Ch. 8 DNA Replication, Mitosis, and the Cell Cycle LearnSmart

During development, the process that "carves" out the fingers from a webbed sheet of tissue is called _____

Apoptosis

_____ is a regulated cell death that is a necessary part of development

Apoptosis

Place each description into the correct type of cell death (apoptosis or necrosis): Results from a trauma, such as a cut or bruise Normal part of development Coordinated series if events Disorderly Accidental cell death Programmed cell death

Apoptosis: normal part of development, coordinated series of events, and programmed cell death Necrosis: results from a trauma, such as a cut or bruise, disorderly, and accidental cell death

Which of the following is true with respect to proto-oncogenes? When they are overactive because of mutation, the cell cycle may be accelerated They encode proteins that stimulate cell division Proto-oncogenes encode proteins that normally block cancer development

When they are overactive because of mutation, the cell cycle may become accelerated and they encode proteins that stimulate cell division

Select the statements that are true with respect to the 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 External proteins celled growth factors can regulate cell division, but there are no known internal regulatory proteins Once the cell cycle begins, it cannot be stopped until the cell divides The cell cycle has checkpoints that regulate the transitioning of one phase of the cell cycle into the next

When the requirements of a checkpoint are not met, then the cell will not progress to the next stage of the cell cycle and the cell cycle has checkpoints that regulate the transitioning of one phase of the cell cycle into the next

The major function of nucleosomes is to _____ the DNA within the chromosome

Compact

Following mitosis, what process splits the organelles, cytoplasm, duplicated nuclei, and macromolecules into two daughter cells?

Cytokinesis

In sexual reproduction, the offspring are genetically _____ each other (with the exception of identical twins)

Different from

Unlike normal body cells, what do cancer cells do indefinitely if given enough space and nutrients?

Divide

What statement best described the overall process of mitosis?

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

Place the following apoptotic events in chronological order, beginning with the first event at the top: An immune system engulfs the cell and destroys the remnants A "death receptor" on the cell's membrane is activated Apoptosis-specific proteins begin to destroy the cell

1. A "death receptor" on the cell's membrane is activated 2. Apoptosis-specific proteins begin to destroy the cell 3. An immune system cell engulfs the cell and destroys the remnants

Place these mitotic events in the order that they occur, beginning with the earliest event at the top: Nucleus envelope re-firms Nuclear envelope breaks up and spindle fibers attach to chromosomes Chromosomes align along the equator of the cell Chromosomes condense and become visible Sister chromatids separate

1. Chromosomes condense and become visible 2. Nuclear envelope breaks up and spindle fibers attach to chromosomes 3. Chromosomes align along the equator of the cell 4. Sister chromatids separate 5. Nuclear envelope re-forms

Place the following steps of DNA replication in the order in which they occur, beginning with the first step at the top: Binding of proteins to the two template strands prevents them from rejoining DNA polymerase adds DNA nucleotides to create the newly synthesized strand Enzymes replace the primers, and ligase seal the gaps between existing segments and newly synthesized segments Helicase separated the two template strands of DNA Primase adds short stretched to RNA to the template DNA strand

1. Helicase separates the two template strands of DNA 2. Binding of proteins to the two template strands prevents them from rejoining 3. Primase adds short stretches of RNA to the template DNA strand 4. DNA polymerase adds DNA nucleotides to create the newly synthesized strand 5. Enzymes replace the primers, and ligase seal the gals between existing segments and newly synthesized segments

Place the phases of mitosis in the order that they occur, beginning with the first phase at the top: Telophase Anaphase Metaphase Prophase Prometaphase

1. Prophase 2. Prometaphase 3. Metaphase 4. Anaphase 5. Telophase

Match each organism with the correct number of chromosomes contained in that organism's body cells: Dog, mosquito, rice, human, carp 6 chromosomes 24 chromosomes 46 chromosomes 78 chromosomes 104 chromosomes

6 chromosomes: mosquito 24 chromosomes: rice 46 chromosomes: human 78 chromosomes: dog 104 chromosomes: carp

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

A billion

In prokaryotes, DNA is contained in _____, and in eukaryotes, DNA is contained in _____

A single chromosome; multiple chromosomes

The _____ _____ helps divide the cytoplasm of an animal cell in a process called _____

Cleavage furrow; cytokinesis

Select the types of organisms that can exhibit asexual reproduction: Humans Bacteria Protists Archaea Some multicellular eukaryotes

Bacteria, protists, archaea, and some multicellular eukaryotes

Usually, warts and moles are _____ tumors of the skin, meaning they do not invade surrounding tissues or metastasize

Benign

Bacteria and archaea reproduce asexually by a process called _____

Binary fission

A class of diseases characterized by malignant cells is called _____

Cancer

Genetic mutations can cause changes in proteins that control the cell cycle and lead to a disease characterized by uncontrolled cell growth called _____

Cancer

Select the true statements that describe cancer cells compared to normal cells: Cancer cells divide less frequently than normal cells The cell membrane if cancer cells is more rigid Cancer cells may have multiple nuclei Cancer cells are less specialized than normal cells

Cancer cells may have multiple nuclei and cancer cells are less specialized than normal cells

Select the rapidly dividing cells that are affected by chemotherapy and radiation therapy: Cancer cells Cells of the lymph nodes Hair follicles Bone marrow cells Cells of the digestive tract Brain cells

Cancer cells, hair follicles, bone marrow cells, and cells of the digestive tract

The _____ describes the time from one cell division until the next

Cell cycle

Unlike normal cells, cancer cells do not undergo _____, even when they are damaged

Cell death

During cytokinesis in plants, the appearance of the _____ is the first sign of new cell wall comstruction

Cell plate

Structures that consist of proteins surrounding a pair of centrioles are called _____, which function to organize the proteins that move chromosomes during mitosis

Centrosomes

The cell cycle has internal _____ that do not let the cell proceed to the next stage of the cell cycle until the previous stage is complete

Checkpoints

A replicated chromosome consists of two attached copies called sister _____

Chromatids

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

Chromosomes

What describes the S phase checkpoint?

Ensures that DNA replication occurs properly

In sexual reproduction, the union of sperm and egg occurs in a process called _____

Fertilization

Binary _____ is a type of asexual reproduction seen in bacteria that replicates DNA and distributes other cell parts into two new daughter cells

Fission

Select the phases that occur within interphase of the cell cycle: Cytokinesis G0 Mitosis G2 G1 S

G0, G2, G1, and S

In the _____ phase of the cell cycle, the cell grows, carries out basic functions, and may enter a nondividing G0 phase

G1

The _____ checkpoint takes place before mitosis begins

G2

The last checkpoint prior to the initiation of mitosis is called the _____ checkpoint

G2

Which of the following occurs after the S phase but precedes mitosis?

G2

Sex cells, such as sperm cells or egg cells, are also called _____

Gametes

Match each cancer treatment with how it works: Add functional genes to cells with disabled genes Block the recruitment of blood vessels by a tumor Target specific molecules in cancer cells

Gene therapy: add functional genes to cells with disabled genes Drug therapy: target specific molecules in cancer cells Angiogenesis inhibitors: block the recruitment of blood vessels by a tumor

In order for a cell to divide, by mitosis or meiosis, it needs to first duplicate its entire _____, which consists of all of its genetic material

Genome

Select the processes that are due to mitotic cell division: Growth of a zygote into a multicellular adult Replacement of lost cells Repair after injury Fertilization to form a zygote The formation of genetically different offspring

Growth of a zygote into a multicellular adult, replacement of lost cells, and repair after injury

Match the parts if the chromosomes with their description: Proteins around which DNA winds Stretch of DNA wrapped around proteins; become tightly arrayed during chromatin condensation Place where two sister chromatids attach in a replicated chromosome Replicated copy of a chromosome

Histone: proteins around which DNA winds Centromere: place where two sister chromatids attach in a replicated chromosome Chromatid: replicated copy of a chromosome Nucleosome: stretch of DNA wrapped around proteins; become tightly arrayed during chromatin condensation

In asexual reproduction, the offspring are genetically _____ to each other

Identical

Select the following that are true about growth factors triggering cell division: Growth factors normally act to suppress the cell cycle In response to a signal, a cascade of chemical reactions inside the cell initiates cell division Growth factors "walk" along microtubules to receptors on the nuclear membrane Growth factors bind to receptors on the cell membrane Epidermal growth factor stimulates skin cells to divide

In response to a signal, a cascade of chemical reactions inside the cell initiates cell division, growth factors bind to receptors on the cell membrane, and epidermal growth factor stimulates skin cells to divide

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 occuring

Interphase

Math the following events of the cell cycle with their description: Division of the cell itself Division of the contents of the nucleus The time between cell divisions in which DNA replication, basic cellular activities, and cell growth take place

Interphase: the time between cell divisions in which DNA replication, basic cellular activities, and cell growth take place Mitosis: division of the contents of the nucleus Cytokinesis: division of the cell itself

Proteins called _____ are present at the centromeres of chromosomes and become attached to spindle microtubules during prometaphase

Kinetochores

What is the key feature that classifies a disease as cancer?

Malignant cells

What process gives rise to gametes in humans?

Meiosis

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

Meiosis

Once mitosis has begun, the checkpoint that allows a cell to progress into anaphase is called the _____ checkpoint

Metaphase

A type of cell division called _____ divides a eukaryotic cell's genetic information into two identical daughter cells

Mitosis

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

UV light and chemicals in tobacco are _____, meaning that they damage DNA and cause mutations

Mutagens

The term _____ refers to any change in a cell's DNA sequence

Mutation

Similar to the way evolution acts, _____ in a few cancer cells allows the cells to survive chemotherapy, and these cells go on to divide and produce a "population" of cells that are resistant to chemotherapy

Mutations

Select the true statements about cancer development: Because cancers are genetic, a person can't acquire cancer during their lifetime Mutations that cause cancer can arise in the gametes and not be present in the parents Mutations that cause cancer can appear in adults The mutations that cause cancer can be inherited

Mutations that cause cancer can arise in the gametes and not be present in the parents, mutations that cause cancer can appear in adults, and the mutations that cause cancer can be inherited

Select the true statements about tumor suppressor genes: Normal copies can inhibit apoptosis Normal copies can promote cell division Normal copies can inhibit cell division Normal copies can promote apoptosis They encode proteins that normally block cancer development

Normal copies can inhibit cell division, normal copies can promote apoptosis, and they encode proteins that normally block cancer development

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

Nucleosomes

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

Nucleotides; double helix

Proto-oncogenes that have been mutated are called _____, which can lead to cancer

Oncogenes

Select the types of genes in which genetic mutations can cause cancer to develop: rRNA genes Oncogenes Spliceosome genes Tumor suppressor genes

Oncogenes and tumor suppressor genes

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

Select the products of one cell undergoing mitotic cell division: Organelles distributed to daughter cells Identical genetic material Recombined genetic material 4 daughter cells 2 daughter cells

Organelles distributed to daughter cells, identical genetical material, and 2 daughter cells

During this phase of mitosis, the nuclear envelope breaks down

Prometaphase

Which of the following would you find in chromatin? Proteins for scaffolding Proteins for replication DNA Proteins for transcription Actin molecules

Proteins for scaffolding, proteins for replication, DNA, and proteins for transcription

In a human body, mitotic cell division occurs about 300 million times per minute and acts to _____

Replace cells

Select the processes involved in asexual reproduction: Replication of genetic material Fusion of cells Splitting of one cell into two cells Recombination to produce genetically different offspring

Replication of genetic material and splitting of one cell into two cells

Select all the body and cellular processed that require cell division to function: Reproduction Photosynthesis Growth and development Generate ATP Replace dead cells

Reproduction, growth and development, and replace dead cells

During the _____ phase of interphase, DNA replication occurs

S

The mitotic _____ consists of fibers that will grow outward toward the chromosomes during mitosis

Spindle

Match the stage of cancer with its description: Cancer has spread to lymph nodes and nearby organs but not distant organs Cancer has spread to distant sites and distant organs Cancer has spread to tissue adjacent to the tumor but remains confined to the organ of origin Cancer has spread to nearby tissues beyond the organ of origin but has not yet spread to the lymph nodes

Stage I: cancer has spread to tissue adjacent to the tumor but remains confined to the organ of origin Stage II: cancer has spread to nearby tissues beyond the organ of origin but has not yet spread to the lymph nodes Stage III: cancer has spread to lymph nodes and nearby organs but not distant organs Stage IV: cancer has spread to distant sites and distant organs

Proteins encodes by proto-oncogenes normally act to _____

Stimulate cell division

Normal human cells has a "cellular clock" that limits the number of divisions to about 50, whereas cancer cells have lost this and become "immortal" because their _____ stay too long

Telomeres

In this stage of mitosis, which is called _____, the mitotic spindle disassembles and division of the genetic material is complete, but the cell cytoplasm has nit yet divided

Telophase

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

Select all of following that are true about malignant tumors: They are likely to metastasize They invade adjacent tissue They are surrounded by a tough capsule

They are likely to metastasize and they invade adjacent tissue

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

They fold and wind into a compact form

Select all the true statements with respect to benign tumors: They grow slowly They are likely to spread to invade other parts of the body They are surrounded by a tough capsule to prevent them from spreading They are usually harmless

They grow slowly, they are surrounded by a tough capsule to prevent them from spreading, and they are usually harmless

Select all of the following that are true with respect to the G1 checkpoint: It monitors the spindle and checks that DNA has been replicated completely Through p53, it promotes the expression of DNA damage repair enzymes Through p53, it can promote apoptosis if the DNA damage is too severe It monitors chromosome alignment It screens for DNA damage

Through p53, it promotes the expression of DNA damage repair enzymes, through p53, it can promote apoptosis if the DNA damage is too severe, and it screens for DNA damage

Select all the reasons that cells need to control their rate of division: Too little cell growth will not allow injuries to be repaired All cells in an organism need to divide constantly to replace worn out cells Cells that make up different types of tissues require different rates of division for proper function Uncontrolled cell division can lead to abnormal growth

Too little cell growth will not allow injuries to be repaired, cells that make up different types of tissues require different rates of division for proper function, and uncontrolled cell division can lead to abnormal growth

Select all of the following that can increase the risk of cancer Balanced diet UV radiation Smoking Regular vigorous exercise Sexually transmitted viruses

UV radiation, smoking, and sexually transmitted viruses

Cancer cells are characterized by _____

Uncontrolled cell division

Select all of the following that can lead to the formation of a tumor: Cyclin-dependent checkpoints Uncontrolled cell division Lack of programmed cell death An active p53 protein

Uncontrolled cell division and lack of programmed cell death

Select characteristics of chromosomes in a cell that is preparing to divide: Unwound Visible in the microscope Compact Accessible for replication

Visible in the microscope and compact

Unlike in mice, the drug endostatin _____ in most human patients

Was ineffective