Download Mitosis Study Guide Answers

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
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

Cytokinesis
Plant 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
Chloroplast
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