Bio 1711- Special senses II

Stimulus

Perception of event

Sensation

Initial physical and neral reception

Receptors

Structures that respond to stimuli and initial sensory input to CNS

Somatic sensory receptors 

Skeletal muscles

Visceral sensory receptors

Smooth muscle

Special sensory receptors

Located in the head (complex sense organs)

Exteroreceptors

External environment

Interoreceptors

Internal organs

Chemoreceptors

Chemical environment

Thermoreceptors

Temperature changes

Mechanoreceptors

Physical stimuli

Baroreceptors

Pressure changes

Nociceptors

Very painful stimuli

Refered pain

Pain is felt on skin in another part of body due to visceral sensory neurons sharing a tracts in spinal cord

Olfaction

Sense of smell

Olfactory gland

Clears out odourants

Cibriform place

Bony plate part of olfaction

Basel cells

Replace support cells

Support cells

Columnar epithileum

Mucous

Sticky odourant adhesion

Olfactory receptor cell

Picks of chemical smell

Frontal lobe (olfactory cortex)

Interprete smell

Limbic system (olfactory cortex)

Emotional response to smell

Gustation

Taste (requires dissolved substances)

Papillae

Bumps on tongue

Vallate

Foliate

Fungiform

Filiform

Part of the tongue that has no taste buds

Sweet

organic compounds

Salty

Metal ions

Sour

Acids

Bitter

Alkaloids

Umami

Meaty flavour

Lacrimal gland

Secretes tears

Tears flow across eyeball with

Gravity, and blinking

Lacrimal punctum

Tear exit eyeball

Lacrimal sac

Tears drain into

Nasolacrimal

Tears get dumped into nasal cavity

Conjunctiva

Thin membrane lining eye and inner eyelids

Layer 1 of eye

Fibrous tunic

Layer 2 of eye

Vascular tunic

Layer 3 of eye

Nervous tunic

Cornea

Reduces refraction to focus light

Sclera

Gives the eye its shape

Choroid

Provides nutients and absorbs light in eye

Ciliary body

Ciliary process & Ciliary muscles

Ciliary processes

Secretes aqueous humour fluid

Ciliary muscles

Smooth muscles that alters lens shape

Sensory ligament

Connects ciliary muscles and lens

Iris

Regulates light coming into eye

Sphincter pupillae

Closes pupils

Dilater pupillae

Dilates pupils

Lens

Focuses light on retina

Flattened lens

Looking far

Rounded lens

Looking close

Nearsightedness (myopia)

Eyeball is slightly longer that normal

Farsightedness (hyperopia)

Eyeball is slightly shorter than normal

Astigmatism

Cornea is uneven

Retina

Vision receptor

Optic disc

Blind spot

Macula lutea

Best vision (straight on)

Peripheral retina

Best low light vision

Pigmented layer

Retinal layer that absorbs access light

Neural layer

Retinal layer of 3 layers

Rods

Shapes and movement

Cones

Sharp, color vision 

Anterior cavity

Filled with aqueous humorous

Posterior cavity

Filled with vitreous humour

Scleral venous sinus

Drains fluid from eye

Brain pathways of vision

Eyeball nerves from both eyes go to both sides of brain