Lab 1

Question 1

Ocular

Answer 1

Function: To magnify the specimen. Magnification is usually 10X and is engraved on the top of the objectives.

Question 2

Revolving nosepiece

Answer 2

Function: To house the objectives and allow the various objectives to be moved into or away from the viewing position

Question 3

Iris diaphragm ring (or lever)

Answer 3

Function: Controls the amount of light from the light source

Question 4

Stage travel knobs

Answer 4

Function: To move the slide over the stage surface

Question 5

Magnification

Answer 5

The total magnification of the microscope equals the magnification of the ocular lens times the magnification of the objective lens being used.

Question 6

Cells

Answer 6

are the fundamental unit of life. All living things are composed of cells. While there are several characteristics that are common to all cells, such as the presence of a cell membrane, cytoplasm, DNA and ribosomes, not all cells are the same.

Question 7

two types of cells

Answer 7

prokaryotic and eukaryotic cells

Question 8

Prokaryotic cells

Answer 8

lack a nucleus and Organisms belonging to the domains Bacteria and Archaea are composed of

Question 9

Eukaryotic

Answer 9

cells have a nucleus and organisms belonging to the domain Eukarya (protists, fungi, plants and animals) are composed of eukaryotic cells.

Question 10

Size of cells

Answer 10

Prokaryotic cells are generally much smaller than eukaryotic cells (~about ten times smaller) and lack a nucleus and other membrane-bound organelles, whereas eukaryotic cells are compartmentalized by membrane-bound organelles with specialized functions, and the DNA is contained inside the nucleus.

Question 11

cytoplasm

Answer 11

is the region of the cell outside the nucleus. It contains fluid, ribosomes, the cytoskeleton, and, in eukaryotes, other membrane-bound organelles such as the mitochondria and the chloroplasts (and many others).

Question 12

plasma membrane

Answer 12

is a thin sheet of material that forms the outer surface of every cell. The plasma membrane surrounds all the parts of the cell and serves as the boundary between the cell and its environment.

Question 13

Plant cells

Answer 13

have cell walls

Question 14

Animal cells

Answer 14

do not have cell walls

Question 15

Observing plant cells under the microscope

Answer 15

1. Obtain a clean microscope slide and a cover slip.
2. Take a piece of the Elodea leaf. You may have to cut it in half it is too big.
3. Place the Elodea leaf in the center of the slide.
4. Place a drop of water on the leaf specimen.
5. Touch one side of the cover slip on the drop of water then lower the entire coverslip on top of the specimen.
6. Wipe off any excess water.
7. Examine the wet mount preparation using the scanner, low and high power objectives.
8. Make sketches of your observations. Indicate the magnification of your specimen.

Question 16

Observing animal cells under the microscope

Answer 16

1. Obtain a clean microscope slide and cover slip.
2. With a clean toothpick, gently scrape off a thin layer of cells in the inner lining of your cheek.
3. Spread the cheek cells specimen in the center of the clean microscope slide
4. Place a small drop of methylene blue dye over the specimen
5. Place the cover slip on the stained preparation.
6. Wipe off excess fluid.
7. Examine the wet mount preparation of your epithelial cells using the scanner, low, and high power objectives.
8. Make sketches of your observations and indicate the magnification.
9. Label all the cellular parts that you can identify.
   * * DISPOSE OF THE SLIDE, TOOTHPICK, CELLS, COVERSLIP, ETC. IN THE BIOHAZARD CONTAINER**

Question 17

Quantitative data

Answer 17

consists of measurements that are done with numbers. Such data is often organized into charts and graphs so that it may be more easily understood.

Question 18

Qualitative data

Answer 18

consists of recorded descriptions which may not be easily given meaningful numbers. For example; the recording of how some chemical smell.

Question 19

DNA is made up of

Answer 19

Adenine (A), Thymine (T), Cytosine (C) and Guanine (G) DOUBLE HELIX

Question 20

RNA is made up of

Answer 20

Adenine (A), Thymine (T), Cytosine (C) and Guanine (G) NO THYMINE- USES Uracil (U). Single Helix