A&P test 6

Muscle spindles

Cause muscles to contract in stretch reflex

Golgi tendon organs

Cause muscles to relax in tendon reflex

Proprioceptors

detect position of body

ex: Joint and muscle positions

What receptors detect sound waves?

Hair cells

What receptors detect pain?

Nociceptors

What receptors would detect carbon dioxide in the blood?

Chemoreceptors

In sensory pathways, where are third order neurons located?

Thalamus

What is olfaction

The sense of smell, receptors located in olfactory epithelium

Olfaction- steps of transduction

1. Odorant binds to olfactory receptor in nasal cavity

2. G- protein is activated inside receptor cell

3. adenylate cyclase is activated

4. ATP converted into cyclic AMP

5. Cyclic AMP opens ion channels = depolarization

3 steps of taste perception

1. From cranial nerves, messages sent to medulla oblongata

2. Neurons synapse with other neurons in the thalamus

3. Information is sent to the gustatory cortex

What do activated photoreceptors synapse with?

Bipolar cells, which then relay to ganglion cells

What happens in the dark (physiology of vision)

Photoreceptors DEPOLORIZE and release glutamate onto bipolar cells, inhibiting them.

What happens in the light (Physiology of vision)

The photoreceptors HYPERPOLORIZE and stop releasing glutamate onto bipolar cells, which stimulates ganglion cells

What part of brainstem receives visual information, and is the region for the visual reflex?

Midbrain

What are the receptors for hearing called, and where are they located?

Hair cells- located in spiral organs of the cochlea

What happens when hair cells are distorted or bent?

Depolarize

-causes K+ and Ca+ to enter cell

What happens after a photon strikes the disc of the outer segment of a photoreceptor?

Opsin is activated, activating transduction

What does the breakdown of cyclic GMP cause? (transduction for vision)

Inactivated sodium channels, stopping the dark current

Equilibrium is detected by hair cells located in the..

Vestibular complex

Which nervous system division has short preganglionic fibers and long postganglionic fibers?

sympathetic

What neurotransmitter binds to cholinergic receptors?

Acetylcholine

What are the 2 types of cholinergic receptors?

Nicotinic and muscarinic

When norepinephrine binds to alpha 1 receptors on the smooth muscle of the iris, the pupil…

dilates

Alpha 2 receptors are mostly for modulation of a synapse and are found on what type of neuron

Preganglionic neurons

what happens to the heart rate if epinephrine binds to beta 1 adrenergic receptors on cardiac muscle

Increases

If epinephrine binds to beta 2 adrenergic receptors on smooth muscle of bronchioles, the bronchioles will

Dilate

What receptor detects stretch and movement, and is located in ligaments, dermis, and hypodermis?

Ruffini endings

What information is relayed through the posterior column pathway, or medial lemniscsal pathway?

Discriminative touch

In sensory pathways, where are third order neurons located?

Thalamus

Sensory transduction

Conversion of a stimulus into electrical signals for brain processing

Ruffini endings

detect skin stretch, slow adapting

What receptor detects odorants and tastants

Chemoreceptors

What receptor detects sound waves

Mechanoreceptors

Somatosensory cortex

Parietal lobe

Touch, pain, proprioception

Effect of blood vessels when norepinephrine binds to alpha-1 adrenergic receptor

Vasoconstriction = increase blood pressure

Effect of norepinephrine binding to alpha-2 adrenergic receptor

Inhibits neurotransmitter release- lowers BP

Effect of norepinephrine binding to beta-1 adrenergic receptor

increases heart rate

Effect of norepinephrine binding to beta-2 adrenergic receptor

Bronchodilation- eases breathing

What neurotransmitters are part of sympathetic communication

Acetylcholine and Norepinephrine

Preganglionic neurons

Begin in CNS,

Signals from CNS to autonomic ganglia

Postganglionic neurons

Outside CNS (autonomic ganglion)

Epinephrine

Adrenaline

Norepinephrine

Fight or flight response

Referred pain

Pain felt in location different from site of injury

Dermatomes

Specific nerve roots innervate different portions of skin

What are the adrenergic receptors?

Alpha-1

Alpha-2

Beta-1

Beta-2

Special senses

Smell

Taste

Vision

Hearing/equilibrium

5 types of tatse

Sweet

Sour

Bitter

Salty

Umami

Fluid in anterior cavity of eye

Aqueous humor

Fluid in posterior cavity of eye

Virtreous humor

Merkel cells

Slow adapting

light touch and texture

basal layer epidermis

Tactile corpuscles

light touch and low freq vibrations

fast-adapting

Lamellated corpuscle

Fast-adapting

deep in dermis

deep pressure high freq vibrations

Transduction

Physical stimulus converting into electrical signal

Transmission

Signal travels to brain stem or spinal cord

Perception

final step of stimulus

Reception

Sensory organs detect a stimuli

Processing

brain organizes and interprets info