Nervous system Special senses. Flashcards
4 organs and functions that make up the special senses?
- Eye – sight
- Ear - hearing and balance
- The taste buds – taste
- Olfactory receptors in nose – smell
6 accessory organs to the eye
- Eyelids
- Eyelashes
- Tarsal glands
- Conjunctiva
- Lacrimal apparatus
- Extrinsic eye muscles
How do the feeding habits of an individual relate to eye placement on the head?
Predators have binocular vision for depth perception.
Prey have monocular vision for a wider range of view (safety, survival.)
What are the two types of vision?
Monocular and binocular.
What does the iris do?
Controls the constriction and dilation of the pupil.
What does the ciliary body do?
It is the muscle that controls the shape of the lense.
What is the retina?
it is the layer that contains the rods and cones.
What is the vitreous humor?
The fluid that covers the posterior layer of the inner eye.
What is tapetum lucidum?
It allows the animal to see more clearly in dim light.
What is aqueous humor?
watery fluid in the front of the eye.
What is the sclera?
Tough outer layer of the eye.
Difference between rods and cones
Rods are sensitive to light, cones are sensitive to colour.
What are the functions of the ear?
Balance, hearing.
The 3 external parts of the ear?
Pinna, external auditory canal, tympanic membrane.
The three parts of the middle ear?
Ossicles, eustachian tube, tympanic bulla.
What are the three parts of the inner ear?
Semicircular canals, vestibule, and cochlea.
The function of the pinna
Channel sound into the ear.
The function of the external auditory canal (2)
Channels sound to the tympanic membrane, wax production.
What are the glands that produce wax in the external auditory canal?
Sebaceous glands.
What are the functions of the tympanic membrane (2)
To separate the outer and middle ear, vibrating sound.
What is the function of the ossicles?
To transmit sound from the outer ear into the inner ear.
What are the three ossicles in order?
the malleus, incus, and stapes in the ear.
What is the function of the eustachian tube?
To relieve pressure when barking or swallowing.
What is the function of the tympanic bulla?
Separates middle and inner ear.
What are the functions of the semicircular canals?
The three semicircular canals are on different planes so we maintain balance and orientation while moving etc.
What is the name of the fluid in the semicircular canals, how does it help our brain to sense movement?
Endolymph, by washing over sensory cilia as we move.
What are the vestibules? What do they contain (2)?
Two sac-like spaces responsible for processing head position, filled with endolymph fluid and lined with sensory epithelium (macula).
What does the cochlea contain?
The organ of Corti - the hearing organ.
