1. Cell Organelles
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

5. 70s 80s Differences between Prokaryotic & Eukaryotic cells
Bacterial cells also contain flagellum, plasmid and capsule.
Feature
Prokaryote
Eukaryote
Size
Small about 0.5 micrometers
Up to 40 micrometers
Genetic material
Circular DNA (in cytoplasm)
DNA in form of linear chromosomes ( in nucleus)
Organelles
Few present, none membrane bound
Many organelles:
Double membranes e.g.: nucleus, mitochondria & chloroplasts
Single membrane e.g.: GA, ER & lysosomes
Cell walls
Rigid formed from glycoproteins (mainly murein)
Fungi: rigid, formed from polysaccharide, chitin.
Plant: rigid, formed from polysaccharides. E.g.: cellulose.
Animals no cell wall
Ribosome’s
70s
80s

6. Cell Organelles 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
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. An illustration of the Fluid mosaic model
The fluid mosaic model describes the structure of the plasma membrane.Different kinds of cell membrane models have been proposed, and one of the most useful is the Fluid-mosaic model. In this model the membrane is seen as a bilayer of phospholipids in which protein molecules are embedded.
An illustration of the Fluid mosaic model

9.                       
                      
Channels/pores- A channel in the cell's plasma membrane. This channel is made up of certain proteins whose function is to control the movement of food and water into the cell. These channels are made up of certain proteins.

10. 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.

11. Centrosome
The centrosome, also called the "microtubule organizing center", is an area in the cell where microtubles are produced.
Within an animal cell centrosome there is a pair of small organelles, the centrioles, each made up of a ring of nine groups of microtubules. There are three fused microtubules in each group.
The two centrioles are arranged such that one is perpendicular to the other.
During animal cell division, the centrosome divides and the centrioles replicate (make new copies). The result is two centrosomes, each with its own pair of centrioles. The two centrosomes move to opposite ends of the nucleus, and from each centrosome, microtubules grow into a "spindle" which is responsible for separating replicated chromosomes into the two daughter cells.

12. 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.

13. 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.

14. 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?

15. 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.

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. Lysosomes function as the cell's recycling compartment.
Lysosomes receive cellular and endocytosed proteins and lipids that need digesting.
The metabolites that result are transported either by vesicles or directly across the membrane.

18.                       Steps in lysosomal formation
The ER and Golgi apparatus make a lysosome
(a) The lysosome fuses with a digestive vacuole (b) Activated acid
hydrolases digest the contents

19. 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
Explain that this diagram shows the mitochondria cut open to reveal the internal membranes.

20. 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. 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.

23.                       
Cell wall & Plasmodesmata
In addition to cell membranes, plants have cell walls. Cell walls  provide protection and support for plants.  
Unlike cell membranes materials cannot get through cell walls. This would be a problem for plant cells if not for special openings called plasmodesmata.
These openings are used to communicate and transport materials between plant cells because the cell membranes are able touch and therefore exchange needed materials.

24. 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?

25. 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?

26. Vesicles This term literally means "small vessel".
                      
This term literally means "small vessel".
This organelle helps store and transport products produced by the cell.
The vesicles are the transport and delivery vehicles like our mail and  Federal Express trucks.
Some vesicles deliver materials to parts of the cell and others transport materials outside the cell in a process called exocytosis

27. Cilia
cilia are thread-like projections of certain cells that beat in a regular fashion to create currents that sweep materials along;                                          

28. Flagella
Flagella may extend to the rear of a cell and push it forward by snakelike wriggling, or stick out in front and draw it along.
We humans possess both flagella and cilia. Each sperm cell is propelled by a trailing flagellum that accelerates the little torpedo forward in its quest to fertilize an egg.

29. 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.