What is a stimulus? Lesson 3

What is a Stimulus?
By Rahan Rahman

​Learning intentions

Success: Students will define what a stimulus and a response is.

Stretch: Students will define what a stimulus and a response is while providing examples.

Challenge: Students will define what a stimulus and a response is while providing examples. Students can also conduct an experiment showcasing a stimulus and response

​Success Criteria

​What is a stimulus?

A stimulus is a change or signal in the organisms environment, that an organism can react to.

An action done in response to the stimulus, is called a response.

All organisms, animals, plants and bacteria can react to a range of stimulus.

How do we detect a stimulus?

We can detect a stimulus through different types of cells in our body:

uOlfactory cells - Reacts to smells

uHair cells - Reacts to vibrations

uTaste receptors - Reacts to chemicals

uPhotoreceptors - Reacts to light

uThermoreceptors - Reacts to temperature

uMechanoreceptors - Reacts to Pressure

Drag and Drop

A

Placeholder

is a change in the environment that an organism can react to

Drag these tiles and drop them in the correct blank above

Stimulus

Response

Reaction

Amendment

System

Multiple Choice

All organisms including plants, animals and bacteria can respond to a stimulus

• True

• False

Match

Match the following

• smell

• vibration

• chemical

• light

• temperature

olfactory cell

hair cell

taste receptor

photoreceptor

thermoreceptor

• olfactory cell

• hair cell

• taste receptor

• photoreceptor

• thermoreceptor

​Reaction time Practical

In todays lesson, we will be creating our own experiment by measuring our reaction time.

But first we need a hypothesis!

Here are some suggestions:

​Choosing a hypothesis

- Do gamers have faster reaction time then non gamers
- Do boys have a faster reaction time then girls
- Do girls have a faster reaction time then boys?
- Does reaction time get slower as you age?
- Do people that are left handed have a faster reaction time than people who are right handed?

Poll

Choose your hypothesis

• Gamers

• Gender

• Age

• Left/Right handed

​Creating the experiment

Now that we have chosen our hypothesis lets set up our experiment.

On the board we will now plan our experiment

​Gathering the data

Head on over to the following site: https://humanbenchmark.com/tests/reactiontime

Do the test 3 times making sure to record your result each time.

After, calculate your average time by adding your 3 scores toghether and dividing by 3.

Record your average time.

Open Ended

Record your average time in the response below

​The Results

Record the results on the board. What can we gather from the results?

Open Ended

What can you conclude from the results shown on the board?

​Conclusion

What can we conclude from our results?

(Discussion)

Multiple Choice

What is a hypothesis?

• A hypothesis is a proven fact in science.
• A hypothesis is a random guess with no basis.
• A hypothesis is a conclusion drawn without any evidence.
• A hypothesis is a proposed explanation for a phenomenon or a scientific question that can be tested through experimentation or observation.

Multiple Choice

In this experiment what was the stimulus?

• Chemical Change

• Light colour change

• Pressure change

• Temperature change

Multiple Choice

What was the response?

• Blinking

• Breathing

• Clicking the mouse

• Nothing

Key Points

Remember your body systems document? open it up!

Record the following key points!

A stimulus is a change or signal in the organisms environment, that an organism can react to.
A response is how we react to the stimulus.

The following cells react to these specific stimuli
uOlfactory cells - Reacts to smells

uHair cells - Reacts to vibrations

uTaste receptors - Reacts to chemicals

uPhotoreceptors - Reacts to light

uThermoreceptors - Reacts to temperature

uMechanoreceptors - Reacts to Pressure

Open Ended

Lesson Reflection:
A) What did you like about the lesson?
B) Did you need help throughout the lesson
C) Did you understand the concepts?
D) Did you help anyone?