Classwork: Comparison between Mitosis and Meiosis
Group______Name________________________________________ID__________
Valeria Elizondo A01194577
Martha Moreno A01194588
Introduction to the activity:
The cell is the basic unit of life. It can form unicellular organisms, or join with other cells to form
multicellular organisms. The maintenance and reproduction of these organisms depend on two
processes of cellular division: mitosis and meiosis.
The process of mitosis occurs in somatic or body cells. It is responsible for the production of new
cells that substitute damaged or dead cells, as well as for the production of new cells during growth
and development. For example, every minute, millions of red blood cells must be produced to
replace those that die.
Meiosis is the process of cell division that is present exclusively in cells that will become gametes,
cells responsible for reproduction of the organism. The principle function of meiosis is to produce
gametes that are genetically different from each other and contain half the number of chromosomes
so that during fertilization, that offspring will have the complete number of chromosomes and will be
different from the parents. Therefore, meiosis allows genetic recombination that permits variations
within the same species and assures the evolutionary success of the species.
Materials required
Copy of the activity
Access to internet
Instruction/steps
Part 1: The cell cyle
1. Draw a diagram of the cell cycle indicating each of its stages, as well as the divisions within
each stage. Describe the major activity that occurs in each stage.
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Part II: Comparison of Mitosis and Meiosis
1.
Use your ebook to fill in the following table:
Characteristics of
comparison
Type of cell that it occurs
in
Mitosis
Meiosis I
Somatic
Sexual
Sexual
Total number of cells
produced
1
2
4
Presence of genetic
variation
No
Yes
Yes
Type of cells produced
(haploid or diploid)
diploid cells
Haploid cells
Haploid cells
Importance of the
process
Many Cells are
reproduce
everyday
because of
mitosis.
Cancer
It occurss while
sexually reproducing
organisms.
Impact if the process fails
2.
Meiosis II
Chromosomal
Chromosomal
diseases like down diseases like down
syndrome.
syndrome.
Based on the information in the above table and your eBook, answer the following
questions:
a. What would happen if mitosis did not occur?
The cells could not divvide because mitosis is the process which they divide
b. What would be the consequences if meiosis did not occur?
We wouldn’t be able to live.
c. What would be the effects on evolution of the species if there was no genetic variation?
A population can not evolve in response to changing in enviromental variables, as a result
may face and extreme risk of extinction.
Part III: Define the following terms:
a. Apoptosis: programmed cell death
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b. Cell cycle: an orderly set of stages that occur between the time a cell divides and the
time the resulting daughter cells divide.
c.
Crossing over: occurs between non-sister chromatids of homologous chromosomes
during prophase I of meiosis I.
d. Cytokinesis: It consists of division of the cytoplasm in the following steps
e. Mitosis: Nuclear division in which chromosome number stays constant
f.
Meiosis: Cells are diploid at the beginning of meiosis and haploid at the end.
g. Genetic recombination: the process by wich 2 dna molecules exchange genetic
information
h. Haploid number: is a normal chromosome complement of germ cells (23 in humans)
i.
Diploid number: the number of chromosomes present in the body cells of a diploid
organism
j.
Homologous chromosome: A couple of homologous chromosomes is a set of one
maternal chromosome and one paternal chromosome that pair up with each other
inside a cell during meiosis.
k. Independent assortment: occurs because there are various ways for
chromosomes to line up in metaphase I of meiosis I
l.
Interphase: the resting phase between successive mitotic divisions of a cell, or between
the first and second divisions of meiosis.
m. Nondisjunction: the failure of one or more pairs of homologous chromosomes or sister
chromatids to separate normally during nuclear division, usually resulting in an
abnormal distribution of chromosomes in the daughter nuclei.
n. Oogenesis: the production or development of an ovum.
o. Sister chromatid: Pieces of identical DNA that are crucial in the process of cell
replication and division.
p. Somatic cell: any cell of a living organism other than the reproductive cells.
q. Spermatogenesis: the production or development of mature spermatozoa
r.
Synapsis: the production or development of mature spermatozoa.
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s.
Zygote: a diploid cell resulting from the fusion of two haploid gametes; a fertilized ovum.
t.
Gamete: a mature haploid male or female germ cell that is able to unite with another of
the opposite sex in sexual reproduction to form a zygote.
Evaluation
Evaluation criteria
Contents of the
report
3
2
1
The report contained
a diagram of the cell
cycle, the
comparative table
completed and all
the questions
answered.
All of the questions
were answered
correctly according
to the information
asked for in the
comparison table.
The report contained
a diagram of the cell
cycle, the
comparative table
incomplete and not
all the questions
answered.
None of the
questions were
answered correctly
according to the
information asked for
in the comparison
table.
At least 10 of the
vocabulary terms
were completed
correctly.
Did not follow
teacher´s
instructions with
respect to format
and content.
vocabulary
All 20 of the
vocabulary terms
were completed
correctly.
The report contained
a diagram of the cell
cycle, the
comparative table
was incomplete, and
all the questions
answered.
Some of the
questions were
answered correctly
according to the
information asked for
in the comparison
table.
At least 15 of the
vocabulary terms
were completed
correctly
Report format
Followed teacher´s
instructions with
respect to format
and content.
Followed teacher´s
instructions with
respect to format but
not content.
Analysis of the
information
https://answers.yahoo.com/question/index?qid=20100218112650AAPKlcx
http://evolution.berkeley.edu/evosite/relevance/IIIA2Lowvariation.shtml
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