I.
What is Science?
a. Your definition:
II.
What is biology? (Why is this class called Living Environment?)
b.
Your partner’s definition:
a.
Study of living things
c.
Our class definition: b.
Living Environment focuses more on the Living part of biology (ecology, cells, genetics, evolution) than on other things such as biochemistry and all of the human body systems in detail
A body of knowledge and a way of doing things; we learn about how the world works through intellectual and social activities.
III. What is scientific inquiry?
a. Your definition:
b. Your partner’s definition:
c.
Our class definition: Asking a question about the world and finding out an answer or explanation
V. What does scientific inquiry involve?
a. Asking questions b. Observing and inferring
c. Experimenting
d. Collecting and organizing data
e. Finding evidence and drawing conclusions
f. Repeating the experiment several times
g. Peer review
IV. What is the purpose of scientific inquiry?
a. To develop explanations of natural phenomena in a continuing and creative process.
Also…
h. locating, interpreting, and processing information from a variety of sources
i.
making judgments about the reliability of the source and relevance of information
i.
What makes a source reliable?
VI. Scientific Explanations
a. Built by combining evidence that can be observed with what people already know about the world.
b. Scientific explanations are accepted when they are consistent with experimental and observational evidence and when they lead to accurate predictions.
Observation = any information that is collected with any of the senses
i.
All scientific explanations are tentative and subject to change or improvement.
c.
ii. Inference = conclusion or deduction based on observations
d. Each new bit of evidence can create more questions than it answers. This leads to increasingly better understanding of how things work in the living world.
1. Assumptions = belief that something is true
2. Bias = influenced by an assumption that may or may not be correct
e. History… Learning about the historical development of scientific concepts or about individuals who have contributed to scientific knowledge provides a better understanding of scientific inquiry and the relationship between science and society.
i.
Who is a scientist that you know about? What is he/she famous for?
f.
Values… Science provides knowledge, but values are also essential to making effective and ethical decisions about the application of scientific knowledge.
i.
Ethical = moral, the good choice
ii. What are some of your values?
iii. What are some things you would value when conducting research?
VII. Theories
a. Well‐accepted theories are ones that are supported by different kinds of scientific investigations often involving the contributions of individuals from different disciplines.
i.
Theory = An explanation, supported by many observations and/or experiments, that can be used to accurately explain related occurrences
VIII. Research/Experimentation
a. Hypotheses… are predictions based upon both research and observation.
i.
usually written as an "if"..."then"...statement
ii. Hypotheses are widely used in science for determining what data to collect and as a guide for interpreting the data.
ii. Development of a research plan for testing a hypothesis requires planning to avoid bias (e.g., repeated trials, large sample size, and objective data‐collection techniques).
iii. Control = established reference point used as a standard of comparison
b. Experimentation… doing the actual experiment to test (support or refute) your hypothesis
i.
iv. Controlling the experiment = keeping everything else the same in an experiment so that there is only ONE independent variable
Independent variable = variable I can change
1. You should only have ONE independent variable
2. Examples: amount of sunlight, amount of water, taking medicine
1. Ex: test the effect of sunlight on plant growth: keep temp., water, soil the same
ii. Dependent variable = data that you collect, depends on the independent
1. Is recorded in a table and then put into a graph
2. Ex: plant growth
v. Collecting/organizing data 1. Make a chart or table or drawing
ii.
c.
Analysis… The observations made while testing proposed explanations, when analyzed using conventional and invented methods, provide new insights into natural phenomena.
i.
Organizing data 1. Plot data into a graph when necessary (either bar or line)
Interpretation of data leads to development of additional hypotheses, the formulation of generalizations, or explanations of natural phenomena.
1.
Hypotheses are valuable, even if they turn out not to be true, because they may lead to further investigation.
2.
Claims should be questioned if the data are based on samples that are very small, biased, or inadequately controlled or if the conclusions are based on the faulty, incomplete, or misleading use of numbers.
3.
Claims should be questioned if fact and opinion are intermingled, if adequate evidence is not cited, or if the conclusions do not follow logically from the evidence given.
Lab Skills...
d.
Results… Scientists make the results of their investigations public; they should describe the investigations in ways that enable others to repeat the investigations.
i.
Draw a conclusion – a decision about the outcome
ii.
Scientists use peer review to evaluate the results of scientific investigations and the explanations proposed by other scientists. 1. analyze the experimental procedures
2. examine the evidence
3. identify faulty reasoning
4. point out statements that go beyond the evidence
5. suggest alternative explanations for the same observations.
I. Measuring Length a. Use a metric ruler
length = 2.59 cm ­ 0.51 cm
= 2.08 cm
II.
III. Measuring Temperature
a. Always use Celsius
Measuring Volume
a.
b.
c.
Use a graduated cylinder for liquids
i. Read the bottom of the meniscus
IV. Measuring Mass – amount of matter in something
a. Use a balance or electronic scale
b. We don’t “weigh” things Use a metric ruler for solids
volume = 43.0 mL
Use water displacement for irregular solids
1
1,600
1000
kilo
hecto
deca
14,000
deci
0.25
0.109
centi
milli
put into the same unit to compare
>
<
"King Henry Died By Drinking Chocolate Milk"
2
kg
mL
m
g
mm
L
5,000
160
km
cm
mg
104,000
0.198
2.5
4.8
0.075
65,000
5,600
0.5
63
560
0.120
0.8
<
=
>
=
<
>
skip: Metric system challenge & What is a hypothesis?
Page 6
Smithers thinks that a special juice will increase the productivity of workers. He creates two groups of 50 workers each and assigns each group the same task (in this case, they're supposed to staple a set of papers). Group A is given the special juice to drink while they work. Group B is not given the special juice. After an hour, Smithers counts how many stacks of papers each group has made. Group A made 1,587 stacks, Group B made 2,113 stacks.
Identify the:
1. Control Group
Group B
2. Independent Variable
special juice
3. Dependent Variable productivity (how many stacks made)
4. What should Smithers' conclusion be?
The juice does not increase productivity of workers. The juice seems to decrease productivity of workers.
5. How could this experiment be improved?
­ repeat experiment (more trials)
­ test more people (larger sample size)
Bart believes that mice exposed to radio waves will become extra strong (maybe he's been reading too much Radioactive Man). He decides to perform this experiment by placing 10 mice near a radio for 5 hours. He compared these 10 mice to another 10 mice that had not been exposed. His test consisted of a heavy block of wood that blocked the mouse food. He found that 8 out of 10 of the radio waved mice were able to push the block away. 7 out of 10 of the other mice were able to do the same. Homer notices that his shower is covered in a strange green slime. His friend Barney tells him that coconut juice will get rid of the green slime. Homer decides to check this out by spraying half of the shower with coconut juice. He sprays the other half of the shower with water. After 3 days of "treatment" there is no change in the appearance of the green slime on either side of the shower.
6. What was the initial observation?
Homer's shower was covered in green slime.
Identify the­
7. Control Group
half of shower sprayed with water
8. Independent Variable
coconut juice
9. Dependent Variable
how much green slime there is
Identify the­
11. Control Group
13. Dependent Variable
10. What should Homer's conclusion be?
Coconut juice has no effect on the green slime.
v v
Krusty was told that a certain itching powder was the newest best thing on the market; it even claims to cause 50% longer lasting itches. Interested in this product, he buys the itching powder and compares it to his usual product. One test subject (A) is sprinkled with the original itching powder, and another test subject (B) was sprinkled with the Experimental itching powder. Subject A reported having itches for 30 minutes. Subject B reported to have itches for 45 minutes. Identify the­
16. Control Group
17. Independent Variable
18. Dependent Variable
mice not exposed to radio waves
12. Independent Variable
type of itching powder
length of itching
19. Explain whether the data supports or refutes the advertisements claims about its product.
Supports ­ the Experimental itching powder cause itching for 50% longer than the other brand
ability to push block to get food
14. What should Bart's conclusion be?
Exposing mice to radio waves has no effect on their strength.
15. How could Bart's experiment be improved? repeat experiment (more trials)
test more mice (larger sample size)
Lisa is working on a science project. Her task is to answer the question: "Does Rogooti (which is a commercial hair product) affect the speed of hair growth". Her family is willing to volunteer for the experiment. 20. Describe how Lisa would perform this experiment. Identify the control group, and the independent and dependent variables in your description.
Independent variable: Group A ­ original itching powder
exposure to radio waves
Using Rogooti
Dependent variable: Speed of hair growth
Control group:
Two people who do not use Rogooti
Experimental design:
Everyone's hair length is measured before starting the experiment. Group A (control) does not use Rogooti for 1 week, while Group B (experimental) uses Rogooti for 1 week. After 1 week, everyone's hair length is measured again. Repeat for several weeks. Laboratory Equipment
tongs
test tube
graduated cylinder
Bunsen burner
Erlenmeyer flask
ring stand
funnel
beaker
balance
Attachments
imgres