Receptors

Define Gustation

Our sense of taste that permits us to perceive the characteristics of what we eat and drink. Often referred to as contact chemoreception because we must come in contact with a substance to experience its flavor.

Define Proproceptors

Proproceptors • Located in muscles, tendons, and joints. • Detects body and limb movements, skeletal muscle contraction and stretch, and changes in joint capsule structure. Thus, even if you are not looking at your body joints, you are aware of their positioning and the state of contraction of your skeletal muscles, because proprioceptors send information to the CNS.

Define Olfaction

The sense of smell. Smell is often referred to as remote chemoreception

what stimulate photoreceptors?

located in eye, detect changes in light intensity, color, and movement

define thermoreceptor and what stimulate them?

respond to changes in temperature.

Define Sensation

Conscious awareness of incoming sensory information

Describe the receptor modality

Contains receptors for airborne molecules

Define Vision

Photoreceptors: detect light, color, & movement. accessory structures :protect against foreign objects keeps eye surface clean and moist

what stimulate mechanoreceptors?

- repond to touch, pressure, vibration, stretch. Most cutaneous receptors are mechanoreceptors because they respond to pressure and touch on skin. Located in in ear for equilibrium and hearing.

Starting with the a sound wave, follow the path of sensory information from the auricle to the brain. (**only as detailed as in class) Should include terms: Aurical, EAM, Tympanic Membrane, Ear Ossicles, Oval Window, Spiral Organ, Hair Cells, Tectorial Membrane

Bending of stereocilia -->cochlear nerve-->vestibulocochlear nerve (CN VIII)-->Thalmus-->Primary auditory cortex

What are the 6 modalities of receptors?

Chemo-receptors, thermoreceptors, photoreceptors, mechanoreceptors, barareceptors, nociceptors.

What is the name of their free dendritic ending?

Free nerve endings are called olfactory hairs.

Define exterocepters

Exterocepters • Detect stimuli from external environment. EX. Receptors in your skin because external stimuli typically cause sensations to the skin. • Receptors in special senses considered exteroceptors because they usually interpret external stimuli, such as taste of food you just ate or sound of music on radio. • Found in mucous membranes that open outside of the body, such as nasal cavity, oral cavity, vagina, anal canal.

What are the 3 classes of General Receptors

Exterocepters, Interoceptors, Proproceptors

Describe the location and function of gustatory cells

Gustatory cells • Are taste receptors housed in specialized sensory organs termed taste buds on the tongue surface.

Describe the location and function of Hair cells for equilibirum

Hair cells are sensory receptors of the inner ear for both equilibrium and hearing. Located in the macula

Define Interoceptors

Interoceptors • Also called visceroceptors • Detect stimuli in internal organs. • Primarily stretch receptors in smooth muscle of organs. • Most of time we are unaware of these receptors, but when smooth muscle stretches to a certain point (e.g. eating a large meal stretches our stomach wall), we may become aware of these sensations. • Report on pressure, chemical changes in visceral tissue, and temperature.

Describe the location and function of Photoreceptor cells

Located in the inner layer and contains rods and cones that This layer of the retina is responsible for receiving light rays and converting them into nerve impulses that are transmitted to the brain.

Hearing: Describe the location and function of Hair cells

Located in the spiral organ and functions by converting sound waves to nerve impulses.

Pathway of sensory information from nasal retina to the brain

Photoreceptors --> bipolar cells-->ganglion cells--> form the optic nerve-->optic chiasm (decussate)-->optic tract -->(superior colliculi) --> thalamus--> primary visual cortex of occipital lobe for interpretation

Describe where rods and cones are concentrated and the stimuli for each

Rods are primarily located in the peripheral regions of the neural layer. Rods are especially important when the light is dim. rods pick up contrasting dark and light tones, but cannot distinguish color. Cones are activated by high-intensity light and provide precise visual acuity and color recognition. Thus, when you notice the fine details in a colorful picture, the cones of your neural layer are responsible. Cones are concentrated at the posterior part of the neural layer at the visual axis of the eye.

Starting with the a head tilt, follow the path of sensory information from the hair cell to the brain. (**only as detailed as in class). Should include terms: vestibule (saccule, utricle) Macula, ampullae, sterocilia & kinocilium, otolithic membrane, crista ampullaris, cupula, endolymph

Stereocilia and kinocilia embed into cupula (otolithic membrane) head rotatesendolymph moves cupula bends the stereocilia. Hair cells Vestibular branch of CN (VIII) medulla oblongata balance

What is the name of their microvili and cilia that detect movement?

Stereocillia and kinocillium

Define Stimuli

Stimuli - changes in external or internal environment

Define Receptor

Strcutures that detect stimuli

what stimulate baroreceptors?

detect changes in pressure within body structures. These sensory receptors branch repeatedly within connective tissues vessel or organ walls, especially elastic layers. Any pressure stimulus that cause wall deformation result in change in nerve impulse rates from receptors and pressure sensation.

Explain chemoreceptor and what may stimulate them

detect chemicals such as specific molecules dissolved in fluid in external and internal environments, including ingested food and drink, body fluids, and inhaled air. EX. Receptors in taste buds on tongue are chemoreceptors because they respond to specific molecules in ingested food. Likewise, chemoreceptors in some of our blood vessels monitor the concentration of oxygen and carbon dioxide molecules in our blood.

What is the name of their free dendritic ending?

gustatory microvillus: taste hair. Sweet, *bitter, salty, umami, *sour

What stimulate nociceptors?

respond to pain caused by either external or internal stimuli. Somaticnociceptors detect chemical, ehat, or mechanical damage to the body surface or skeletal muscles. • Ex. Exposure to acid, touching a hot pan, suffering a sprained ankle stimulate somatic nociceptors. Visceralnociceptors detect internal body damage within viscera due t excessive stretching of smooth muscle, oxygen deprivation of tissue, or chemicals released from damaged tissue.

What is the name of their microvili and cilia that detect movement?

sterocillia and tectoral membrane

Describe the location and function of Olfactory receptor cells

• Apical end : free nerve endings (olfactory hairs) that project through the mucous • Contain receptors for airborne molecules.

Where is the location and what is the stimuli of lamellated corpuscles is?

• Large receptors that detect deep pressure and high frequency vibration. • Center of the receptor houses several dendritic endings of sensory neurons wrapped within numerous concentric layers of flat, fibroblast-like cells. This structure ensure that only deep-pressure stimuli will activate the receptor. • Lamellated corpuscles are found deep within rectucular layer of the dermis; in the subcutaneous layer of the palms of hands, soles of feet, breasts, and external genitalia; in the synovial membranes of the joints; and the walls of some organs.

Where is the location and what is the stimuli of a tactile corpuscles is

• Previously called meissner corpuscles, physically different from tactile discs. • Large, encapsulated oval receptors. • Formed from highly intertwined dendrites enclosed by modified neurolemmocytes, which are then covered with dense irregular connective tissue. • Are phasic receptors for light touch, shapes, and texture. • Housed within the dermal papillae of skin, especially in the lips, palms, eyelids, nipples, and genitals.

Where is the location and what is the stimuli of root hair plexuses is

• Specialized free nerve endings that form web like sheath around hair follicles in reticular layer of dermis. • Any movement or displacement of hair changes arrangement of branching dendrites, initiating nerve impulse. • These receptors quickly adapt; thus; although we feel initial contact of long sleeved shirt on our arm hairs when we put on the garment, our conscious awareness subsides immediately until we move and the root hair plexuses are restimulated.