The Sense Organs: Structure and Function of the Eye and Skin | IGCSE Biology

This detailed presentation covers the structure and function of the sense organs, focusing on the eye and skin as part of the Cambridge IGCSE Biology syllabus. Learn about the anatomy of the eye, how vision works, adaptations for focusing, and common eye defects. Explore the role of the skin in temperature regulation, protection, and sensory reception. Perfect for students preparing for exams!

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Sense Organs
Sense organs are group of receptor cells responding to
specific stimuli: light, sound, touch, temperature and
chemicals. A stimulus is a change of environment that affects
an organism. All sense organs have:
•Receptor cells
•Blood supply to help provide substances for producing
energy
•Tissues that help in making the most out of the stimulus

3. The Eye(Vision)
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The Eye

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The Eye

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The Eye
Rods:
•sensitive to dim light
•found all around the retina (other than the blind spot)
Cones:
•sensitive to bright light
•3 types of cones which are sensitive to different colours of light (RGB)
•maximum concentration is at fovea
Note: the lens becomes less elastic and loses its ability to change shape at old
age. One cannot see close by objects easily. Smokers may experience this
problem earlier than non-smokers as the smoke ages the molecules in the
lens.

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The Eye

13. TEMPERATURE
REGULATION
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