1a. Inquiry- How are plant cells visulised with a microscope?

Click on the slide and read it.

Which ONE of the following is NOT one of your Success Criteria?

• I can safely and correctly use and identify the parts of a microscope.  

• While using a microscope, I can use scientific diagram conventions to communicate what is heard.

• I have used correct scientific vocabulary in my diagrams.

• I can create wet mounts of specimens for microscopy.

Introduction: 

Outline the scientific concepts involved in your experiment.

To complete this part of the introduction, read the ‘Inquiry 1: definition of key vocabulary’. Your teacher has either given it to you or placed it on Google Classroom for you. Then, drop and drag the correct words.

​ (a)   is the scientific name for a living thing.  All living things are made of​ (b)   .   Cells are the basic unit of ​ (c)   .  Generally, cells are very​ (d)   so we can not see them without the ​ (e)   of a microscope.

​

• Organism
• cells
• life
• small
• Magnification

Introduction (continued) : 

Outline the scientific concepts involved in your experiment.

To complete this part of the introduction, read the ‘Inquiry 1: definitions of key vocabulary’. Your teacher has either given it to you or placed it on Google Classroom for you. Then, drop and drag the correct words.

​

​ (a)   is the scientific name for living things.  All living things are made of cells.   Cells are the basic unit of life.  Generally, cells are very​ small, so we can not see them without the ​magnification of a microscope. Light (b)   help us see cell specimens. Sometimes, if we stain cells with a dye, we may be able to see some basic cell structures, like the ​ (c)   and nucleus.  A very thin one-cell thick specimen of cell tissue is needed to visualise these structures. 

​

• microscopes
• cell wall
• Organism

How to Use a Compound Microscope

Safely carrying the microscope 

1. - In its box, hold the box handle with one hand and the other hand under the base of the box. 

2. - or by using one hand to grip the arm of the microscope arm (1) and the other arm under the base (2) of the microscope.  

Which two of the following statements are true?

• A microscope can be carried in it box with one hand on the handle and the other under the box.

• A microscope can be carried with one hand gripping the microscope arm.

• A microscope can be carried with one hand gripping the microscope arm and one hand under its base.

Using the microscope image

Use the information to match the names to the numbers on the microscope.

(turn on read mode in the quiz setting if needed)

1. Plug in the power cord and switch the PowerPoint on. 

2. Turn the revolving turret/nose piece (3) so that the lowest-power objective lens (4) is clicked into position. Lens magnifications are on the side of the lens; usually, the lowest-power objective is 4x.

3. Place the microscope slide on the stage (5) and fasten it with the stage clips (if your microscopes have them).

4. Look at the objective lens (4) and the stage from the side and turn the focus knob (6) so the stage moves upward. Move it up as far as it will go without letting the objective touch the coverslip.

5. Look through the eyepiece (7) and move the focus knob until the image comes into focus.

6. Adjust the diaphragm (8) and light intensity (9) for the most light.

7. Move the microscope slide around until the sample is in the centre of the field of view (what you see?).

8. Use the focus knob (6) to place the sample into focus and readjust the condenser (8) and light intensity (9) for the clearest image (with low power objectives, you might need to reduce the light intensity or shut the condenser).

9. You can change to the next objective lens when you have a clear sample image with the lowest power objective. You should readjust the sample into focus (slightly) and/or readjust the condenser and light intensity. If you cannot focus on your specimen, repeat steps 4 through 6 with the higher power objective lens in place. Do not let the objective lens touch the slide!

10. Repeat step 9 if you are going to an even higher power objective. 

11. When finished, lower the stage, click the low-power lens into position and remove the slide.

• 6

• focus knob

• 4

• turret/nose piece

• 3

• objective lens

• 5

• stage

Using the microscope image

Use the information to match the names to the numbers on the microscope.

(turn on read mode in the quiz setting if needed)

1. Plug in the power cord and switch the PowerPoint on. 

2. Turn the revolving turret/nose piece (3) so that the lowest-power objective lens (4) is clicked into position. Lens magnifications are on the side of the lens; usually, the lowest-power objective is 4x.

3. Place the microscope slide on the stage (5) and fasten it with the stage clips (if your microscopes have them).

4. Look at the objective lens (4) and the stage from the side and turn the focus knob (6) so the stage moves upward. Move it up as far as it will go without letting the objective touch the coverslip.

5. Look through the eyepiece (7) and move the focus knob until the image comes into focus.

6. Adjust the diaphragm (8) and light intensity (9) for the most light.

7. Move the microscope slide around until the sample is in the centre of the field of view (what you see?).

8. Use the focus knob (6) to place the sample into focus and readjust the condenser (8) and light intensity (9) for the clearest image (with low power objectives, you might need to reduce the light intensity or shut the condenser).

9. You can change to the next objective lens when you have a clear sample image with the lowest power objective. You should readjust the sample into focus (slightly) and/or readjust the condenser and light intensity. If you cannot focus on your specimen, repeat steps 4 through 6 with the higher power objective lens in place. Do not let the objective lens touch the slide!

10. Repeat step 9 if you are going to an even higher power objective. 

11. When finished, lower the stage, click the low-power lens into position and remove the slide.

• 6

• eyepiece

• 9

• light intensity

• 7

• focus knob

• 8

• diaphragm

This experiment asks the question:

How are plant cells visualised with a light microscope?

The method takes two very thin pieces of onion bulb tissue (see image) and stains one with a blue dye, and the other is left unstained to see which method helps us visualise the onion cells best using a light microscope.

With this information, write an aim for this experiment.

Eg. The aim of the experiment is .....

In an experiment, many things can change; these are called variables because they vary.

You only change one variable to ensure the investigation will lead to reliable (good) results.

The variable that you change is called the independent variable.

From what you know of this experiment, what is being changed (independent variable) between the two onion samples being made?

• Whether the dye stain is on the sample or not.

• The type of plant sample.

• The equipment we used to view the sample.

In an experiment, the stained and unstained tissue sample (a specimen) will be viewed using a microscope to magnify what is seen. We might expect the stain to affect what can be seen in the samples, and we will 'measure' by drawing the differences in a scientific drawing.

The independent variable (the thing that is changed) in this experiment is the + or - staining of the sample.

A dependent variable is the thing that you measure in an experiment.

Select the dependent variable in this experiment.

• Whether the dye stain is on the sample or not.

• The type of plant sample.

• What is seen using the microscope and represented (drawn) in a scientific diagram.

In science, when we run experiments, we make educated predictions about what will happen in the experiment. This is called a hypothesis. We then test the hypothesis. Is it right or wrong?

A hypothesis should include the independent variable (what we change ), the dependent variable (what we measure), and the expected change.

Which of the following is a reasonable hypothesis for this experiment?

• If the onion tissue is stained, then the tissue structure will be more clearly visulised when using the mocroscope.

• The tissue is stained and the sample is viewed under the microscope.

• The sample will be visulised using a microscope and the results will be recorded in scientific diagrams .