The document discusses the basic structure and functions of cells. It describes the key components of cells, including the plasma membrane, nucleus, mitochondria, chloroplasts, cell wall, and other organelles. The document also explains the differences between prokaryotic and eukaryotic cells and how scientists first discovered and studied cells using early microscopes.
2. Mr. Hunter
Biology
11/15/2012
• Objective(s)
• SWBAT
• Describe the function of the plasma membrane
• Describe function and location of various organelles
• Answer vocab / review questions
• Bell Ringer: What are the two components of the phospholipids of
the cell membrane?
3. The Discovery of The Cell
• All living things are
made up of one or more
cells.
• A cell is the smallest
unit that can carry on all
the processes of life.
4. Microscopes Reveal Cell Structure
Looking at cells Most cells are too small to see with the
naked eye. Scientists became aware of
cells only after microscopes were
invented in the 1600s.
A. Robert Hooke used a crude microscope
to observe a thin slice of cork in 1665.
He saw many small boxes which
reminded him of the small rooms in
which monks lived, so he called them
cells. He observed plant cells.
B. 10 years later a scientist, Anton van
Leeuwenhoek used a microscope to
view pond water. He observed many
small living creatures. He named them
animalcules (tiny animals). They were
singled-cell organisms.
5. A. In 1838, the German botanist Mattias
The Cell – Theory and Schleiden concluded that cells
Features compose every part of the plant.
B. A year later, the German zoologist
Theodore Schwann claimed that
animals are also made of cells.
C. In 1858, Rudoloph Virchow, a German
physician, determined that cells come
from other cells.
D. The works of these three scientist form
the Cell Theory
1. All living things are made of one or
more cells.
2. Cells are the basic units of structure
and function in organisms.
3. All cells arise from existing cells.
6. The Cellular Basis of Life
• All living things share several
basic characteristics:
• Organized parts
• Obtain energy
• Perform chemical reactions
• Change with time
• Respond to environment
• Reproduce
• Maintain homeostasis
• Share a Common History
7. Cell Diversity
• Cells are very different in
terms of their shapes and
functions.
• A cell’s function can
influence its physical
features
8. Cell Size Surface Area
• Cells differ in shape and size. Surface Area
• Some cells may be seen by the
naked eye, such as a giraffe’s
nerve cell ( 6 & ½ ft long) or a
human egg cell (the size of a
period at the end of sentence
in your text book)
• A cell’s size is limited to its
outer surface area to inner
volume ratio.
• Nutrients, Oxygen and Waste
produced must pass through
the cell at its surface. Volume
Volume
9. Two Basic Types of Cells
• Prokaryotes • Eukaryotes
• Single Cell • Made of one or more cells
• Lack membrane bound • Nucleus and membrane
nucleus – control center bound organelles present
of the cell / contains DNA • Larger than prokaryotic
• Lack membrane bound cells
organelles – specialized • More complex structure
bodies with specific jobs
• DNA is found in nucleoid
region
11. Cellular Organization
• Over time, cells began to
form groups that function
together.
Colonial organism:
• Collection of genetically
identical cells that live
together in a connected
group.
• Few activities are
coordinated.
12. Plasma Membrane
• The plasma membrane (cell
membrane) has several functions.
• Selective access
• Separation of internal and external
environments
• Means of waste removal
• Environmental interactions
• Fluid Mosaic Model – The
membrane behaves more like a
liquid than a solid.
• It is a pattern (mosaic) of lipids and
proteins.
13. Cell Organelles
• Organelle= “little organ”
• Found only inside
eukaryotic cells
• Organelles are
structures that have
specific jobs within cells
• All the stuff in between
the organelles is cytosol
• Everything in a cell
except the nucleus is
cytoplasm
15. Nucleus
• Control center of the
cell
• Contains DNA
• Surrounded by a double
membrane
• Usually the easiest
organelle to see under a
microscope
• Usually one per cell
16. Cytoskeleton
• Acts as skeleton and
muscle
• Provides shape and
structure
• Helps move organelles
around the cell
• Made of three types of
filaments
17. Endoplasmic
Reticulum
• A.k.a. “ER”
• Connected to nuclear
membrane
• Highway of the cell
• Rough ER: studded with
ribosomes; it makes
proteins
• Smooth ER: no
ribosomes; it makes
lipids
18. Ribosome
• Site of protein synthesis
• Found attached to
rough ER or floating free
in cytosol
• Produced in a part of
the nucleus called the
nucleolus
That looks familiar…what is a
polypeptide?
19. Golgi Apparatus
• Looks like a stack of
plates
• Stores, modifies and
packages proteins
• Molecules transported
to and from the Golgi by
means of vesicles
20. Lysosomes
• Garbage disposal of
the cell
• Contain digestive
enzymes that break
down wastes
Which organelles do
lysosomes work with?
21. Mitochondria
• “Powerhouse of the
cell”
• Cellular respiration
occurs here to release
energy for the cell to
use
• Bound by a double
membrane
• Has its own strand of
DNA
22. Chloroplast
• Found only in plant cells
• Contains the green
pigment chlorophyll
• Site of food (glucose)
production
• Bound by a double
membrane
23. Cell Wall
• Found in plant and
bacterial cells
• Rigid, protective barrier
• Located outside of the
cell membrane
• Made of cellulose (fiber)
24. Vacuoles
• Large central vacuole
usually in plant cells
• Many smaller vacuoles
in animal cells
• Storage container for
water, food, enzymes,
wastes, pigments, etc.
What type of microscope may have
been used to take this picture?
25. Centriole
• Aids in cell division
• Usually found only in
animal cells
• Made of microtubules
Where else have we talked
about microtubules?
27. Quick Review
• Which organelle is the control center of the cell?
• Which organelle holds the cell together?
• Which organelles are not found in animal cells?
• Which organelle helps plant cells make food?
• What does E.R. stand for?
Notas do Editor
Use this presentation in conjunction with the Cell Organelle note-taking worksheet. Run through the entire presentation before using it in class so that you know what’s coming next! It helps to print the outline and notes to have with you while presenting so that there are no surprises. –JessB.org
You may or may not wish to distinguish between cytosol and cytoplasm. The correct use of each term is shown here. Most high school textbooks, however, use the word “cytoplasm” to mean “cytosol.”
Emphasize word parts here: phospho= phosphate head; lipid= fatty acid tail bi= 2
Cells with more than one nucleus include muscle cells and liver cells, largely because of the massive volume of cytoplasm and number of organelles that need controlling.
Actin, also found in muscle cells, mainly help maintain cell shape in their cytoskeletal role. Microtubules mostly move organelles around the cell. Intermediate filaments also provide structural support.
It’s not necessary that the students can read the labels here; just point out the black dots are ribosomes.
A polypeptide is a chain of amino acids. In this diagram, you can see the ribosome is making a polypeptide, also known as a protein.
AKA Golgi Complex. It is not necessary that the students read the labels, this diagram gives them a general idea of the Golgi’s shape.
Students should recognize the shapes of the Golgi and ER even if they cannot read the captions.
Explain that this diagram shows the mitochondria cut open to reveal the internal membranes.
Chloroplasts absorb light, which is the catalyst for photosynthesis.
This is an actual microscopic image. Explain that the colors are added digitally to enhance the different parts.
The image is 2D, so it must have been a light microscope or TEM. If the cell is very tiny, then a TEM was used. Otherwise, a strong light microscope could have captured this image.
Microtubules are also part of the cytoskeleton.
You may choose to delete the answers from the PowerPoint or change the animation so that they come in after all 5 questions are asked in case you want to quiz students individually at the end.
