Mr. PorubanChapter 2: Laboratory SkillsGenetics/Biotechnology

Laboratory Safety

Learning how to work in a safe laboratory environment is the goal of this section. You must read and learn the proper safety protocol and achieve at least a 90% on the safety quiz before you will be able to perform any laboratory experiments in this course!

  1. What does PPE stand for? Give several examples of what type of PPE you will be using in a biotechnology laboratory.
  1. What is a MSDS for and what does it contain?
  1. Name and describe each of the biological laboratory classifications. (BSL1-BSL4)

Laboratory Notebooks

You will be given a laboratory notebook to use in this course. We will review and practice this throughout the course and you will receive several grades based on a properly written laboratory notebook.

  1. Read pages 25-26 in order to get a good background on how you should structure your notebook. Outline the key features for notebook structure and components of a notebook entry.

Laboratory Equipment

Learning how to identify and use laboratory equipment is the goal of this section. You must be able to identify and use each piece of equipment properly and achieve at least a 90% on the equipment quiz before you will be able to perform any laboratory experiments in this course!

  1. Using the proper laboratory notebook technique, complete the following in your lab notebook:
  2. Draw and identify all equipment that can measure volume, mass, temperature and contain liquids.
  3. List the procedures for proper glassware washing.
  4. List proper labeling technique.

Numerical Data

Significant Figures: The digits that contribute to the precision of the instrument being used.

The following rules can be used when determining the number of significant digits in a number:

Rule / Example / Sig Digs
1. All nonzero numbers are significant. / 132.54 g / 5
2. All zeros between nonzero numbers are significant. / 130.0054 m / 7
3. Zeros to the right of a nonzero digit but to the left of an understood decimal point are not significant unless shown by placing a decimal point at the end of the number. / 190 000 mL
190 000. mL / 2
6
4. All zeros to the right of a decimal point but to the left of a nonzero digit are NOT significant. / 0.000 572 mg / 3
5. All zeros to the right of a decimal point and to the right of a nonzero digit are significant. / 460.000 dm / 6

You can remember these rules or learn this very easy shortcut:

If the number contains a decimal point, draw an arrow starting at the left through all zeros and up to the 1st nonzero digit. The digits remaining are significant.

Try these:

0.002 51.002 50.002 500 014 100.0

If the quantity does not contain a decimal point, draw an arrow starting at the right through all zeroes up to the 1st nonzero digit. The digits remaining are significant.

Try these:

22510 00414 100103

A good way to remember which side to start on is:

decimal point present, start at the Pacific

decimal point absent, start at the Atlantic

Practice Section - How many significant digits do each of the following numbers have?

1. 1.050______6. 420 000______

2. 20.06______7. 970______

3. 13______8. 0.002______

4. 0.303 0______9. 0.007 80______

5. 373.109______10. 145.55______

Numerical data (continued)

Applying significant digits to arithmetic operations

Addition and Subtraction – Look at the numbers being added or subtracted and identify which one has the lowest number of decimal places. Calculate the answer. Round the answer to the lowest number of decimal places.

14.565 + 7.32 = 21.885

7.32 has only 2 decimal places, so the answer should be rounded to 21.88

143.52 – 100.6 = 42.92

100.6 has only 1 decimal place, so the answer should be rounded to 42.9

Multiplication and Division – Look at the numbers being multiplied or divided and identify which one has the lowest number of significant digits. Calculate the answer. Round the answer to the lowest number of significant digits.

172.6 x 24.1 = 4159.66

24.1 has only 3 significant digits, so the answer should be rounded to 4160

172.6 ÷ 24.1 = 7.161 82

24.1 only has 3 significant digits, so the answer should be rounded to 7.16

Practice Section - Express each answer with the correct number of significant digits.

1

  1. Add 5.34 cm, 9.3 cm, and 12 cm.
  1. Subtract 4.31 cm from 7.542 cm.
  1. Subtract 1.512 g from 16.748 g.
  1. Add 2.572 5 m, 14.55 m and 0.035m.
  1. Multiply 176.335 and 0.003 2.
  1. Divide 475.90 by 35.
  1. Multiply 0.000 565, 1.579 52, and 45.006 86.
  1. Multiply 1 456.00 by 0.035 0 and divide that by 17.070.

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Scientific Notation:

Scientific notation has been developed to make numbers easier to read and communicate the level of precision at which the numbers were recorded. For example, the speed of light is 300 000 000 m/s. A simple way to write this number is 3 x 108.

Start your practice with the number 500 000 000. Move the decimal point until you have only one nonzero digit to the left of the decimal point remaining. It is 5. Count the number of places that you moved the decimal point. In this case it was 8 places. This is the number that you place as the exponent to your base 10. The number is written as 5 x 108.

Another example: 0.007 67 written in scientific notation is 7.67 x 10-3.

WHEN YOU MOVE THE DECIMAL POINT OT THE LEFT, a IS A POSITIVE NUMBER

WHEN YOU MOVE YOUR DECIMAL POINT TO THE RIGHT, a IS A NEGATIVE NUMBER

Practice Section -Write the following in scientific notation.

1. 12 300______5. 6.650 x 102 ______

2. 1 456______6. 3.498 x 105______

3. 0.005 17______7. 2.208 x 10-3______

4. 0.000 6______8. 1.1650 x 10-4______

Preparing Solutions

Notes will be given on this section:

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