general

Question 1

K+ levels and Ek

Answer 1

intracellular: 155mM
extracellular: 4mM
Ek: -98mV

Question 2

Na+ levels and Ena

Answer 2

intracellular: 12mM
extracellular: 145mM
Ena: 67mV

Question 3

Cl- levels and Ecl

Answer 3

intracellular: 4.2mM
extracellular: 123mM
Ecl: -90mV

Question 4

Ca2+ levels and Eca

Answer 4

intracellular: 0.0001mM
extracellular: 1.5mM
Eca: 110mV

Question 5

Meissner’s corpuscles

Answer 5

comprised of looping axonal terminals and intertwining support cells
low frequency vibrations

Question 6

Merkel’s discs

Answer 6

dome structure of axon terminals and Merkel cells
particularly abundant in fingertips, lips and genitalia
they are the reason people can read brail

Question 7

Pacinian corpuscles

Answer 7

sensory axon surrounded by fluid filled capsule (onion-shaped appearance)
high frequency vibrations
capsule acts as a filter and only allows transient disturbances at high frequency to activate the nerve endings

Question 8

Ruffini’s corpuscles

Answer 8

nerve terminals intertwined with collagen fibrils

pressure activated

Question 9

free nerve endings

Answer 9

penetrate into epithelial cells

noxious

Question 10

circumvallate papillae

Answer 10

largest
contain many thousands of taste buds
located at the posterior

Question 11

foliate papillae

Answer 11

elongated structure
contain hundreds of taste buds
lie along posterior lateral edge

Question 12

fungiform papillae

Answer 12

contain one or two taste buds

widespread across anterior portion and tip of tongue