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COC
BIOLOGY

Answers to the Lab Manual Questions:

Temperature (p.29):

Note: We did not go over this exercise in lab, but after reviewing it several times, I realized that it is an important topic and is not one where you would need an actual thermometer to answer the questions (the illustration in your lab manual is adequate). Please review the answers and ask me if you have any questions.

1a. 180
1b. 1.8

2a. 32
2b. 0

3a. 212
3b. 100

6. No, 37^oC = 98.6^oF [A rough conversion formula between ^oF and ^oC is: ^oF = (^oC x 2) +30]

7. 65^oC

8. No

Pinhole Microscope (p. 64):

1. As you move the object closer to your eye, it appears to get larger.

2. resolution/focus

1. resolution/focus

2. The pinhole microscope blocks out stray light, allowing you to focus closer to the object (the incoming light is more focused than it was before).

Finding and Focusing (p. 65):

1. ə

2. It is reversed and inverted.

3. back

4. left

Depth of Focus: Crossed Threads (p. 66):

1. yellow - top
    red - middle
    blue - bottom

2. iris diaphragm

3. When you change the magnification, the light intensity also changes.

4. open the iris diaphragm

5. You should only use the coarse focus knob on the lowest magnification and you should always move the stage up as you are looking at it from the side (so that it doesn't crush the slide).  You should then look through the ocular lens and move the stage down until the object comes into focus.  Make any necessary adjustments with the fine focus know while still on low magnification.  Then change the objective lens to higher magnification while observing it from the side (again, to ensure the slide is not crushed or that the lens doesn't get scratched on the slide).  From then on, you should only use the fine focus knob to make adjustments to the focus.  If you lose the object or the focus, you should go back to low power and try again.

6. It is very important not to scratch the lens of the microscope or stain it since it is an expensive piece of equipment and a permanent mark will prevent the user from getting a clear image.  Also, some of the slides contain dyes which will permanently stain the surface of the lens or the microscope, so it is especially important when working with those slides that they not get cracked or handled in a way that stains the microscope.

Onion Cells (p. 71):

The onion (plant) cell has a cell wall whereas the cheek (animal) cell has a cell membrane.
Both cells are eukaryotic so they both have a nucleus.

Elodea Leaves (p. 74):

1. green

2. chloroplast

3. Since you see movement in the cells, you can conclude that they are alive.

4. A vacuole will push the contents of the cell (including the chloroplasts) to the edge of the cell, against the cell wall.  That's why it looks as if it is the cells walls that are pigmented green rather than the chloroplasts.

5. The top layer has thick walls.

6. There are chloroplasts in the Elodea leaf cells whereas the onion cells did not contain chloroplasts.

7. Food (which is produced through photosynthesis in the clhloroplasts) is not carried out in the onion bulb.  Instead, the top (green) part of an onion produces the food and sends it down to the roots (bulb) for storage.

Comparison of Color (p. 75):

1. plastid

2. cytoplasm

Zebrina Leaf Epidermis (p. 76):

1. The stomata control air flow (oxygen flows out and carbon dioxide flows in).

2. The stomata contain chloroplasts.

3. The stomata need energy to open and close and by having chloroplasts in the cell that photosynthesize, the cells have an immediate source of energy to perform this function.  The other skin cells of the leaf don't perform any active functions that require energy so they have no need for chloroplasts.

Diet Analysis:

Eat All You Want of This or That (p.309)

1 orange = 68 calories
1 grapefruit = 104 calories
1 egg = 78 calories

1. 104 x 6 = 104 calories

2. You are likely to eat less if you eat 2 grapefruit before each meal.

3. 9 eggs = 702 calories
    6 oranges = 408 calories
This diet is 490 cal less than the 1,600 cal energy-balance diet. (1,600-1,110)

4. 4,200/490 = 8.6 days

Special Prepared Meals (p. 310)

1. It is expensive.

2. You tend to go back to your previous high-calorie meals because you have not made lifestyle changes in our cooking while on the diet.

Butter and Jam on Toast (p. 310)

1. 1 pat of butter = 36 cal
    1 Tbsp. of jam = 56 cal

2. 75 days (4,200/56)

3. 46 days (4,200/92)

No Milk or Steak (p. 311)

1. 8 oz. milk = 165 cal
    6 oz. steak = 646 cal

2. 811 - 400 = 411 cal

3. 4,200/411 = 10.2 days

4. This can be a permanent weight-reduction strategy.

©2003-2004 Dilek Sanver-Wang, MS
Los Angeles, CA USA.  All Rights Reserved.