Chapter 3A: Cells - Assignments
(Print this document to use as a reference for
completing Chapter 3 Assignments.)
Read the materials for Chapter
3:
Note the objectives and read carefully taking notes.
READ the chapter in your book, carefully taking notes.
After reading the materials, complete the following
assignments for Chapter 3:
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- Go to your textbook companion site:
- Click the Key Terms Flashcards item on the left.
- Go through the cards until you know all the terms.
- If you do not have a book (and thus registration code) for the
course yet, click this new terms link.
- If there are terms that you are not certain how to pronounce,
- click the glossary
- Click the first letter of the term at the top of the glossary
- Scroll down until you see the term.
- Click the term and listen to the pronunciation.
- Practice saying and spelling the term until you are certain you know
it.
- Take the test on terms for this chapter.
- Go to Blackboard, Click Assignments, Click the Chapter 3A folder, Scroll down to the bottom of the
page and click the link for the Terms 3A.
- The test is timed and you will only have 15 minutes to take it.
Once you start the test, you must complete it or the test will be
locked. Make certain you watch the clock on the screen so that you
submit it on time.
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Go to grading rubric for this assignment
- Go to your textbook companion site:
- Click the link for chapter web links
- Look at several of the links you think might be interesting
- Select one for which you want to do a report.
- Write a brief summary of what you learned from reading the report.
You must have at least three specific statements of things you learned
(or found interesting). You must include both the name of the
reading and the URL in your summary.
- Post your summary on the class discussion board as a reply to the
appropriate thread.
- Read at least one of the summaries that your classmates have posted.
Reply to your classmate's summary with a list of at least two things you
found interesting about that summary. You must make an original
reply. Any replies that appear very similar to the replies of
another student will not receive credit. It would probably be best
to reply to a summary that does not have a reply to make certain that
your reply is unique.
If you don't have a book yet, you may use the weblinks shown here:
The following topics correspond to those printed at the end of
this chapter in your textbook. They are linked to the McGraw-Hill
Internet database, which is updated regularly, so you can depend on
reliable resources for your research.
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Go to grading rubric for this assignment
Pages 52 and 53 of you textbook have the summary, review questions, and
discussion questions for the chapter. Read the summary, the review
questions, and discussion questions. Go to the class discussion
board. Click the thread for review/discussion/summary. Read the postings of your classmates. YOU MAY NOT post
the same review question, discussion question or summary point as any of
your classmates. If you do not have your book yet, click these links
to see the necessary review questions,
discussion questions, and
summary statements.
- If you select a review question, you must state the question and then
answer it completely.
- If you choose a discussion question, you must state the question and then
answer it completely.
- If you choose a summary question, you must state the the summary point and
then expand on it. For example if you select summary 7, you would answer
something like:
- Botany, the study of plants, apparently began with Stone Age peoples'
practical uses of plants. Eventually, botany became a science as intellectual
curiosity about plants arose. Botany is considered because the
scientific method which describes the procedures of assuming and testing
hypotheses, is used when studying botany.
Your posting must be accurate and must use good grammar. The
subject of your posting should be:
- review 1 (or 2 or 3 or 4 or 5 or 6) OR
- discussion 1 (or 2 or 3 or 4 or 5) OR
- Summary 1 (or 2 through 12)
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Go to grading rubric for this assignment
Click here to see the work of students who have done
this lab
In addition you can use these sites:
to see the type of things you could see if you did this assignment in a
lab. Also you may find it useful to look up things at
Answer the questions in your lab book for Lab 2: The Cell.
If you don't yet have a book, use these questions and
transfer the answers to your lab book when you get it. The quiz (which is
found in Blackboard: Assignments, Chapter 3A) will consist of the questions asked in your lab book as the quiz for
lab 2 as well as questions based on your reading of the work
of students who have done this lab. One question that I can
think of is match these label terms with the Label items A, B, and C on the
diagram above of chloroplast. Another would be to select components of a
cell that you could possibly see using a microscope. Another could be what
power on the microscope was used with a thin slice of potato to show
this leucoplasts. Another would be to pick the term that identifies a
picture from the lab (Chromoplasts, Chloroplasts, Leucoplasts). Your quiz
will be timed.
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Go to grading rubric for this assignment
There will be a 20 question quiz for each chapter. The quiz is open
book and notes, but it is timed and you will only have 15 minutes to answer the
20 quiz questions. However, you may take the test as many times as you
want. Each time to take the quiz, you will be presented with 20 questions
randomly selected from the chapter test pool. NOTE: For the midsemester exam you will NOT be allowed to use notes or take the exam more than
once, but the questions will come from the test pools for chapters 1, 3,4, 5,
and 6..
To take the chapter quiz,
- Scroll down to the bottom of this page. (Click assignments, intro
assignment to get back here)
- Click the "take quiz" link below the Chapter Quiz
label.
- You only have 15 minutes for the quiz, BUT
- You may take it again and again as often as you want until the due date
for the assignment is past.
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|
Activity | Points awarded |
| Terms Quiz (1-5 depending on your score) |
5 |
Weblinks: Summary is grammatically correct with three specific
statements , name of the reading, the URL in your summary. -1 for each
thing missing
2 additional points for the reply to another student with 2 interesting items. 1
for 1 | 8
2 |
review/discussion/summary
grammatically correct with correct subject, item stated, answer correct and
complete.
-1 point for EACH item missing | 5 |
| Lab work depending on quiz score (1 - 10) |
10 |
| Chapter quiz: |
20 |
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- All living organisms are composed of cells. Cells are modified according
to the functions they perform; some live for a few days, while others live for
many years.
- The discovery of cells is associated with the development of the
microscope. In 1665, Robert Hooke coined the word cells for boxlike compartments
he saw in cork. Leeuwenhoek and Grew reported frequently during the next 50
years on the existence of cells in a variety of tissues.
- In 1809, Lamarck concluded that all living tissue is composed of
cells, and in 1824, Dutrochet reinforced Lamarck's conclusions. In 1833, Brown
discovered that all cells contain a nucleus, and shortly thereafter, Schleiden
saw a nucleolus within a nucleus. Schleiden and Schwann are credited with developing
the cell theory in 1838 to 1839. The theory holds that all living organisms
are composed of cells and that cells form a unifying structural basis of organization.
- In 1858, Virchow contended that every cell comes from a preexisting
cell and that there is no spontaneous generation of cells from dust. In 1862,
Pasteur experimentally confirmed Virchow's contentions and later proved that
fermentation involves activity of yeast cells. In 1897, Buchner found that yeast
cells do not need to be alive for fermentation to occur. This led to the discovery
of enzymes.
- Light microscopes can magnify up to 1,500 times. Thinly sliced materials
can be viewed with compound microscopes. Opaque objects can be viewed with stereomicroscopes;
most magnify up to 30 times.
- Electron microscopes have electromagnetic lenses and a beam of electrons
within a vacuum that achieve magnification. Transmission electron microscopes
magnify up to 200,000 or more times. Scanning electron microscopes, which can
be used with opaque objects, usually magnify up to 10,000 times.
- Scanning tunneling microscopes use a minute probe to scan surfaces
at a width as narrow as that of two atoms.
- Eukaryotic cells are the subject of this chapter. Prokaryotic cells,
which lack some of the features of eukaryotic cells, are discussed in Chapter
17.
- Cells are minute, varying in diameter between 10 and 100 micrometers.
They number into the billions in larger organisms, such as trees. Plant cells
are bounded by walls that surround the living protoplast. The cytoplasm contains
a souplike fluid called the cytosol and all cellular components between the
plasma membrane and nucleus.
- A pectic middle lamella is sandwiched between the primary cell walls
of adjacent cells. The primary wall and also the secondary cell wall, often
added inside the primary wall, are composed of cellulose polymers, with hemicelluloses
and glycoproteins. Secondary cell walls contain lignin that strengthens the
wall.
- Living cells are in contact with one another via fine strands of
cytoplasm called plasmodesmata, which often extend through minute holes in the
walls.
- A flexible plasma membrane, which is sandwich-like and often forms
folds, constitutes the outer boundary of the cytoplasm. It regulates the substances
that enter and leave the cell.
- The nucleus is bounded by a nuclear envelope consisting of two membranes
that are perforated by numerous pores. Within the nucleus are a fluid called nucleoplasm, one or more spherical nucleoli, and thin strands of chromatin,
which condense and become chromosomes when nuclei divide. Each species of organism
has a specific number of chromosomes in each cell.
- The endoplasmic reticulum is a system of flattened sacs and tubes
associated with the storing and transporting of protein and other cell products.
Granular particles called ribosomes, which function in protein synthesis, may
line the outer surfaces of the endoplasmic reticulum. Ribosomes also occur independently
in the cytoplasm.
- Dictyosomes are structures that appear as stacks of sacs and function
as collecting and packaging centers for the cell.
- Plastids are larger green, orange, red, or colorless organelles. Green plastids, known as chloroplasts, contain enzymes that catalyze reactions
of photosynthesis. These reactions take place in the membranes of structures
that resemble stacks of coins, called thylakoids, as well as the surrounding
matrix, called the stroma. Plastids develop from proplastids, which divide frequently,
and also arise from the division of mature plastids.
- Mitochondria are tiny, numerous organelles that are bounded by two
membranes with inner platelike folds called cristae; they are associated with
cellular respiration.
- One or more vacuoles may occupy 90% or more of the volume of a mature
cell. Vacuoles are bounded by a vacuolar membrane (tonoplast) and contain a
watery fluid called cell sap. Cell sap contains dissolved substances and sometimes
water-soluble red or blue anthocyanin pigments.
- The cytoskeleton, which is involved in the architecture of cells
and internal movement, is composed of microtubules and microfilaments. Microfilaments
may be responsible for cytoplasmic streaming.
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- What cellular structures can be observed with the aid of light microscopy
and electron microscopy?
- Why are cells so small, and how is this small size beneficial for
transport of substances within and between cells?
- What is the function of the plant cell wall?
- What is the difference between protoplasm and cytoplasm?
- What is the function of a cell nucleus? How does it perform its
function?
- What are plasmodesmata? What is their importance to living plant
cells?
- Describe the major parts and functions of a chloroplast.
- What are the differences and similarities between plant and animal cells?
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- Would you consider any one type of cell more useful than another?
Why?
- After you have completed your introductory plant science course, do you
believe you would be able to determine the function of each of the cell's
organelles in a laboratory? Explain.
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- prokaryotic
- Eukaryotic
- Organelle
- Cell Wall
- Cytoplasm
- Middle Lamella
- Plasmodesmata
- Plasma Membrane
- Nucleus
- Thylakoids
- Plastids
- Chromosomes
- Nuclear Envelope
- Dictyosomes
- chromatin
- Chloroplast
- Stroma
- Grana
- Chlorophyll
- Chromoplasts
- Leucoplasts
- proplastid
- Pectin
- Vacuolar Membranes
- Vacuole
- Endoplasmic Reticulum
- Microtubule
- Microfilaments
- Cell Sap
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- How thick is an Elodea leaf?
- How should a cover slip be applied to a drop of liquid on a microscope
slide
- When chloroplasts appear to be moving within a living cell, what is
the cause of their movement?
- In most living cells, such as those of Elodea, where is the
cytoplasm located? How extensive are plant cell vacuoles?
- What are cytoplasmic bridges?
- What parts of cells are normally visible with the aid of a compound light
microscope?
- If present in a cell, where are anthocyanin pigments located?
- How are starch grains distinguished from parenchyma cells in
a potato?
- What are striae, and where are they located in a spiderwort stamen
hair cell?
- How does a chromoplast differ from a chloroplast?
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In this lab you will use a microscope and examine different
cells and their structures.
At the end of this lab the successful student will be able to
Look at page 33 of your text for a good example of what you will find here. Also,
http://sln.fi.edu/qa97/biology/biopoint4.html will provide you with an
opportunity to look at answers younger students have found to this part of the
lab but you will probably find the cell images and diagrams at this site more
useful
http://web.jjay.cuny.edu/%7Eacarpi/NSC/13-cells.htm.
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Thin slice of potato showing (leucoplasts)
Taken from
http://www.hhmi.princeton.edu/sw/2001/phughs/Presentation1.ppt
tomato (chromoplasts) 3.12
Taken from:
http://sanangelo.tamu.edu/agronomy/tomato/pig.html
If you go to
http://botit.botany.wisc.edu/courses/Botany_130/Eukaryotic_Cell/Index_to_EC.html
you will find
"The Elodea Leaf Cell:
These cells were vitally stained with Janus
Green - students should recognize chloroplasts,
nuclei, and the large central vacuole
in each cell. Determining the extent of the vacuole requires
through focusing.
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Go to this site:
http://www.uwc.ca/pearson/biology/cyclosis.htm and click on the
Cyclosis in Elodea
link to see an example of cyclosis.
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Pond water contains a rich variety of living organisms. Observe various
types of algae and other types of organisms. Draw two or three species in
your notebook.
Here the student fills her dropper with pond water
and carefully places it on a slide for examination.
After the slide is prepared, she carefully examines the water
,
taking careful notes and making diagrams of what she sees. You can see
what she is seeing and recording by going to one of the many sites on the web
that show slides of pond life.
Here you can see the students with their lab groups working on identifying
and drawing their specimens.
Here you can see what Ron found in his pond:
http://www.silkentent.com/gus1911/RonPond.htm, but Ron tends to focus on
animals. If you go to
http://www.lifesciences.napier.ac.uk/algalweb/snaps.htm, you can see studies
from several bodies of water that includes Chlorophytes, Desmids, Diatoms, and
Dinoflagellates.
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and carefully places it on a slide for examination.
After the slide is prepared, she carefully examines the water
,
taking careful notes and making diagrams of what she sees. You can see
what she is seeing and recording by going to one of the many sites on the web
that show slides of pond life. 