Irritability Flashcards
Define stimulus
A change in the environment that an organism responds to
Define response
A change in the organism brought about by the stimulus
Define receptor
A specialized cell that receives stimuli
Define effector
The part of the organism that responds to the stimulus
Define irritability
The ability to detect and respond to stimuli
What is irritability necessary for?
- mating
- Finding food
- Moving away from hot to cold temperatures
- Protecting the body from damage
- Survival
Function of the conjunctiva
Protects the cornea
Function of the cornea
Refracts light rays onto the retina
Function of pupil
Allows light to enter the eyeball
Function of the iris
Controls the amount of light entering the eye
Function of sclera
Protects the eyeball
Function of optical nerve
Carries impulses from the retina to the brain
Explain short sightedness
They can see near objects, but not far objects
Light rays from near objects focus on the retina; light rays from distant objects focus in front of the retina
How is short-sightedness corrected
By wearing concave lenses as spectacles or constant lenses
Explain short-sightedness
Light rays from near objects focus on the retina
Light rays from distant objects focus in front of the retina.
How is short-sightedness corrected
By wearing concave lenses as spectacles
Explain long-sightedness
Light rays from near objects focus behind the retina. Light rays from distant objects focus on the retina
How is long-sightedness corrected
By wearing convex lenses as spectacles
How is glaucoma treated
With eye drops or laser treatment
