Unit 4B: Asexual Reproduction and Cell Division Test Study Guide

Unit 4B: Asexual Reproduction and Cell Division
Test Study Guide
Surface Area to Volume Ratio:
 Cells function best when…
o The surface area of the cell membrane is __large______.
o The volume of the cell is ___small_____.
 The best combination of surface area and volume factors is one in which (circle one)
o the surface area is
small / large
o and the volume is
small / large
o the surface area to volume ratio: SA /V is small / large
o Cells that conduct transport most efficiently will be (larger / smaller) cells
Cell Division:
 Label the following structure:
Be familiar with the “C” words involved in cell division:
o Centromeres- area of DNA that joins two identical chromatids
o Centrioles- small cylindrical structures made of microtubules that are found only in animal cells
o Chromatid(s)- one arm of a double armed chromosome
o Chromosomes- compact X shaped structures made of DNA
o Chromatin-loosely packed DNA found in non-dividing cells
Cell Cycle:
 What is binary fission? The prokaryotic cell cycle; a form of asexual reproduction
o What organisms go through this process? Bacteria (Proks.)
o On the box to the right, draw the process of binary fission.
 Interphase is an “in-between” period of _______growth_______ which consists of three phases.
 The M phase is where ___cell division__ actually occurs. This phases consist of
o Mitosis or the _______division____ of the nucleus.
o Cytokinesis or the ____division______ of the cytoplasm.
 What is the G0 phase? When does it happen? A period of rest that some cells go into right after the M
What is it?
What happens during this phase of the cell cycle?
(Bullet the important information!)
(Write a short
Interphase- in
between period of
G1- cells grow
Grow in size
make new proteins
makes organelles
S- DNA is
Chromatin is replicated
By the end the cell will have double the DNA
for cell division
Cell makes proteins and organelles that are needed for division
Now cell can divide!
Metaphase 
M Phase- (Mitotic
phase) parent cell
divides into two
daughter cells
Mitosis- nucleus
Longest phase of mitosis
Chromatin condenses to from double armed chromosome
(which attach at the centromere)
Spindles begin to form- they extend from centrosome
region (where centrioles are located)
Centrioles travel to opposite ends of the cell or the poles
By the end the nucleolus disappears
The nuclear envelop breaks down.
Shortest phase of mitosis
Chromosomes line up in the middle of the cell
Spindle fibers attach to the centromeres of each
chromosome (on both sides of the cell)
Sister chromatids separate into single armed chromosomes
and begin to move apart.
Once each of them is at the opposite pole, anaphase is
The condensed chromosomes relax into chromatin
The spindle fibers break off
Nuclear envelope begins to form around both clusters of
Nucleolus reforms in each daughter nuclei
Mitosis is now complete
Second part of the M phase
Cytoplasm is split into half
Cell splits into two
Usually occurs at the same time
as telophase
A cell plate is
formed which
becomes the cell
A cleavage
furrow is formed
by the pitching of
Draw the phase each cell is in and write a short description of
what is happening at each phase.
Regulating the Cell Cycle:
 What is apoptosis? When does it occur? Programed cell death that occurs when there is a problem with
the cell that cannot be fixed
Cancer is a ____disease___ of the cell cycle because it is ___uncontrolled_ cell division.
A tumor is a ___mass________ of cells.
o Malignant tumors ______invade___ and _destroy_ surrounding tissue.
o Benign tumors do not ___spread__ to surrounding tissue.
What causes cancer? Defects/mutations in genes that regulate the cell cycle.
Only mutations in _sex_ cells (sperm and egg) will be passes from parent to offspring.
Treatments for Cancer: