Making connections

An investigation is carried out to determine the effect of exercise on the rate at which a person can squeeze a clothespin. In this investigation, the independent variable is the

• control

• exercise

• rate of squeezing

• number of participants

An investigation is carried out to determine the effect of exercise on the rate at which a person can squeeze a clothespin. Muscle fatigue occurs during this activity when

• carbon dioxide is used up in the muscle cells

• simple sugar is converted to starch in the muscle cells

• proteins accumulate in mitochondria in the muscle cells

• certain waste products collect in the muscle cells

Tags

NGSS.MS-LS1-3

NGSS.MS-LS1-7

An investigation is carried out to determine the effect of exercise on the rate at which a person can squeeze a clothespin. The experimental results could be made more valid by (choose 2)

• increasing the number of students

• using safety precautions

• using a plastic clothespin

• making a bar graph of the data

  
  

• repeating the experiment

An investigation is carried out to determine the effect of exercise on the rate at which a person can squeeze a clothespin. The dependent variable for this experiment is the

• time the student was squeezing the clothespin

• number of times the student was able to squeeze the clothespin

• strength of the student

• length of the clothespin

Tags

NGSS.MS-PS2-2

A student lifted weights after school and found that his muscles started to burn. He couldn’t continue to lift the weights after prolonged exercising. This muscle fatigue is most likely due to

• the heart beating too fast and tiring out

• the lungs accumulating oxygen

• lack of oxygen and build up of waste in the muscles

• lack of carbon dioxide in the muscles

Tags

NGSS.HS-LS1-7

NGSS.HS-LS2-3

If a control group is not included in an experiment, it would be difficult to

• formulate a hypothesis for the experiment

• make observations about the experimental group

• record data in a data table

• draw a valid conclusion

A class is recording pulse rates of the students in a data table like the one shown.

One student checks his pulse and counts 23 beats over a time interval of 20 seconds. In which row in the data table should the pulse rate of this student be recorded?

• A

• B

• C

• D

What is the function of the circulatory system?

• Transport oxygen and nutrients

• Remove extra water and wastes

• Digest food and absorb nutrients

• Collect, transfer and process information

Which body system gets oxygen from the environment and removes carbon dioxide and other wastes from the body?

• Circulatory
• Respiratory
• Digestive
• Excretory

Which system transports materials from the digestive system and respiratory system to the cells?

• circulatory
• respiratory
• digestive
• skeletal