Mitosis Study Guide

Review

What is the purpose of Mitosis?

Division of cells to grow, or replace old, diseased, dead or damaged body cells

Explain each phase of the cell cycle and draw a

picture of what a cell in this phase might look like

InterphaseCell GrowsDNA is copiedVisible nucleus and nucleolusDNA is uncondensed=chromatin Chromosomes are NOT visible

Interphase

ProphaseVisible condensed double-

stranded chromosomes/ sister chromatids

Centrioles begin to send out spindle fibers

Nuclear envelope disappears

ProphasePlant Cell

Animal Cell

MetaphaseDouble-stranded chromosomes/

Sister chromatids line up in the center of the cell

Spindle fibers connect to the centromeres of each chromosome

Chromatids are being pulled

Metaphase

Plant Cell Animal Cell

AnaphaseSister chromatids are moving

apart= chromatids once splitChromatids are moving towards

the poles of the cellSpindle fibers pull the chromatids

to the poles

Anaphase

Plant Cell Animal Cell

TelophaseNew nuclear membrane begins to

form around each set of chromatids

Cytoplasm begins to divideChromatids uncoil= chromatin

once uncondensedVisible cleavage furrowSpindle fibers disappear

Telophase

Plant Cell Animal Cell

CytokinesisCytoplasm divides2 new daughter cells identical to

the parent cellAfter cytokinesis, cell return to

interphase

CytokinesisPlant Cell Animal Cell

Explain what happens to the cell’s genetic information during the following

parts of the cell cycle

InterphaseDNA is copiedDNA is uncondensed=chromatin Chromosomes are NOT visible

ProphaseVisible condensed double-

stranded chromosomes/ sister chromatids

MetaphaseDouble-stranded chromosomes/

Sister chromatids line up in the center of the cell

Chromatids are being pulled

AnaphaseSister chromatids are moving

apart= chromatids once splitChromatids are moving towards

the poles of the cell by means of the spindle fibers

TelophaseNew nuclear membrane begins to

form around each set of chromatids

Chromatids uncoil= chromatin once uncondensed

Cytokinesis2 new daughter cellsWith identical DNA within each

How do daughter cells produced in mitosis compare to the original cell?

The daughter cells are identical to the original (parent) cell.

Same function, same internal parts, SAME DNA

Explain the relationship that mitosis has with cancer.

Cancer is unregulated cell growth and division.

How do Chemotherapy drugs used in cancer treatment affect Mitosis?They stop cell division at various

stages of the cell cycle◦Prevent DNA replication

(doxorubicin)◦Cross-link with DNA to prevent

synthesis (cyclophospliamide)◦Blocks cells from making nucleotides

(methotrexate)

Why does chemotherapy tend to cause side effects like hair loss

and gastrointestinal issues?They kill off the rapidly dividing

cells of the body kill not only rapidly dividing

cancer cells but also cells of the rapidly dividing cells like those that make up hair, bone marrow, and the GI tract

Effects are NOT usually permanent

What is the difference between a scanning electron microscope and a transmission electron microscope?

Scanning Electron Microscope◦The entire organism/specimen can

be used, but it must be coated in a thin layer of gold atoms

◦The imaged obtained is a 3 dimensional surface image

What is the difference between a scanning electron microscope and a transmission electron microscope?

Transmission Electron Microscope◦Uses a thin slice of an

organism/specimen◦Used to study the internal make-up

of the specimen

Scanning Electron Microscope Images

Cat Flea Head

Scanning Electron Microscope Images

Hypodermic Needle

Scanning Electron Microscope Images

Staple Through

Paper

Transmission Electron Microscope Images

Cross Section of a

Sunflower Plant Cell

Transmission Electron Microscope Images

Giardia Cysts

Transmission Electron Microscope Images

Cross Section

of Chloropla

st in a Leaf

How are the pictures they take different?

Scanning Electron Microscope Images show…◦3 dimensional images of surface

Transmission Electron Microscope Images show…◦Internal make-up of the specimen

(cross section)

What types of problems can occur at each stage of the Mitosis?

Prophase: nuclear membrane may not dissolve causing the cell to not be able to go through other stages

Metaphase: Chromosomes may not line up, causing an error in the remaining phases

Anaphase: Sister chromatids may not split correctly, causing an error in the number of chromosomes at each cell pole

Telophase: Chromatids may not unravel, causing the chromatin not to be enclosed in the new nuclear membrane.

What might happen to an organism if their cells lost the ability to divide via Mitosis?

Once that cell dies then that particular cell would not be able to pass on their DNA.

Furthermore, that particular organism would not be able to make new cells after the original parent cell has died

Eventually casing the death of that particular organism