1. Microscopes & Cells

2. Where We’re Going…
There are 2 benchmarks associated with cells at the middle school level.
They are…

3. Benchmarks
SCI.III.1.MS.1- Demonstrate evidence that all parts of living things are made of cells.
SCI.III.1.MS.2- Explain why and how selected specialized cells are needed by plants and animals.

4. Important Concepts From SCI.III.1.MS.1
Types of living things…(each of the 5 kingdoms)
Monerans
Protists
Fungi
Plants
Animals
Parts of organisms…(fungi, plants, animals)
Cells->Tissues->Organs->Organ Systems->Organisms
Common plant/animal cells…
Onion skin cells (plant cells)
Cheek cells (animal cells)
Single Celled Organisms…(Protists)
Paramecium
Amoeba
Euglena
Tools…
Microscope
Magnifying glass/hand lens

5. Important Concepts From SCI.III.1.MS.2
Specialized functions of cells including…
Reproduction
Photosynthesis
Transport
Movement
Disease-fighting
Specialized plant cells including…
Root cells
Leaf cells
Specialized animal cells including…
Red blood cells
White blood cells
Muscle cells
Bone cells
Nerve cells
Egg/sperm cells

6. Cells…
Cells are the smallest units that carry out the activities of life in organisms.
Some are complete organisms , such as unicellular bacteria and protozoa. (Kingdom Monera and Protista)
Others are specialized components of multicellular organisms. (Kingdom Fungi, Animalia, and Plantae)

7. Size of Cells…
Some cells, like bacteria are incredibly small, (.2 micrometer)
Other cells, like the nerve cells that run down a giraffe’s leg can be up to 2 meters long.

8. Cells…
Members of Kingdom Monera are too small to be seen with our classroom microscopes, but we will take a peek at some members of Kingdom Protista in the not too distant future. Both of these Kingdoms contain only unicellular members.
Kingdom Plantae, Kingdom Fungi, and Kingdom Animalia have specialized cells that are part of a larger organism.

9. Cell Types Cells can be either
Prokaryotic-no membrane around nuclear material. “Naked DNA” (bacteria-Kingdom Monera only)
Eukaryotic –have a nucleus with a membrane around it. (all others-Kingdom Protista, Fungi, Plantae & Animalia)
All Eukaryotic cells have similar internal structures.
Like You!...Get it….Eukaryotic…Like “Eu”….

10. Inside Cells…
We will look at cells in the near future, but in order to understand completely, first you should know a few things like…
how to look inside a cell, (microscopes),
how cells work (cell theory)
what to look for inside a cell (organelles).

11. Microscopes A simple microscope has one lens.
By combining 2 lenses, you can get an image that is larger than the image produced with only one lens.
We use compound light microscopes that have two lenses. They let light pass through the specimen and lenses to enlarge the image and bend light toward your eye.

12. Early Microscopes
Early microscopes did not produce clear images, so the discovery of the cell had to wait for microscope technology to improve before that could happen.
Think about it. Glass was not even widely available or used in homes until the 1600’s. It’s difficult to make lenses without glass.

13. Microscopes
Before we can look at microscopic things we need to be familiar with microscopes.
Please see the diagram and function of the parts of the microscope that your teacher has given.
Be prepared for a test on Thursday, June 1st. You MUST PASS THE TEST BEFORE you can USE a microscope.

14. Microscope History
Hans and Zacharias Janssen were father and son lens grinders.
They produced the first compound microscope (2 lenses).

15. Microscope History
In 1665, Robert Hooke looked at cork through a microscope, and observed hollow roomlike structures.
He called them “cells” because they reminded him of the rooms that monks lived in.

16. Microscope History
A few years later, Anton van Leeuwenhoek, a Dutch fabric merchant and amateur scientist, looked at blood, rainwater & scrapings from teeth.
He noted that some seemed to move, and realized that he was looking at living things.

17. Microscope History
Eventually the observations and discoveries of many scientists led to Cell Theory.
Today we continue to learn new things and build upon this body of knowledge.

18. Cell Theory Cell theory states that…
1. All organisms are made up of one or more cells.
2. Cells are the basic units of structure and function in all organisms.
3. All cells have evolved from other cells.

19. What’s Inside a Cell?
Organelles are very similar to human organs in that they help perform specific functions. The organelles just have stranger names.
So that you’re not too confused as we continue, here’s a glimpse at the big picture.
Link to organelle diagram.
Another Link to organelle diagram.
Interactive Cell Diagram
Several handouts of cells. Pass out. Use overhead transparencies as well.

20. Cell Organelle Overview Video Clips…
Types of Cells
The Living Cell: Structure and Function
Introduction to the Cell

21. Inside Cells…
You will need to know the functions of the following cellular organelles…
vacuole
Nucleus
Cell membrane
Cell wall
Cytoplasm
Mitochondria
Golgi bodies
Lysosomes
Chloroplasts
Chlorophyll
Endoplasmic Reticulum

22. Organelles…
A cell membrane is a structure that forms the outer boundary of the animal cell and allows only certain materials to move into (food & oxygen) and out of (wastes) cells.
It can be thought of as a “bag” that holds the rest of the stuff inside the cell.
Link to cell membrane photo

23. Organelles…
Cytoplasm is the gel-like material inside the cell. (Like jello or a raw egg white)
It is a mixture of proteins, fats, carbohydrates (sugars), salts, water and other substances.
The structures within the cytoplasm of cells are organelles .
cytoplasm moves around within the cell, organelles can come into contact with one another, allowing certain processes to occur. This movement of the cytoplasm is called cyclosis.

24. Organelles… Each organelle has a responsibility or function.
Mitochondria break down food for energy.
They can be thought of as the “powerhouse of the cell.”
Link to mitochondria photo
Link to another mitochondria photo
Link to mitochondria diagram

25. Organelles Vacuoles store food, water, waste materials.
They can be thought of as the “Stomach of the cell”.
Video of vacuole contracting

26. Organelles
Endoplasmic Reticulum is involved in the movement of material.
It can be thought of as the “highway of the cell”.
Link to photo of ER
Link to diagram of ER

27. Organelles
The rough endoplasmic reticulum contains on it smaller organelles called ribosomes.
Ribosomes make proteins.
They are part of the “manufacturing centers” of the cell.
Look back at the ER images to see if you can see the ribosomes.

28. Organelles Golgi Bodies are also associated with the ER.
Golgi bodies act as a transport, packaging materials into vesicles and sending them off either to other organelles or for removal.
They can be thought of as the “post office” of the cell.
Link to photo & diagram of golgi bodies

29. Organelles
Lysosomes contain powerful digestive enzymes that are used to destroy invading matter and unwanted cellular material.
They can be thought of as the “garbage trucks” or “recycling centers” of the cell.
Link to lysosome picture.

30. Organelles Nucleus is the largest organelle in the eukaryotic cell.
It directs all of the activities of the cell, and can therefore be thought of as the “brain of the cell.”
It also contains the chromosomes, which carry the code for the inherited characteristics of the cell.
Link to nucleus/chromosome photo

31. Organelles
Cell walls are only part of plant cells. They function in providing structure; a skeleton of sorts for the plant.
Link to cell wall picture.

32. Organelles
Plant cells are also unique in that they contain chloroplasts which convert light energy into food.
Chloroplasts are generally green because they contain the green pigment chlorophyll.
Link to chloroplasts/chlorophyll picture.

33. Animal Cells – Human Cheek Cell
We will be looking at some animal cells. You’re an animal and you have cells all over. We will take a look at cells from the inside of your cheek.
Look at some photos of human cheek cells here…

34. Plant Cells- Onion Cell
We will be looking through the microscope at some plant cells. Onion cells are a typical plant root cell.
Click here to see some photos.

35. Plant Cell- Elodea Leaf Cell
The elodea leaves that we will look at represent typical plant leaf cells.
Look at some photos of them here…

36. Kingdom Protista- Unicellular Organisms
We will look at a few Protists.
Protists are classified according to how they move. They use the following…
Pseudopodia
Flagellum
Cilia
You will see examples on the next few pages.
Make jello cell models.
Create and take test.

37. Amoeba Amoeba are one member of Kingdom Protista.
Protists are classified according to how they move.
Amoeba move by using pseudopodia or streaming cytoplasm.
They are predators and hunt for and devour microscopic prey.
This is what an amoeba looks like.
Label me (ditto)
Label me (answers)

38. Euglena Euglena is another member of Kingdom Protista.
Euglena move by rotating a long whip-like appendage called a flagella.
Video
Photo
Diagram

39. Paramecium Paramecium are another type of Protist.
Paramecium move by waving their short cilia like little oars.
Video
Photo
Diagram

40. Cells -> Tissues ->Organs -> Systems ->Organisms
According to one of the benchmarks that were presented at the beginning of this section, we will o look at some specialized eukaryotic cells.
Specifically…
Red blood cells
White blood cells
Muscle cells
Bone cells
Nerve cells
Egg/sperm cells

41. Red Blood Cells
The function of red blood cells is to nourish other cells by carrying food and oxygen to them, and to cleanse other cells by carrying away wastes.
They are part of your circulatory system as well as your immune system.
Red blood cells look like this…
Photograph
Diagram

42. White Blood Cells / Leukocytes
The function of white blood cells (Leukocytes) is to protect the other cells by battling anything that threatens them.
They are part of your circulatory system, and part of your immune system.
Here are what white blood cells look like.
Photograph
Diagram

43. Muscle Cells
The function of muscle cells is to expand and contract. This may either move the body (with the help of the skeleton), or transport fluids (blood) throughout the rest of the body.
They are part of your musculoskeletal system.
Check out what muscle cells look like.
Muscle cell photo/diagram site
Video

44. Bone Cells
The function of bone cells is to provide structure for bones. Bones then provide structure for the rest of the body.
They are part of the musculoskeletal system.
This is what bone cells look like.
Photo
diagram

45. Nerve Cells
The function of nerve cells is to provide a route for electrical stimulation throughout the body.
They are part of your nervous system.
This is what nerve cells look like
Photo
Diagram
Label Me (Ditto)
Label Me Answers

46. Egg Cells
The function of egg cells is reproduction. This promotes survival of the species.
They are part of the reproductive system.
They look like this…
Egg
Photo
Diagram
Label Me (ditto) / Label Me (answers)

47. Are We Done??? I think that covers everything.
Be ready for an Organelle Quiz on Friday, June 9th…..be sure to add it to your agenda.
Let’s go back to the beginning of this power point and review.