Download Unit 4: Cells

Unit 4: Cells - Part One
Test Date: December 17th and 18th
Project Due Date: _________________
Essential Concepts and Skills
1. Explain why cells are called the basic units of life.
a. All living things are made of one or more cells.
b. All cells come from pre-existing cells.
c. Cells are very small to make it easy for nutrients to enter the cell and for waste to
exit the cell.
2. Describe specific examples that illustrate the relationship between cell structure
and cell function.
a. The shape of the cell is related to the job of the cell.
b. Red blood cells are smooth and round so the can easily slip through very small
blood vessels (capillaries).
c. Muscle cells are long and elastic so they can contract and move an organism.
d. Paramecia are covered with cilia and shaped like a torpedo so they can swim.
e. Paramecia are microscopic, unicellular organisms that belong to the Kingdom
Protista.
3. Compare and contrast prokaryotic and eukaryotic cells.
a. Prokaryotes are much simpler and usually smaller cells (no nucleus).
b. Eukaryotes have a membrane bound nucleus in their cells.
c. Members of the Kingdom Archaebacteria and Eubacteria are prokaryotes;
members of the protist, fungi, plant and animal kingdoms are eukaryotes.
d. Be able to identify diagrams of prokaryotic and eukaryotic cells.
4. Describe the difference between plant and animal cells.
a. Plant cells have a cell membrane and a cell wall, while animal cells only have a
cell membrane.
b. Plant cells have mitochondria and chloroplasts, while animal cells have only
mitochondria.
c. Plant cells have a single, large vacuole while animal cells have many, small
vacuoles.
d. Animal cells have centrioles that assist in cell division while plants do not.
5. Identify in a diagram and describe the functions of cellular organelles.
a. Nucleus: controls the cell’s activities and contains DNA.
b. Nucleolus: located inside the nucleus, makes the ribosomes for the cell.
c. Nuclear Membrane: bilipid layer that surrounds the nucleus.
d. Ribosomes: make proteins.
e. Mitochondria: turns food into energy (cellular respiration).
f. Endoplasmic reticulum: holds ribosomes and transports proteins within the cell.
Found as rough and smooth.
g. Golgi body: packages and sends proteins out of the cell.
h. Lysosomes: (suicide packs) contain digestive enzymes.
i. Cell membrane: (also called plasma membrane) controls what materials enter and
leave the cell because of diffusion or transport (homeostasis). This membrane is
Readings
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diagram
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j.
k.
l.
m.
n.
o.
flexible.
Cilia/flagella: hair-like structures that help in movement of the organism (cilia
are many small “hair-like” structures around the organism and flagella is one
long “whip-like” structure).
Microtubules and cytoskeleton: internal structures that give the cell support and
structure.
Vacuoles: serves for storage of many substances for the cell. A plant has one and
animals have many.
Centrioles: specialized microtubules that aide in reproduction of animal cells
only.
Cell wall: gives support to plant cells because cellulose is rigid.
Chloroplast: contain the pigment chlorophyll and use the sun’s energy to make
food.
6. Describe the classification of bacteria.
In the beginning all prokaryotes were simply “bacteria” and lumped in the Kingdom
Monera.
a. Eubacteria contain peptidoglycan, a carbohydrate, in their cell walls.
b. Archaebacteria do not have petptidoglycan. In addition their DNA sequences are
more similar to eukaryotes then eubacteria.
7. Describe how to identify and name prokaryotes
a. Bacilli: rod shaped
b. Cocci: spherical shaped
c. Spirilla: spiral shaped
d. Strepto (prefix): form a chain
e. Staphylo (prefix): form a cluster
f. Diplo (prefix): form pairs
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To name prokaryotes each prefix is placed before the shape, describing what the
prokaryote looks like. Ex: Staphylococcus
8. Describe how bacteria reproduce and grow.
a. Binary Fission: asexual reproduction where it replicates DNA, divides in half and
produces two identical daughter cells.
b. Conjugation: the transfer of genetic material from one bacteria to another.
c. Endospore: when conditions are unfavorable, the bacteria can produce a
thickened cell wall that allows it to remain dormant until times are favorable.
Assessments
- Cells Alive Webquest
- Microscopes Letter ‘E’ lab
- Cell Travel Poster Project
- Lots of worksheets!
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