Practice of Science --- Day 4 (Wheatgrass Investigation)

Practice of Science --- Day 4

* Students will be able to define a problem, plan and carryout investigations of various types, identify and explain a control group, and differentiate between an experiment and other types of scientific investigations.

Get ready to take some NOTES!

​PLAN and CARRY OUT INVESTIGATIONS

​I. Observations need to be as PRECISE as possible

• EMPERICAL DATA - measurable observations

  • E.D. forms the basis for most scientific investigation

​copy down in notebooks!

Multiple Choice

Four students are discussing the plants they are growing in class. Which of the following statements is the BEST example of an scientific observation?

• “The plants are pretty.”

• “Plants need water every day.”

• “Plants produce their own food from sunlight, carbon dioxide, and water.”

• “Plant number 3 is 17 cm tall.”

Multiple Choice

After conducting research into the growth of plants, students are ready to begin planning their investigation. Which of the following would NOT be a step in planning an investigation?

• deciding what material are needed

• deciding how much water each plant will get

• deciding how many days the investigation should last

• measuring the height of the plant

​Scientists never set out to “prove an idea."

• Let us begin with three problem statements:

  • Is more sunlight or less sunlight the best condition for growing a plant?

  • Is more water or less water the best condition for growing a plant?

  • Is more air or less air the best condition for growing a plant?

​ Now we are ready to choose one question to investigate. For the purposes of scientific investigation, the investigation should focus on only one question.

​Is more sunlight or less sunlight the best condition for growing wheatgrass?

​For this investigation, we will need the following materials:

wheatgrass seeds

potting mix

a 4”planter

a 10oz measuring cup

a centimeter ruler

PROCEDURE​ for WHEATGRASS INVESTIGATION

• The seeds will be planted in a 4” planting cup with potting soil.*

• The same amount of water will be added to each plant each day.

• The date and time will be recorded each time the plant is watered.

• The amount of water will also be recorded.

• When the plant begins to grow, the height of the plant will be measured and recorded in centimeters.

• The investigation will be conducted for two weeks.​

Multiple Choice

Students are conducting an investigation to determine the effect of soil type on the rate of growth of a plant. Which of the following would be the BEST example of a part of the investigation students would conduct each day?

• measuring and recording the height of each plant

• watching a video to help them understand the needs of plants

• reading a passage about how plants make their own food

• having a discussion about the parts of a plant

Multiple Choice

Observations are made using the five senses, and empirical observations are made using tools to make measurements. Which of the following is NOT an example of an observation students might make during an investigation of plant growth?

• plant is 14 cm tall

• 20 ml of water was added to the plant

• the water was warm

• the water was 30 degrees Celsius

Scientific Tool Used	What is being Measured?	​What unit of Measurement is used?	​How is the measurement written?
​Thermometer	​Temperature	​Degrees Celcius/Fahrenheit	​34ºC/34ºF
​Ruler	​Length	​Meters	​27m
​Measuring Cup	​Volume	​Cubic Millimeters	​77mm³
​Digital Scale	​Mass	​Grams	​413g
​Spring Scale	​Force	​Newtons	​5N

​TOOLS for OBSERVING

Match

Match the following!

• temperature

• length

• volume

• mass

• force

Thermometer

Ruler

Measuring Cup

Digital Scale

Spring Scale

• Thermometer

• Ruler

• Measuring Cup

• Digital Scale

• Spring Scale

Match

Match the following

• Degrees Celcius/Fahrenheit

• ​Meters

• Cubic Millimeters

• Grams

• Newtons

34ºC/34ºF

27m

77mm³

413g

5N

• 34ºC/34ºF

• 27m

• 77mm³

• 413g

• 5N