Sensory System www.juniorscience.ie
Sense Sense Organ Sight EYE Sound EAR Touch SKIN Smell NOSE Taste TONGUE www.juniorscience.ie
front view of the eye click for labels “white” pupil iris www.juniorscience.ie
Inside of the eye Ciliary muscle retina optic nerve cornea pupil iris lens www.juniorscience.ie
The function of the cornea light rays the cornea allows light to enter the eye, and refracts (bends) the rays www.juniorscience.ie
the pupil is a hole into the eye that allows light to get in Why is the pupil black? The colour of the pupil looks black because it is not reflecting any light out of the eye www.juniorscience.ie
the iris gets bigger or smaller to control the size of the pupil www.juniorscience.ie
A B C D E F G can you remember what’s what? CORNEA RETINA PUPIL CLICK FOR ANSWERS RETINA PUPIL OPTIC NERVE IRIS LENS CILIARY MUSCLE www.juniorscience.ie
the lens focuses light rays to form a clear image on the retina www.juniorscience.ie
side view lens ciliary muscle l e n s front view The ciliary muscle contracts and relaxes to change the shape of the lens www.juniorscience.ie
the optic nerve brings a message to the brain about what we see www.juniorscience.ie
retina cornea optic nerve pupil iris lens click for answers OB30 locate the main parts of the eye on a model or diagram and describe the function of the cornea, iris, lens, pupil, retina, optic nerve and ciliary muscle Choose a name from the list above to match the functions in the table 1. contains sensory cells which detect images 2. contracts and relaxes to change the shape of the lens 3. allows light into the eye and refracts (bends) the rays 4. brings messages to brain about what we are seeing 5. allows light into the inside of the eye 6. contracts and relaxes to change the size of the pupil 7. focuses a clear image on the retina retina ciliary muscle cornea optic nerve pupil iris lens click for answers www.juniorscience.ie
Look at the diagram and explain what is happening www.juniorscience.ie
This CNS has been preserved for display in a Science museum the role of the CENTRAL NERVOUS SYSTEM (CNS) is to control all the actions of the body www.juniorscience.ie
…the CNS is made up of the brain and spinal cord… the brain takes up most of the space inside the skull the spinal cord is found inside the backbone www.juniorscience.ie
…nerve cells are very long narrow cells… …nerve cells carry information between the CNS and every area of the body… …nerve cells are very long narrow cells… …the are two types of nerves cells: SENSORY nerves bring messages from the sense organs to the CNS MOTOR nerves bring messages from the CNS to the muscles of the body www.juniorscience.ie
…the sensory function of nerves is to gather information and take it to the CNS… sight sound smell touch taste www.juniorscience.ie
“round of applause please” …the motor function of nerves is to take messages from the CNS to the muscles… “round of applause please” www.juniorscience.ie
can you describe what is happening in this picture? OB29 describe the role of the central nervous system and the sensory and motor functions of nerves can you describe what is happening in this picture? www.juniorscience.ie