Transcript LAB #1

LABORATORY NOTES
LABORATORY #1
1. Lab Safety
2. The Scientific Method
3. The Metric System
Biology 3 Labs
1.
TAKE COPIES OR BUY THE BIO 3 LAB MANUAL FROM THE BOOK
STORE
2. There will be a quiz every week starting the 3rd week of the
semester. 20 multiple choice questions:
• 10 from the previous lab already done
• 10 from the lab that is going to be done that day.
Therefore, you must read and study the lab that is due
that week.
3. You should follow the “recipe” in your Biology 3 Lab Manual
for all the experiments that we are going to do. Read and
study the labs before coming into the lab. Session. I will
give you only the main principles regarding that lab.
4. You have to hand in the lab report regarding the previous
lab session every week.
5. Regarding Project Genesis, I will explain how to do it next
week.
LAB #1: FIRST PART: THE SCIENTIFIC METHOD
1. OBSERVATION: Does Compound X increase plant growth?
2. HYPOTHESIS: Increasing amounts of compound X correlate
w/ increasing plant growth
3. EXPERIMENT: Design a study to test the hypothesis
PEA
PLANT
COMPOUND X
per Day(grams)
1
0
2
1
3
3
4
5
5
7
6
9
3. CONT. EXPERIMENT:
Pea
plant
Compound X
per day (gr)
Height of
plants (cm)
1
0
4.0
2
1
9.9
3
3
13.2
4
5
15.1
5
7
16.8
6
9
17.0
INDEPENDENT VARIABLE: The condition that varies among the
groups
DEPENDENT VARIABLE: The measurements or outcomes
STANDARIZED VARIABLES: Conditions that remain the same so
influence in outcomes remains constant
EXPERIMENTAL GROUPS: The subjects: the plants
CONTROL GROUP: The plants that did not receive treatment
REPETITION of the experiment is important to have more
accurate results
LAB #1: THE SCIENTIFIC METHOD
4. CONCLUSION: Data will support or will not support
the hypothesis: Increased amounts of compound X cause
pea plants to grow taller.
Pea plant
Compound X per Height of plants
day (gr)
(cm)
1
0
4.0
2
1
9.9
3
3
13.2
4
5
15.1
5
7
16.8
6
9
17.0
5. DATA PRESENTATION : GRAPHS (Line graphs or bar graphs)
Plant Height (cm)
(Dependent variable)
Pea Compou
plant nd X per
day (gr)
Height
of
plants
(cm)
1
0
4.0
2
1
9.9
3
3
13.2
4
5
15.1
5
7
16.8
6
9
17.0
20
18
16
15
14
12
10
8
4
1 2 3 4 5 6 7 8 9 10 11 12 13
Compound X (gr)
(Independent variable)
1. Use a line graph: When independent variable is
continuous (infinite)
2. Use a bar graph: When independent variable is
discontinuous ( finite or discrete)
1. Exercise 1A: Assessing hypotheses:
Indicate if you think each hypothesis listed on your
worksheet is good, and if not, suggest changes that
would make it a good hypothesis.
2. Exercise 1B: Effect on distance on making baskets
into a large beaker out of 10 chances at each distance:
a. Distance 0 (Control):
b. Distance 1m:
c. Distance 2m:
d. Distance 4m:
• State your hypothesis, and identify the independent
and dependent variables.
• Graph data (individually)
• Conclusions and answer questions in the worksheet
3. Exercise 1C: Graphing practice
LAB #1: PART 2
THE METRIC SYSTEM
1. The English System:
Length:
1 mile = 1,760 yards = 5,280 feet = 63,360 inches
Volume:
1 gallon = 4 quarts = 8 pints = 16 cups = 128 ounces =
256 tablespoons
Mass:
1 ton = 2,000 pounds = 32,000 ounces
Temperature :
Fahrenheit - Water freezes at 32 ºF and boils at 212 ºF
The metric system is easier and more practical to use.
2. The Metric System:
• Length: Meter
• Volume: Liter
• Mass: Gram
• Temperature: Degree Celsius
Mega…………106 = 1000000
Kilo………..... 103 = 1000
Basic Unit……100 = 1
deci…………..1/10= 10 -1 = 0.1
centi………….1/100= 10 -2 = 0.01
milli…………..1/1000=10-3 = 0.001
micro(µ-)….1/1000000=10-6=0.000001
nano(n-)…….10-9 = 0.000000001
pico(p-)………10-12 = 0.000000000001
2. The Metric System:
• Length: Meter
• Volume: Liter
• Mass: Gram
• Temperature: Degree Celsius
Mega…………106 = 1000000
Kilo………..... 103 = 1000
Basic Unit……100 = 1
deci…………..1/10= 10 -1 = 0.1
Zeros to
the right
centi………….1/100= 10 -2 = 0.01
Zeros to
the left
milli…………..1/1000=10-3 = 0.001
micro(µ-)….1/1000000=10-6=0.000001
nano(n-)…….10-9 = 0.000000001
pico(p-)………10-12 = 0.000000000001
643 m = _____ km
2.4 kg = _____ mg
LAB #1
THE METRIC SYSTEM
1. Exercise 2A:
a. With a meter, measure its width and length of the
class to the nearest meter
b. Measure in centimeters the dimensions of a piece
of paper of your notebook
c. Measure yourself in centimeters
d. With a plastic ruler measure the diameter of a hole
of your notebook to the nearest millimeter
e. Notes:
Length
Volume
• 1 mile= 1.6 Km
1 quart= 0.94 Lts
• 1 inch= 2.54 cm
Mass
• 1 foot= 30.48 cm
1Lb= 0.45 Kg
LAB #1
1. Exercise 2B: Measuring Mass:
a. Place an empty 50 ml graduated cylinder on the
balance and determine its mass in grams.
b. Next, fill the graduated cylinder with 50 ml of
water and measure the mass of both the cylinder
and the water. From this value subtract the mass of the
cylinder to get the mass of the water.
c. Next, take a large paper clip and place it on the
balance and determine its mass in grams.
LAB #1
THE METRIC SYSTEM
1. Exercise 2C: Measuring volume
a. Graduated cylinders are used to measure
accurately volumes while beakers are used to
hold liquids.
b. Fill one 50ml cylinder w/. Water, and add it to a
1Lt beaker. Observe: 50 ml = 1/20 Lt
c. Measure the fluid in flask A to the nearest 0.1ml.
1. Exercise 2C: Measuring volume
d. Using the roller on the pipette pump, gradually
suck up some water until the meniscus reaches
the 0 ml mark. Measure 10 ml of the water into
the sink by rolling the roller in the opposite
direction.
e. Next, measure the amount of fluid in the test tube
labeled B to the nearest 0.1 ml using the 10 ml
pipette.
LAB #1
1. Exercise 2D: Measuring volumes less than 1ml :
Using a micropipettor that measures on a 1µl level.
2. Exercise 2D: Practice measuring volumes using the
micropipettes P20 and P200
3. Read in the lab manual how to do this exercise.
When you are ready to do it CALL ME: I HAVE TO CHECK
AND MAKE SURE YOU HAVE LEARNED HOW TO USE A
MICROPIPETTOR!
4. Using the P200, transfer 100 µl of the blue liquid to
the tube labeled “100” by following the instructions
in the lab manual
5. Using the P20, transfer 10µl of blue liquid to the tube
labeled “10”.
6. Using the P20, transfer 1µl of blue liquid to the tube
labeled “1”.
P20: 0.5 to 20.0 µl
P200: 20 to 200 µl
P1000: 200 to 1000 µl
LAB #1
THE METRIC SYSTEM
1. Exercise 2D: Measuring Temperature:
Use a thermometer to measure the following in
degrees Celsius:
a. the ambient temperature of the lab
b. a bucket of ice water
c. a beaker of boiling water
2. Convert the temperatures on your worksheet from
oC to oF :
oC = 5/9 x (oF - 32)
Convert from oF to oC with the following formulas:
oF = (9/5 x oC) + 32
LAB #1
THE METRIC SYSTEM
1. Exercise 2E :
a. Converting decimal notation to exponential
notation
0.00105 = 1.05 x 10-3
1,050 = 1.05 x 103
b. Complete the conversions of simple numbers to
exponential numbers on your worksheet.
LAB #1
THE METRIC SYSTEM
1. Exercise 2F :
a. Converting exponential notation to decimal
notation
1.05 x 10-3 = 0.00105
1.05 x 103 = 1,050
b. Complete the conversions of exponential
numbers to simple numbers on your worksheet.