes, DNA is contained in ______, and in eukaryotes, DNA is contained in ______.

a single chromosome; multiple chromosomes

Binary fission is a type of ______ seen in prokaryotes, such as archaea and bacteria.

asexual reproduction

Why does a eukaryotic cell need to package its DNA at times, rather than having it always be accessible to enzymes?

so it can be more easily divided during cell division

Binary fission in prokaryotes begins with the

replication of the single chromosome

Eukaryotic cell division is more complicated than binary fission because eukaryotes house the DNA in

multiple chromosomes.

Eukaryotic chromosomes consist of _______, which is composed of uncondensed DNA and associated proteins.

chromatin

Because DNA polymerase can only add nucleotides to the ______ end of a growing strand, DNA replication on the lagging strand produces shorts pieces called ______.

3'; Okazaki fragments

Human egg and human sperm cells each contain 23 chromosomes, and after fertilization and mitosis, the offspring contains a total of ______ chromosomes in every cell.

46

Units of chromatin called ______ consist of a stretch of DNA wrapped around eight histones.

nucleosomes

Select the needs that must be balanced in a eukaryotic cell with a large amount of genetic material.

packaging DNA so that it can be divided during cell division

allowing DNA to be accessible for cell functions

The two sister chromatids of a replicated chromosomes attach at a point called the

centromere

After eukaryotic DNA replication, what happens to the nucleosomes in chromatin?

They fold and wind into a compact form.

Select all of the following that are components of chromatin.

proteins for transcription

proteins for replication

proteins for scaffolding

DNA

Select all of the following that describe the two chromatids of a single replicated chromosome.

joined to each other at the centromere

identical copies

separated during cell division

A nucleosome is a stretch of DNA wrapped around ______ proteins.

8 histone

When the ______ of a replicated chromosome splits, the two sister chromatids become individual chromosomes.

centromere

In the eukaryotic cell cycle, the time of cell growth between successive cell divisions is called

interphase.

Select all the characteristics of chromosomes in a cell that is about to divide its genetic material in mitosis.

centromere is readily identifiable

compact

What part of the cell cycle occurs immediately after the G2 phase?

mitosis

During a section of the cell cycle collectively called ______, the cell is not dividing, but protein synthesis, cell growth, DNA replication, and basic cell functions are occurring.

interphase

The ______ describes the series of events that occur in a eukaryotic cell from cell division, including division of the genetic material and the cytoplasm, through the interval of cell activity before the next cell division.

cell cycle

Cells in the G1 phase of interphase can enter a functioning but nondividing phase of the cell cycle called

Multiple choice question.

G0

What describes chromosomes at the end of the S phase of interphase?

consist of two chromatids

In the ______ phase of the cell cycle, the cell grows, carries out basic functions, and produces new organelles.

G1

What is the function of centrosomes?

organize the mitotic spindle

The _______ consists of microtubule fibers that move the chromosomes during mitosis.

spindle

Most cells of the human body at any given time are in the ______ phase of the cell cycle.

G0

The initiation of chromosome condensation and the production of proteins that will coordinate the movements of chromosomes during mitosis occur during what phase of the cell cycle?

G2

Which of the following best describes the overall process of mitosis?

The type of cell division that separates chromosomes and produces two daughter cells with identical nuclei.

The mitotic spindle is composed of protein fibers called ______ that coordinate the movements of ______ during mitosis.

microtubules; chromosomes

What statement describes a process that occurs during mitosis?

Duplicated chromosomes line up and are pulled to opposite poles of the cell.

The nuclear envelope breaks down during what phase of mitosis?

prometaphase

Select all the events that occur during prophase.

Mitotic spindle begins to form.

Chromosomes condense.

Centrosomes migrate to opposite poles.

What is the function of proteins called kinetochores that assemble on centromeres?

attach the chromosomes to the spindle

The chromosomes line up along the center of the cell during what phase of mitosis?

metaphase

Select all of the following that occur during prometaphase.

The nuclear envelope breaks down.

Kinetochores assemble on each centromere.

Spindle fibers attach to kinetochores.

The chromosomes condense and become visible under a light microscope and the nucleolus disappears in what phase of mitosis?

prophase

During prometaphase, spindle fibers attach to proteins called ______ that assemble at each centromere of a chromosome.

kinetochores

What occurs during metaphase of mitosis?

Chromosomes align along the equator of the cell.

Select all of the following that occur during anaphase.

centromeres split

microtubules move the poles of the cell farther apart

sister chromatids are pulled toward opposite poles

What describes cytokinesis?

The cytoplasm and two nuclei are distributed into daughter cells.

The sister chromatids are pulled to opposite poles of the cell during what phase of mitosis?

anaphase

Select all of the following that occurs during telophase of mitosis.

A nucleolus forms at each end of the elongated cell.

The nuclear envelope re-forms.

Chromosomes begin to decondense.

In plant cells undergoing cytokinesis, materials for the assembly of a new cell wall are brought to the cell plate by

vesicles of the Golgi.

Select all the examples of cells that divide constantly to produce new cells.

bone marrow stem cells

cells at the tips of plant roots

Select all of the following that are true about growth factors triggering cell division.

A growth factor stimulates the production of new skin cells at a wound site.

Growth factors bind to receptors on the cell membrane.

In response to a signal, a cascade of chemical reactions inside the cell initiates cell division.

What type of cells may divide constantly throughout their life?

stem cells

In animal cells, a cleavage furrow is formed in what stage of the cell cycle?

cytokinesis

Proteins called ______ are chemical signals that bind to receptors on a cell membrane and trigger cell division.

growth factors

Select the statements that are true with respect to cell cycle control.

When the requirements of a checkpoint are not met, then the cell will not progress to the next stage of the cell cycle.

The cell cycle has checkpoints that regulate the transitioning of one phase of the cell cycle into the next.

What checkpoint monitors the cell's supply of DNA nucleotides during DNA replication?

S

During cytokinesis in plants, the appearance of the ______ is the first sign of new cell wall construction.

cell plate

What describes the S phase checkpoint?

ensures that DNA replication occurs properly

The checkpoint that regulates the cell cycle by screening for DNA damage prior to the start of DNA replication during the S phase is called the ______ checkpoint.

G1

The checkpoint that ensures that all chromosomes are aligned and that the spindle fibers are attached correctly is called the _______ checkpoint.

metaphase

The p53 protein acts at the G1 checkpoint to

promote DNA repair

The last cell cycle checkpoint prior to the initiation of mitosis is called the ______ checkpoint.

G2

Select all of the following that are monitored at the metaphase checkpoint.