Chapter 14
Polysynaptic Reflex
One or more interneurons connect afferent (sensory) and efferent (motor) signals
Sensation
The process of sensing our environment through touch, taste, sight, sound, and smell
Contralateral Reflex
The reflex occurs on the opposite side of the body from the stimulus
The function of the round window is to dampen sounds after they stimulate the hair cells.
True
Where is the olfactory epithelium located?
in the roof of the nasal cavity
If its receptor and effector are on the same side of the body, a reflex arc is termed ____________; if on opposite sides, it is ____________.
ipsilateral; contralateral
Which of the following is NOT one of the basic taste sensations?
metallic
Which class of receptors can respond to extreme stimulating agents otherwise detected by all the other classes?
nociceptors
Iris
Two smooth muscles (radial & circular), pigment gives color, controls pupil size
Choroid Coat
Underneath sclera, blood vessels, brown pigment absorbs excess light
Monosynaptic Reflex
When a reflex arc consists of only two neurons in an animal (one sensory neuron, and one motor neuron)
Cornea
outermost transparent cover of the eye, no blood vessels, transplants work very well
A structure that detects stimuli is known specifically as a
receptor
Stretch Reflex
A muscle contraction in response to stretching within the muscle. It is a monosynaptic reflex which provides automatic regulation of skeletal muscle length
Ipsilateral Reflex
A reflex in which the response occurs on the side of the body that is stimulated
Types of Taste
1. Umami 2. Sweet 3. Sour 4. Salty 5. Bitter
Extrinsic muscles
6 outer eyeball muscles
Withdrawl Reflex
A spinal reflex intended to protect the body from damaging stimuli. It is a polysynaptic reflex, causing stimulation of sensory, association, and motor neurons
Crossed-Extensor Reflex
A withdrawal reflex. When the reflex occurs the flexors in the withdrawing limb contract and the extensors relax, while in the other limb, the opposite occurs
Retina
Back wall of eyeball, contains photoreceptor cell
Receptor
Classified by Development (innate or acquired), Response (somatic or autonomic), Complexity of circuit (monosynaptic or polysynaptic), and processing site (Spinal or cranial reflex)
Conjunctiva
Clear membrane that lines eye surface except for cornea
Lens
Focuses light onto retina
Eye Lid
For protection
Pupil
Hole that is constricted to regulate the amount of light that enters the eye
Macula lutea
Lateral to optic disc, in center is fovea centralis
Rods
Long, thin, dim-light and peripheral vision photoreceptor
Lysozyme
Lubrication
Optic Disc
No vision (blind spot), optic nerve entrance, no photoreceptors
Optic Nerve
Sends sensory input to occipital lobe
Cones
Short, blunt, high acuity color vision photoreceptor
Association of Smell with Taste
Smell and taste are both chemical receptors, smell enhances the perception of taste
Ciliary Body
Smooth muscle fibers that change lens shape; attached with suspensory ligaments to hold lens
Lacrimal Gland
Tear secretion, protection
Vitreous Humor
The transparent jellylike tissue filling the eyeball behind the lens
Perception
The way we interpret sensations and therefore make sense of everything around us
Meissener's corpuscles, Merkel discs, Pacinian corpuscles, and free nerve endings are all examples of skin receptors.
True
Sclera
White of the eye, tough tendon-like tissue, protects and gives shape
Aqueous Humor
fluid in the eye, found between the cornea and the lens
What types of photoreceptor cells are found in the retina?
rods and cones
Fovea Centralis
sharpest vision, no rods
A familiar type of monosynaptic reflex that monitors and regulates the length of skeletal muscle is the
stretch reflex
