Do Now: Read the paragraph and answer the two questions below. What causes fatigue? A condition know as muscle fatigue occurs when certain waste products

Do Now: Read the paragraph and answer the two questions below.

What causes fatigue?A condition know as muscle fatigue occurs when certain waste products of muscle cell activity build up in the cells. Until these waste chemicals are removed, the fatigue will continue.

•What is another word to describe “fatigue”?

•Why “rest” help recover from fatigue?

Objective: How Does Fatigue Affect Muscle Performance?Key Words: fatigue, squeeze, homeostasis, claim, evidence, fact

Tiredness

Rest allows the body to remove waste chemicals from cells

Do the Following Activity

• Hold a spring-type clothespin between your thumb and index finger.

• Pinch the ends together completely (until the two ends touch) and release them.

• Do this as rapidly as possible for one minute.

• Record the number of times you could squeeze the clothespin in one minute: __________

• Try the activity again, doing it the same way and using the same two fingers as before.

• Record the number of times you could squeeze the clothespin the second time:__________


Answer the Following Questions

1. Some people are able to squeeze the clothespin more times in a minute than others. Suggest a possible explanation for this.

2. Could you do as many in a minute the second time as you could do the first time?Provide a biological explanation for these results

Having stronger muscles or better fine motor skills

If yes, first time squeezing the clothespin increased pulse rate, then second timemuscles gets more oxygen and nutrients, and have more energy.

OR

If not, first time squeezing took energy away for the muscles, then second timemuscles gets less oxygen and nutrients, and have less energy.



1. What does an increased pulse rate indicate about the heart rate and flow of blood in someone’s body?

An increased pulse rate indicates that the heart will beat faster so the blood will flow more rapidly

2. When muscles are active, cells use nutrients and oxygen at a higher rate andproduce waste chemicals and heat more rapidly. Describe how the interaction of two or more body systems helps to maintain homeostasis during periods of high muscle activity.

The circulatory system: the heart pumps faster, so more glucose and nutrients will be delivered to the muscles.

The respiratory system: the lungs breathe more rapidly, so more oxygen is takingin and carbon dioxide taking out.

Part A. Questions


3. A student in your class suggests that when most people watch exciting sporting events on television, their pulse rates increase. What is a reliable way to find out if this statement is correct?

By designing a control experiment or an investigation

4. What specific evidence would you need in order to determine if what the student suggests in question #3 can be supported?

You need to measure the pulse rate in different scenarios:a. When people are watching exciting sporting events on TVb. When people watch other kinds of programs on TV


5. If you wanted to increase your clothespin-squeezing rate, would you suggest exercising or resting before you did it? Explain why you think your choice is the correct one

I would suggest exercise first because it produces a faster pulse rate, which indicates that the blood is getting to the muscles faster.

OR

I would suggest relax first because exercise takes energy away from the musclesand a person who has been resting will have more energy.


Investigating Claims Student A claims that a person will be able to squeeze a clothespin more times in a minute if the person exercise first. Student A suggests that exercising produces a faster pulse rate, which indicates that the blood is getting to the muscles faster. Student B claims that a person will be able to squeeze the clothespin more times in a minute if the person does not exercise first. Student B suggests that exercise takes energy away from the muscles, and a person who has been resting will have more energy. •Which of the two students do you agree with?_______

•How could you find out for sure which claim is correct?

By designing a control experiment or an investigation

Objective: Design an Investigation to Support or Refute a ClaimKey Words: Claim, evidence, fact, hypothesis, variable

• You must now design and conduct a controlled experiment to gather evidence that will determine which of the two claims is correct. • Be sure your experimental methods will provide enough data upon which to base a valid conclusion. • You will have to conduct several trials.• Your report must include the following parts.


Design an Experiment

• Student B:What is the effect of _______________

on _____________________________?

• Determine the question you are trying to answer• Use the format: “What is the effect of ___________

on _____________________?”

1. Problem


• Student A:What is the effect of _______________on _____________________________?

exercise firstclothespin squeezing rate

resting firstclothespin squeezing rate

2. Hypothesis

Student A:

If somebody exercises first

then she will increase the clothspin squeezing rate

• The hypothesis is a tentative statement about the expected relationship between the variables. • Use the format: “If _____________________________

Then ___________________________”

Student B:

If somebody rests first

then she will increase the clothspin squeezing rate


3. Variables

• The independent variable is ____________________________

• The dependent variable is ______________________________

exercise first / resting first

clothespin squeezing rate

• Your independent variable is the variable you chose to test in your experiment.• Your dependent variable is the variable you measure in your experiment.


•Explicit the independent and dependent variables. (10 credits)

• Your independent variable is the variable you chose to test in your experiment.

• Your dependent variable is the variable you measure in your experiment.

•Describe your experimental group in at least four steps. (10 credits)

•Describe your control group in at least four steps. (10 credits)

• Decide how many individuals you will test,• What you will have them to do• How many trials you will conduct with each• How the control and experimental group differ

•List the materials you need to conduct your experiment (5 credits)


4. Design of the Experiments

4. Design of the Experiments

Experimental Group1. Take ____students. 2. Let them exercise first by (doing something)___ for (how long)___3. Ask them to hold a clothespin between their right thumb and index

finger. Ask them to pinch the ends together and release them.4. Count ______________________________________________5. Rest for _____ minutes.6. Repeat the experiment _______times.

Control Group1. Take ____students. 2. Let them rest first for (how long) ________________3. Ask them to hold a clothespin between their right thumb and index

finger. Ask them to pinch the ends together and release them.4. Count ______________________________________________5. Rest for _____ minutes.6. Repeat the experiment _______times.


5. Observation Data table

Control Group: Clothespin Squeezing Rate after _______________Student’s

Name

Trial #1 Trial #2 Trial #3 Average

Design a data table to record your observations

Experimental Group: Clothespin Squeezing Rate after __________Student’s

Name

Trial #1 Trial #2 Trial #3 Average


6. Observations

• Organize and graph your data using a line graph

Students

Ave

rage

Clo

thes

pin

Squ

eezi

ng R

ate

(tim

es/m

in)

Edwin Lin Han Adeb

After Exercise

After Resting

Average Clothespin Squeezing Rate of Students in class


7. Conclusion

• Review your hypothesis

• Explain your conclusion based on your observations and your knowledge.

• This investigation has been performed by….

• My hypothesis is (true or false).• According to my data _____________________________• One possible explanation of my conclusion is __________


ItemsYour Grade

Teacher’s Grade

1. Problem: Over 10 credits, you got:

The problem clearly determined the question you are trying to answer. The problem is stated using the format: “What is the effect of ___ on __________?”2. Hypothesis: Over 10 credits, you got:

The hypothesis is a tentative statement about the expected relationship between the variables. The hypothesis uses the format: “If _______________ then _______________________”

3. Design of your experiment: The independent variable is explicitly included (5 credits) The dependent variable is explicitly included. (5 credits) The experimental group is described in at least four steps. (10 credits) The control group is described in at least four steps. (10 credits) Both groups include

How many individuals you will test What you will have them to do How many trials you will conduct with each

The materials you need to conduct your experiment are listed (5 credits) Observation:

Design one o more data tables that you will use to record the data (10 credits) Plot your data in a bar-graph to summarize the data for easier understanding of what you found (10

credits)

State a conclusion: Note whether you data supports or refuse your hypothesis (5 credits)

Include an explanation of how or why this conclusion follows from the data you collected. (5 credits)

Presentation: The report is clear and concise, well written in proper English ( 10 Credits) The presentation is neat and creative (5 credits)

Making Connection Lab - Rubric

Your total grade is


1.Correctly state the problem being debated in this research. Remember this needs to be in the form of a question.

What is the effect of doing 50 jumping jackson the rate of squeezing a clothespin in one minute?

2. Using the correct format for stating a hypothesis, correctly state a hypothesis for this experiment.

If I do 50 jumping jacksThen I will squeeze a clothespin more times in one minute


3. Design a procedure using a minimum of five steps that could test this proposal.

Experimental group:1. Collect the materials: clothespins and stop watchers.2. Ten people do 50 jumping jacks3. They squeeze a clothespin for a minute4. They measure the number of times they pinch the clothespin5. Repeat the experiment 5 times and calculate the average

Control group6.The same procedure as before, but they rest before squeezing


4. Explain what is meant by the independent variable

Independent variable is the variable you choose or test in the experimental group

5. What is the independent variable in this experiment?

The independent variable is to do 50 jumping jacks

6. Explain what is meant by the dependent variable

Dependent variable is the variable you measure in both the experiment and control groups.

7. What is the dependent variable in this experiment?

Dependent variable is the number of time people squeeze a clothespin in one minute


8. Explain what is meant by a control

Control is the experiment set up without independent variable.

9. What is the control in this experiment?

The control is the experiment in which people relax before squeezing

10. State or present data that will support your hypothesis for this experiment. Draw a data table if you wish

Groups Control Experimental Group

1

2

3

4

Average

People who did jumping jacks before squeezing were able to squeeze ____ times (___) than people who rested before squeezing (___)


4. Conduct your experiment (5 credits)• Gather the materials you will need, arrange for your “test subjects” and do

the experiment 5. Observation: Data table & Graph (20 credits)

• Design one o more data tables that you will use to record the data (10 credits) • Plot your data in a bar-graph to summarize the data for easier understanding

of what you found (10 credits) 6. State a conclusion (10 credits)

• Note whether you data supports or refuse your hypothesis• Include an explanation of how or why this conclusion follows from the data

you collected.• The report is well written in proper English (10 Credits)


Documents

Do Now: Read the paragraph and answer the two questions below. What causes fatigue? A condition know as muscle fatigue occurs when certain waste products