BIOLOGY TAKE OUT NOTEBOOKS

LAB SAFETY

•HW: Get Lab Safety contract signed•Get HR Paperwork signed•Go to all class websites and sign in or

create a password.

Lab Safety Challenge #1

T. Trimpe 2008 http://sciencespot.net/

What’s wrong? Identify 6 different safety concerns shown in the picture below.

Image: http://morrisonlabs.com/lab_safety.htm

The answers are …

Image: http://morrisonlabs.com/lab_safety.htm

Don’t eat or drink while in the lab.

Don’t fool around during a lab.

Always wear safety goggles when doing an experiment

Always point test tubes and other items away from yourself and others when heating.

Keep hair and other flammable objects away from flames.

Don’t leave a flame unattended.

Lab Safety Challenge #2

T. Trimpe 2008 http://sciencespot.net/

What’s wrong? Identify 9 different safety concerns shown in the picture below.

Image: http://morrisonlabs.com/lab_safety.htm

The answers are …

Image: http://morrisonlabs.com/lab_safety.htm

Always wear safety goggles during a lab.

Don’t leave materials laying on the floor. Clean up spills immediately

Don’t heat closed containers.

Keep your lab area neat and clean.

Unplug equipment when not in use.

Don’t place lab materials near the edge of the table.Keep papers and other flammable

objects away from flames.

Don’t smell directly from a container - WAFT.

THE GOAL OF SCIENCE :

• To investigate and understand the world around us.• To explain events in the natural world• To use those explanations to make useful

observations. Science is an organized way of using evidence to learn about the natural world.

SCIENTIFIC RESEARCH/THOUGHT INCLUDES• Observation – The process of gathering information

called data. • Two types of data: • Quantitative – can be counted or

measured/numbers• Qualitative- descriptive, cannot be counted

SCIENTIFIC RESEARCH/THOUGHT INCLUDE

• Inference- a logical interpretation based on prior knowledge or experience• Hypothesis- a proposed scientific explanation for a set of

observations (educated guess) • Science knowledge is always changing (an ongoing

process)

DESIGNING AN EXPERIMENT

1. Ask a question2. Form a hypothesis (make observation) 3. Set up a controlled experiment• Variable- factor in an experiment that is changed• An experiment should contain only one variable. • All other variables/factors should be controlled (unchanged). • Called a controlled experiment

DESIGNING AN EXPERIMENT CONTINUED

• Manipulated variable- (independent variable) factor that is deliberately changed. • Responding variable- (dependent variable) factor that changes

in response to the manipulated variable, it is observed. 4. Record and analyze results5. Draw conclusions (could refute hypothesis)

KEY BIOLOGICAL EXPERIMENTS

• Ignaz Semmelweis - Germ Theory• Franceso Redi and Louis Pasteur- Spontaneous

generation• Hershey- Chase Experiment- DNA carries genetic

information

WHEN EXPERIMENTS ARE NOT POSSIBLE:

• Field studies: observe animals in the wild• Population samples (large groups give more reliable

results) • Theory- A well tested hypothesis, always with the same

result. • Biogenesis- generating life from life.