The Senses Flashcards
5 senses
- touch
- smell
- taste
- sight
- hearing
The skin
Organ of touch and temperature
The tongue
Organ of taste
Taste buds detect
- sweet
- salt
- sour
- bitter
The nose (2)
- Organ of smell
- Olfactory neurons in the nose detect smells
The eye
Organ of sight
Main parts of the eye (diagram) (13)
- Conjunctiva
- Sclera
- Cornea
- Choroid
- Retina
- Fovea
- Blind spot
- Optic nerve
- Lens
- Iris
- Pupil
- Ciliary muscles
- Aqueous and vitreous humours
Function of the conjunctiva
Thin transparent lining protecting the cornea.
Function of the sclera
Tough fibrous outer layer – the ‘white’ of the eye;
it maintains the shape of the eyeball
Function of the cornea
Allows light into the eye and bends it to help focus it on the retina
Function of the choroid
Contains blood vessels supplying food and oxygen to the cells of the eye
Prevents reflection
Function of the retina
Contains
- light receptors
- rods (for black and white vision in dim light)
- and cones (for colour vision in bright light)
Function of the fovea
Part of the retina where most images are focused
The fovea is where our best vision is [mainly cones]
Function of the blind spot
Where the optic nerve fibres pass through the retina and there is no room for receptors.
Function of the optic nerve
Carries impulses to the brain
Function of the lens
Focuses light on the retina
Function of the iris
Contains blood vessels and melanin [giving us our eye colour]
Controls the amount of light entering the eye [through the pupil].
Function of the pupil
Black circle at the front of the eye
Lets light into the eye
Function of the ciliary muscle
Thickened edge of the choroid that controls the shape of the lens (accommodation) to focus the image on the retina
The ear
Organ of hearing
Parts of the ear (diagram) (
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Function of the pinna
Collects vibrations
Channels them into the auditory canal
Function of the auditory canal
Carries vibrations to the eardrum
It has hairs and wax glands to trap dirt and germs.
Function of the eardrum
Membrane of skin that vibrates when sound waves hit it.
Carries the vibrations to the middle ear
Function of the ossicles
The hammer, anvil and stirrup
Amplifies the vibrations and passes them on to the oval window
Function of the Eustachian tube
Not part of the ear
Connects the middle ear with the pharynx
Equalises pressure on each side of the eardrum
It opens when we swallow, cough
Function of the cochlea
Responsible for hearing
Contains nerves that convert sound vibrations into electrical impulses that are sent to the brain along the auditory nerve
Organ of Corti
In the cochlea
Contains receptor cells that allow hearing
Balance
Detected by the vestibular nerve
The semi-circular canals
Glue ear
Hearing disorder
Cause by too much sticky fluid in the middle ear
Corrected by decongestants
A receptor
A cell that can detect a stimulus
A stimulus
Any change in your environment
Function of the suspensory ligaments
Hold the lens in place
Accomodation
The ability of the lens to change its shape (focal length) to form a clear image.
Close vision
Ciliary muscle contracts, the suspensory ligaments relax, the lens becomes thicker.
Distant vision
Ciliary muscle relaxes, the suspensory ligaments tense, the lens becomes thinner.
Function of the aqueous humour
Watery liquid that supplies the lens and cornea with nutrients
Helps keep the shape of the cornea and lens.
Function of the vitreous humour
Gel that helps maintain the shape of the eye.
Correction of long sighted
Convex lenses
Correction of short sighted
Concave lenses
The inner ear
Contains a coiled, fluid-filled tube called the cochlea and the semi-circular canals.
Function of the semi-circular canals
Help us keep our balance and posture
