5.1 Stimuli and responses 1HVTTO

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 1

5.1 Stimuli and responses

• Jacket in your locker
• Put your things on your desk

       Laptop/Book

       Notebook, pencil case

• Bag on the floor
  
• Read pages 118-119

Lessongoals

• Understand: I can explain the difference between a stimulus and a response by correctly describing both terms.
• Apply: I can give examples of stimuli and responses by identifying real-life situations where they occur.
• Analyze: I can predict responses for different types of stimuli by reasoning how the body would react in various scenarios.

Homework 5.1

Asgmt 1-3

Scan the chapter

Use your book and laptop/notebook

• Go to chapter 5.1 on pages 118-119
• Quickly scan the text for difficult/unknown words
• Make a list of all the words you don't know/understand, add these to your PIF
• Add descriptions and/or synonyms of these words during the lesson

In what ways can we sense the world?

Think-Pair-Share

• Think: Work on the assignment on your own.
• Write in your notebook: How does being able to sense the world help animals survive?
• Use sentences like:
• Without sight a(n) ... would not be able to ....
• Smell is necessary because it helps .....

• Pair: Discuss and compare with your neighbour, improve your answer
• Share: Talk about given answers during plenary session.

Stimulus (plural: stimuli)

• Something that produces a reaction in an organism
• Influences from the environment
• 'Things' sensory organs react to

Stimuli

Stimuli and impulses

• Sensory organs contain sensory receptors 
• Sensory receptors take in stimuli
• Stimuli become impulses in sensory receptors
• Impulse = electric signal in neurons 
• Impulses travel to the brain

The nervous system (see 1.1 page 11) contains all your nerves. 

These transport impulses from sensory organs to the brain

Specialized cells that can react to certain stimuli

Your nerves are made up of many cells, these cells are called neurons

You're on the sidewalk and notice this. What are the most important stimuli?

Impulses and responses

Sensory receptors --impulse--> brain

Once the impulses reach your brain, you become aware

Brain --impulse--> effectors

You can move and react to the stimuli = Response

Effectors are organs that can act (= do something), they act when instructed by impulses.

Often these are muscles, but they can also be glands that start producing substances

impulse

impulse

0

Responses

Responses can be:

• Voluntary > (conscious) decisions
• Involuntary > automatic, without your will

Light is the stimulus your eyes react to

Sound is the stimulus your eyes react to

Chemicals in food/tastes are the stimuli your tongue reacts to

Chemicals in the air/scents are the stimuli your nose reacts to

Heat is a stimulus your skin reacts to

Cold is a stimulus your skin reacts to

Pressure (something pushing against you) is a stimulus your skin reacts to

Pain is a stimulus your skin reacts to

Texture (slippery, hard, soft, rough, etc.) is a stimulus your skin reacts to

Sensory receptors in your eyes change light stimuli into impulses, these are sent to the brain

Sensory receptors in your ear change sound stimuli into impulses, these are sent to the brain

Sensory receptors in your tongue change taste stimuli into impulses, these are sent to the brain

Sensory receptors in your nose change scent stimuli into impulses, these are sent to the brain

Sensory receptors in your skin change heat, cold, pain, pressure and texture stimuli into impulses, these are sent to the brain

The brain processes the impulses of all sensory organs.

The moment this happens you become aware of the stimulus.

After this you can react.

To do this, the brain sends impulses to effectors.

Glands (organs that produce a substance) are a type of effector

An example of a respons is: 

You smell tasty food > saliva glands in your mouth start producing saliva

Muscles are a type of effector.

An example of a respons is:

You see a ball coming towards you > muscles in the arm and hand make you catch the ball

The brain sends impulses to effector as a respons to stimuli

The brain sends impulses to effector as a respons to stimuli

Perceiving

Responding

1. What stimuli will your body experience in the situation described underneath?
2. What will your response be?
3. Is it voluntary or involuntary?

You are using the stove, the pan has been on the stove for about 10 minutes.
You touch the hot metal handle of the pan.

These words I'll add to my PIF

What you should do: 5.1

• Read pages 118-119 TB
  
• Asgmt 1-3 pgs 120-121 WB

Done with the above?

• Work on the next chapter(s)
• Learn for the test 
• Make other homework
• Read a book

Zs = Working in Silence

• No asking questions
• Silent, don't disturb anyone
  
• Stay at your  desk

What you should do: 5.1

• Read pages 118-119 TB
• Asgmt 1-3 pgs 120-121 WB

Done with the above?

• Work on the next chapter(s)
• Learn for the test 
• Make other homework
• Read a book

Zw = Working with whispering

• Teacher is available for questions
• Only whisper with the student next to you
• Stay at your  desk

Is the beating of your heart an example of an involuntary response?
Why (not)?

Tidy Duty

3 people each lesson

• Desks: empty and straight
• Chairs:  underneath the desks OR end of day: on the desks
• Floor: no rubbish