EOC Unit 1 Study guide
· Note: A scientific theory is an explanation that explains HOW AND WHY something occurs and is supported by ALL OF THE EVIDENCE AVAILABLE. (It is not just a “guess” or somebody’s opinion. It is what is believed to be true based on all of what we know. The only difference between a scientific theory and a scientific law is that a theory explains HOW it happens while a law just says that it does happen)
What is the difference between a hypothesis and a theory?
What is the difference between an independent variable, dependent variable, & control variable? Be sure to be able to identify each in an example experiment.
What is biology?
Practice questions:
1. In 1887 a strange nerve disease attacked the people in the Dutch East Indies. The disease was beriberi. Symptoms of the disease included weakness and loss of appetite, victims often dies of heart failure.
Find the…
independent variable: dependent variable:
2. In 1928, Sir Alexander Fleming was studying Staphylococcus bacteria growing in a culture dish. He noticed that a mold called Penicillium was also growing in some of the dishes. A clear area existed around the mold because all the bacteria that had grown in this area had died. In the culture dishes without the mold, no clear areas were present.
Fleming hypothesized that the mold must be producing a chemical that killed the bacteria. He decided to isolate this substance and test it to see if it would kill bacteria. Fleming transferred the mold to a nutrient broth solution. This solution contained all the materials the mold needed to grow. After the mold grew, he removed it from the nutrient broth. Fleming then added the nutrient broth in which the mold had grown to a culture of bacteria. He observed that the bacteria died.
Find the…
Control group:
Experimental group:
independent variable:
dependent variable:
control variables:
3. The role of a control in an experiment is to what?
4. Identify the independent & dependent variables in the following:
"There will be a statistically significant difference in graduation rates of at-risk high-school seniors who participate in an intensive study program as opposed to at-risk high-school seniors who do not participate in the intensive study program."
IV: DV:
“A nurse researcher wants to study the effects of yoga on blood pressure in hypertensive adults.”
IV: DV:
5. Explain why it is important to have a control group.
6. What are the 5 parts that must be on every graph (4 of these must be on EVERY graph while 1 of them will only be on graphs with 2 sets of data being shown)?
7. What is the SI unit for the following measurements?
a), mass, b) length, c) temperature, d) volume, e) area, f) density
8. Convert the following units:
a) 12 cm (centimeters) = ___ um (micrometers)
b) 2,604.54 Mm (megameters) = ____ km (kilometers)
c) 0.003 mL (milliliters) = ____ liters
d) 5.223 grams = ____ hg (hectograms)
9. A company believed that it may be able to generate more net profit by opening its stores at later times because they had little business in the morning (and felt like they were wasting money paying employees during this time. The company decided to do an experiment on this hypothesis by opening at a different time each day for a week. Below is a data table showing their findings:
Day # / Time store opened / Profits1 / 8 am / 10,000
2 / 9 am / 15,000
3 / 10 am / 16,000
4 / 11 am / 15,000
5 / 12 pm / 13,000
6 / 1 pm / 10,000
7 / 2 pm / 9,700
· Write a hypothesis (in proper format) for the company with regards to this experiment.
· What is the: 1) independent variable, 2) dependent variable, 3) control variables for this graph
· Graph this data (remember to put the correct variable on each axis)
· What should their conclusion be?
· If the store decided to change the prices of their merchandise each day in addition to opening at different hours, would this be acceptable (in terms of being a valid experiment)? Why / why not?
10. Calculate the mean of the following sets of value:
a) 5, 3, 4
b) 610, 610.6, 612, 616, 415
c) 0.003, 0.00004, 0.1, 1.3, 2.5