Loading the lesson
Loading the lesson
Search AllRounder.ai
Search the courses, subjects, tracks, games and features, or jump straight to a page.
Search the courses, subjects, tracks, games and features, or jump straight to a page.
Learn it your way
A short class with Sarah and her students. The other ways are under More.
Sign up free to listen. Transcripts are free to read.
Today, we're going to learn about how our eyes adjust to different light levels. Can anyone tell me what happens to our pupils when we walk from a bright room into a dark one?
I think they get bigger to let more light in.
Exactly, well done! The pupil enlarges to allow more light to enter so we can see in dim conditions. Now, what do you think happens in bright light?
I think they get smaller!
Correct! The iris controls the pupil size, constricting it to protect the retina from too much light. Let's observe this in our activity.
Now, let's perform Activity 13.8! Look into your partner's eye and shine a light on it. What do you observe?
The pupil got really small when I turned the torch on!
And when I switched it off, it got bigger!
Good observations! This contraction and dilation of the pupil is our body's way of adapting to light. Why do you think it's important?
To see better and protect our eyes!
Great job, everyone! Let's group our experiences. What happens to the pupils in bright light versus dim light?
They shrink when it's bright and enlarge when it's dark!
Exactly! This response is critical for adapting to surroundings. What role does the iris play in this?
The iris controls how much light comes in by changing the size of the pupil.
Correct! It's like a camera adjusting its aperture. Remember this concept; it helps us understand how our eyes function.
In the light so bright, pupil's tight; in the dark, it’s wide, so you can see inside.
Once upon a time in a land of bright light, the wise iris decided to shrink the pupil to protect the eye's sight. But when night fell, the pupils grew wide, allowing all the dim light to be welcomed inside.
Pupil's Play: 'Bright light makes it tight; dark night makes it bright!'
P.E.A.R. - Pupil Enlarges As Room darkens.
Term
What controls the pupil size?
Click to flip
Term
What happens to pupils in dim light?
Click to flip
This section focuses on the reaction of the human pupil to changing light intensities, highlighting the importance of pupil size in regulating light entry into the eye.
In this section, students explore how the pupil of the eye reacts to light. Through an interactive activity, they observe changes in pupil size when exposed to bright and dim light. This observation helps to understand the role of the iris and pupil in controlling light entry into the eye.
In Activity 13.8, students are tasked with observing their friend's pupil size under varying light conditions using a torch. The pupil enlarges in dim light and constricts in bright light, indicating the iris's role in regulating light entry. The discussion emphasizes how our eyes adapt to different lighting environments, allowing us to see clearly in various situations. Understanding this mechanism is critical for appreciating the eye's functionality and the control of light exposure.