Mitosis study guide answers

Mitosis Study

GuideReview

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

Interphase

Cell Grows

DNA is copied

Visible nucleus and nucleolus

DNA is uncondensed=chromatin

Chromosomes are NOT visible

Interphase

Prophase

Visible condensed double-stranded

chromosomes/ sister chromatids

Centrioles begin to send out spindle

fibers

Nuclear envelope disappears

Prophase

Plant Cell Animal Cell

Metaphase

Double-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

Anaphase

Sister chromatids are moving apart=

chromatids once split

Chromatids are moving towards the

poles of the cell

Spindle fibers pull the chromatids to

the poles

Anaphase

Plant Cell Animal Cell

Telophase

New nuclear membrane begins to

form around each set of chromatids

Cytoplasm begins to divide

Chromatids uncoil= chromatin once

uncondensed

Visible cleavage furrow

Spindle fibers disappear

Telophase

Plant Cell Animal Cell

Cytokinesis

Cytoplasm divides

2 new daughter cells identical to the

parent cell

After 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

Interphase

DNA is copied

DNA is uncondensed=chromatin

Chromosomes are NOT visible

Prophase

Visible condensed double-stranded

chromosomes/ sister chromatids

Metaphase

Double-stranded chromosomes/ Sister

chromatids line up in the center of the

cell

Chromatids are being pulled

Anaphase

Sister chromatids are moving apart=

chromatids once split

Chromatids are moving towards the

poles of the cell by means of the

spindle fibers

Telophase

New nuclear membrane begins to

form around each set of chromatids

Chromatids uncoil= chromatin once

uncondensed

Cytokinesis

2 new daughter cells

With 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

Chloroplas

t 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