1. Cell Organelles © J Beauchemin 2006
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
© J Beauchemin 2006

2. Bell ringer
Provide two differences between eukaryotic and prokaryotic cells
Which organism can only be unicellular?
Which macromolecule is responsible for the production of enzymes?
How are RNA and DNA different?

3. Why are most cells small?
Cells are small because their size is limited by their outer surface area.
Smaller they are the more efficient the cells can be
Surface area to volume ratio

4. Surface to Volume Ratio
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
One 4-cm cube
Eight 2-cm cubes
Sixty-four 1-cm cubes
Total surface area (height × width × number of sides × number of cubes)
96 cm2
192 cm2
384 cm2
Total volume (height × width × length × number of cubes)
64 cm3
64 cm3
64 cm3
Surface area: Volume per cube (surface area ÷ volume)
1.5:1
3:1
6:1

5. Hypothesized Origin of Eukaryotic Cells
Biology, 9th ed,Sylvia Mader
Chapter 04
Hypothesized Origin of Eukaryotic Cells
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Original
prokaryotic cell
DNA
1. Cell gains a nucleus by the
plasma membrane invaginating
and surrounding the DNA
with a double membrane.
2. Cell gains an endomembrane
system by proliferation
of membrane.
3. Cell gains mitochondria.
aerobic
bacterium
mitochondrion
4. Cell gains chloroplasts.
chloroplast
photosynthetic
bacterium
Animal cell
has mitochondria,
but not chloroplasts.
Plant cell
has both mitochondria
and chloroplasts.

6. Cell Organelles The club bouncer Organelle= “little organ”
Found only inside eukaryotic cells
All the stuff in between the organelles is cytosol
Everything in a cell except the nucleus is cytoplasm
The club bouncer
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.”

7. Cell Membrane Boundary of the cell Made of a phospholipid bilayer
Emphasize word parts here:
phospho= phosphate head; lipid= fatty acid tail
bi= 2

8. Bell ringer (write the questions)
What part of the cell is made up of phospholipids?
Which part of the phospholipid is hydrophobic?
The tails of the phospholipids are__________

9. 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
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.

10. Cytoskeleton Acts as skeleton and muscle Provides shape and structure
Helps move organelles around the cell
Made of three types of filaments
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.

11. 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
It’s not necessary that the students can read the labels here; just point out the black dots are ribosomes.

12. Bell ringer What is the difference between the smooth and rough ER?
Proteins provide support for different areas of the body, what are the three filaments created by protein?
What is the main function of the nucleus

13. That looks familiar…what is a polypeptide?
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
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.
That looks familiar…what is a polypeptide?

14. Golgi Apparatus Looks like a stack of plates
Stores, modifies and packages proteins
Molecules transported to and from the Golgi by means of vesicles
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.

15. Bell ringer (write the questions)
What is the main function of the Golgi apparatus?
What two places can protein synthesis occur at?
Lipid synthesis occurs in which organelle?
What is the main function of the cytoskeleton?

16. Which organelles do lysosomes work with?
Garbage disposal of the cell
Contain digestive enzymes that break down wastes
Students should recognize the shapes of the Golgi and ER even if they cannot read the captions.
Which organelles do lysosomes work with?

17. 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
Creates energy in form of ATP
Explain that this diagram shows the mitochondria cut open to reveal the internal membranes.

18. Bell ringer: What organelle is known as the powerhouse of the cell?
Refer to question 1: This organelle creates energy in the form of what?
What is the primary function of lysosomes?

19. Energy-Related Organelles: Mitochondria
Biology, 9th ed,Sylvia Mader
Chapter 04
Energy-Related Organelles: Mitochondria
Cell Structure and Function
Smaller than chloroplast
Contain ribosomes and their own DNA
Surrounded by a double membrane
Inner membrane surrounds the matrix and is convoluted (folds) to form cristae.
Matrix – Inner semifluid containing respiratory enzymes
Break down carbohydrates
Involved in cellular respiration
Produce most of ATP utilized by the cell

20. Mitochondrial Structure
Biology, 9th ed,Sylvia Mader
Chapter 04
Mitochondrial Structure
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a.
200 nm
outer
membrane
cristae
matrix
double
membrane
inner
membrane b.
a: Courtesy Dr. Keith Porter

21. Chloroplast Found only in plant cells
Contains the green pigment chlorophyll
Site of food (glucose) production
Bound by a double membrane
Chloroplasts absorb light, which is the catalyst for photosynthesis.

22. Energy-Related Organelles: Chloroplasts
Bound by a double membrane organized into flattened disc-like sacs called thylakoids
Chlorophyll and other pigments capture solar energy
Enzymes synthesize carbohydrates

23. Chloroplast Structure
Biology, 9th ed,Sylvia Mader
Chapter 04
Chloroplast Structure
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a.
500 nm
outer
membrane
thylakoid
space
grana
stroma
thylakoid membrane
double
membrane
inner
membrane b.
a: Courtesy Herbert W. Israel, Cornell University

24. Cell Wall Found in plant and bacterial cells Rigid, protective barrier
Located outside of the cell membrane
Made of cellulose (fiber)
This is an actual microscopic image. Explain that the colors are added digitally to enhance the different parts.

25. What type of microscope may have been used to take this picture?
Vacuoles
Large central vacuole usually in plant cells
Many smaller vacuoles in animal cells
Storage container for water, food, enzymes, wastes, pigments, etc.
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.
What type of microscope may have been used to take this picture?

26. Bell ringer: What things do vacuoles store?
Between plant cells and animal cells, which one has a smaller vacuoles?
Why are chloroplast green?
In what part of the cell are ribosomes created?
The Golgi apparatus is known as the ups of the cell, one reason is due to the transporting of molecules. Molecules are transported by means of _____________

27. Biology, 9th ed,Sylvia Mader
Peroxisomes
Biology, 9th ed,Sylvia Mader
Chapter 04
Cell Structure and Function
Similar to lysosomes
Membrane-bounded vesicles
Enclose enzymes
However
Enzymes synthesized by free ribosomes in cytoplasm (instead of ER)
Active in lipid metabolism
Catalyze reactions that produce hydrogen peroxide H2O2
Toxic
Broken down to water & O2 by catalase

28. Biology, 9th ed,Sylvia Mader
Chapter 04
Peroxisomes
Cell Structure and Function
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
100 nm
© S.E. Frederick & E.H. Newcomb/Biological Photo Service

29. Where else have we talked about microtubules?
Centriole
Aids in cell division
Usually found only in animal cells
Made of microtubules
Microtubules are also part of the cytoskeleton.
Where else have we talked about microtubules?

30. Bell ringer: Which organelle holds the cell together?
Which organelles are not found in animal cells?
Which organelle helps plant cells make food?
Centrioles aid in _____________

31. Quick Review Which organelle is the control center of the cell?
Nucleus
Which organelle holds the cell together?
Cell membrane
Which organelles are not found in animal cells?
Cell wall, central vacuole, chloroplasts
Which organelle helps plant cells make food?
Chloroplasts
What does E.R. stand for?
Endoplasmic reticulum
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.