Jan 27, 2014 (Per. 8)

• Objective: Practice using the compound light microscope

• Do Now: what is a microscope used for?

• HW:• Complete Midterm review packet, continue to review ALL concepts (take notes, make note cards etc.)

• Objective: Describe the different specimens you saw under the microscope

• Do Now: Looking at a specimen, how would you tell if it is a prokaryote or a eukaryote?

• HW:• Midterm review packet through pg. 6 (take notes, make note cards etc.)

Jan 27, 2014 (Per. 6)

Jan 28, 2014• Objective: timeline the history of the use of microscopes• Do Now: complete Review Questions 2 & 3 from the

microscope lab• HW:

• Complete Midterm review packet, continue to review ALL concepts (take notes, make note cards etc.)

Midterm!• Second review session this Thursday room S11 after

school• Midterm is Tues 2/4 at 10:30am• Period 3- Room A214• Period 4- Room A217• Period 6- Room A212• Period 8- Room D261

• On a blank piece of paper, create a table like the one below using the entire paper (make it neat!!)

• With your group, research each of the tissues/organisms and fill in the table.

Prokaryotic & Eukaryotic Specimen Review

Specimen Description (see suggested points)

Drawing (use color and make it look good!)

Adipose (fat) tissue

Cerebellum

Spirogyra

Chick embryo

Bacillus bacteria

Paramecium

For the description look for:• Is the specimen an organism on its own or is it part

of an organism?• Which Kingdom is it in? (Eubacteria, Archaebacteria,

Protista, Plantae, Animalia, Fungi)• Where does this type of organism live? Or what is

the function of this part of the organism?• How does this organism influence other organisms?

Or How does this part of the organism contribute to the whole functioning organism?

• Does it have a natural color? What is its size? • Anything else interesting?

Prokaryotic & Eukaryotic Specimen Review

A1- Adipose tissue (fat) (Multicelluar/Eukaryotic)• Loose connective tissue• Found in multicellular animals• Made of adipocytes (cells that store

fat for energy)• Cushions and insulates the body• Found beneath the skin and

surrounding internal organs• Fat cells can be white or brown (due

to large amounts of mitochondria)

A2- Cerebellum tissue (Multicellular/Eukaryotic)• Found in the brains of multicellular

animals• Part of the brain that deals with motor

function• Allows the body to sense its

surroundings and respond accordingly• Contains granule cells (purple dots) and

Purkinje cells (pink)

B1-Spirogyra (Multicellular/Eukaryotic)• A filamentous green algae• In the Plantae Kingdom• Has a helical arrangement of

chloroplasts• Found in fresh, nutrient rich water• 10-100 μm in width, centimeters long

C1- Chick Embryo (Multicellular/Eukaryotic)• Early developmental stage of a chick (animalia) before

birth• Contains many cell types beginning to specialize to

become tissues and organs• This sample was from around 3 days old• It takes 21 days to grow and hatch the chick

D1- Bacteria (bacillus) (Unicellular/Prokaryotic)• A genus of rod shaped bacteria• Kingdom Eubacteria• Either rely completely on oxygen or have the ability to use

or not use oxygen• May be free living or parasitic (cause illness)• Example: Bacillus anthracis causes the illness anthrax

(deadly infection causing breathing, digestion, and skin issues)

E1- Paramecium (Unicellular/Eukaryotic)• Animal-like (protozoa) protist• Can live in fresh or salt water• Contain cilia (little hairs to help it swim)• Some types allow single-celled green

algae to live inside of them- endosymbiosis!

CELL THEORY & MICROSCOPES All organisms are made of cells.

Despite the different variety of cells, their structure is remarkably similar.

The History of Cell Theory • Consider the inorganic and organic chemicals that we have studied. • Are they living?

• Could you fill a jar with the same number of inorganic and organic molecules normally found in the human body and expect the contents of the jar to be living?

• From the smallest bacterium to the largest redwood tree, all organisms are composed of cells.

No!

NO, they must be in an organized form, inside cells.

CELLSThe smallest unit of a living thing. Can carry out life processes such as cell respiration, photosynthesis (plants), dehydration synthesis and hydrolysis of compounds, growth, reproduction and much more.

The First Microscopes• The human eye can see items as small as a pencil dot on

a page (100m). • BUT the average cell is only 20m in diameter.

Convert:• mm to μm by

multiplying by 1000

• mm to nm by multiplying by 1,000,000

Convert:• μm to mm by

dividing by 1000• nm to mm by

dividing by 1,000,000

IF CELLS ARE SO SMALL, HOW IS IT THAT WE KNOW SO MUCH ABOUT THEM?

Robert Hooke (1665)• English Scientist• Built a compound microscopes made

of two or three lenses. • He observed a thin section of cork

• (the outer, dead layer of a cork tree that forms the bark)

• Described a “great number of tiny little boxes” which he called cells.

• They were actually the cell walls remaining from dead cells.

• Hook is credited with being the first scientist to view and name cells.

Anton van Leeuwenhoek (1674)• Dutch lens maker • Built a much better lens with

which he was able to observe living cells.

• He observed organisms in rainwater, pond water, blood and the grime he scraped off his teeth!

• He called the small organisms he observed “animalcules” or little animals.

• Leeuvenhoek is credited with observing the first living cells.

Matthias Schleiden

• 1838• German

Botanist• Had the benefit

of much more powerful lenses.

• Concluded that all plants are made of cells.

Theodor Schwann

• 1839• German

Zoologist• Independently

concluded that all animals are made of cells.

Rudloph Virchow

• 1858• German

Scientist• Studied cause of

disease• concluded that

all cells come from existing cells.

• This is also called the theory of Biogenesis.

The ideas of Schleiden, Schwann and Virchow form the basis for the cell theory.

The Cell Theory

• All organisms are made of cells

• Can be:• UNICELLULAR

• One Cell

• MULTICELLULAR• Many Cells

1

• Cells are the basic unit of structure and function in living things.

The Cell Theory

2Digestion!

Circulation!

Movement!Reproduction!

Immunity!

• All new cells arise from preexisting cells

The Cell Theory

3

Ocular Rotating

Nosepiece

ScanningLowHighStage ClipsDiaphragmLamp

Light Source

Eye Piece

Arm

Stage

CoarseFine

Base

Other Types of Microscopes• Different types of microscopes produce different types of

images.

These are all images of yeast cells

LM TEM SEM

Light MicroscopeTransmission Electron Microscope

Scanning Electron Microscope

Electron Microscopes• Use a beam of electrons instead of a beam of light to create an image of a specimen

• Creates images with much higher resolution than with a light microscope

• The image is ultimately captured with a camera/computer rather than by the eye

TEM

Views the internal structure by beaming electrons through thin slices of specimen

SEM

Scans the surface of a specimen

Is this a Scanning EM or Transmission EM?

Virtual Electron Microscope

Field of View (FOV)• The diameter of the circle of light you see when you look

through the microscope.

Field of View (FOV) Activities1. With your partner- Carefully read and complete the field of view packet. Feel free to add notes, highlight, etc. Make sure I check your work.

2. Find another pair of students who are done and log on to a computer. Click the FOV link on my teacher home page. Complete the activity and print your results sheet to the classroom printer.

3. Use the tools on the lab table to find the size of a spirogyra cell. Show all of your work on a blank piece of paper (one per group). Thoroughly explain the process you used and any calculations you did. Make sure I check your work.

4. Staple together your papers from activities 2 & 3 and place them up front.