FINAL EXAM: Unit 3 Flashcards by AMANDA KUEHNER

describe the structure of sympathetic neurons in the autonomic NS. what do they release? where are they located on the spine?

thoracic & lumbar region
-pregang: short, release ACh (N(N), nico)
-autonomic gang: close to SC
-postgang: long, release NE (alpha, beta)

How well did you know this?

Not at all

Perfectly

describe the structure of parasympathetic neurons in the autonomic NS. what do they release? where are they located on the spine?

brainstem & sacral
-pregang: long release ACh (N(N), nico)
-autonomic gang: close to effector
-postgang: short, release ACh (musc)

How well did you know this?

Not at all

Perfectly

what is the neuroeffector junction? what is the pathway at the neuroeffector junction?

synapse b/w postgang & effector, end in varicosities
1. AP reaches varicosity
2. depolarization
3. Ca2+ release
4. exocytosis
5. NT release
6. postsynapse

How well did you know this?

Not at all

Perfectly

what is special about the neurons in the adrenal medulla?

lacks axons, no postganglia

How well did you know this?

Not at all

Perfectly

what breaks down NE? what breaks down ACh?

MAO: breaks down NE
acetylcholinesterase: breaks down ACh

How well did you know this?

Not at all

Perfectly

what is a direct agonist/antagonist?

mimic/block NT action

How well did you know this?

Not at all

Perfectly

what is an indirect agonist/antagonist?

alters secretion, reuptake, or degradation of NT

How well did you know this?

Not at all

Perfectly

describe the neurons in the somatic NS

only 1 neuron b/w CNS and effector
-skeletal muscle

How well did you know this?

Not at all

Perfectly

what is the neuromuscular junction? what is the pathway at the neuromuscular junction?

synapse b/w motor neuron & muscle
1. AP reaches terminal
2. depolarization
3. Ca2+ entry
4. ACh release
5. binds N(M) receptor
6. net Na+ entry
7. depolarization
8. AP causes muscle contraction

How well did you know this?

Not at all

Perfectly

what is the hearts sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: beta 1 -> increased HR
PARASYMP: musc -> decreased HR

How well did you know this?

Not at all

Perfectly

what is the blood vessels sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha -> constrict, beta -> dilate
PARASYMP: NONE

How well did you know this?

Not at all

Perfectly

what is the bronchioles sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: beta 2 -> dilation
PARASYMP: musc -> constrict

How well did you know this?

Not at all

Perfectly

what is the GI tracts sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha 2 -> decrease motility & secretions
PARASYMP: musc -> increase motility & secretions

How well did you know this?

Not at all

Perfectly

what is the bladders sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha 1 -> relax (retention)
PARASYMP: musc -> contract (empty)

How well did you know this?

Not at all

Perfectly

what is the pupils sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha 1 -> dilate
PARASYMP: musc -> contract

How well did you know this?

Not at all

Perfectly

what is the cilliary muscles sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha 1 -> relax (flat lens)
PARASYMP: musc -> contract (round lens)

How well did you know this?

Not at all

Perfectly

what is the sweat glands sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha 1 -> increase secretion
PARASYMP: NONE

How well did you know this?

Not at all

Perfectly

what is the adipose tissue sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha -> breakdown
PARASYMP: NONE

How well did you know this?

Not at all

Perfectly

what is the adrenal medullas sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: no receptor -> secrete E
PARASYMP: NONE

How well did you know this?

Not at all

Perfectly

what is insulins sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha 2 -> decrease secretion
PARASYMP: musc -> increase secretion

How well did you know this?

Not at all

Perfectly

what is the genitals sympathetic NS receptor and effect? parasympathetic receptor and effect?

SYMP: alpha 1 -> orgasm
PARASYMP: musc -> erection

How well did you know this?

Not at all

Perfectly

what are the two fibers in a sarcomere?

myosin: thick, heavy & light chains, ATPase activity
actin: thin, troponin & tropomyosin

How well did you know this?

Not at all

Perfectly

what is the Z-disk?

attachment for actin

How well did you know this?

Not at all

Perfectly

what is the I-band?

length of ONLY actin, spans into next sarcomere

How well did you know this?

Not at all

Perfectly

what is the A band?

entire length of myosin

what is the H zone?

in the middle, length of ONLY myosin

what is the M line?

MIDDLE, myosin attachment site

what is titin?

elastic, stabilizes contractile fibers

what is nebulin?

inelastic, stabilizes actin

what is the process of muscle contraction during the neuromuscular junction phase?

1. AP reaches motor neuron 2. Ca2+ entry 3. exocytosis 4. ACh release 5. binds nicotinic receptors 6. net Na+ entry

what is the process of muscle contraction during the excitation-contraction coupling phase?

7. AP reaches T-tubule 8. activates DHP receptor -> Ca2+ release 9. SR opens RyR channels -> Ca2+ release 10. troponin 11. tropomyosin moves off myosin binding site 12. powerstroke

what is the process of muscle contraction during the powerstroke?

1. myosin binds to actin 2. ATP binds 3. myosin releases 4. myosin head cocks 5. Ca2+ activates myosin's powerstroke 6. Pi released 7. ADP released 8. myosin back to rigor state

what is the process of muscle contraction during the contration-relaxation cycle?

13. crossbridge forms 14. I and H bands shorten 15. sarcomere overall shortens and contracts 16. Ca2+ ATPase pumps Ca2+ back into SR 17. tropomyosin binds to myosin binding site 18. ACh degraded

what are the three ways ATP is supplied?

phosphocreatine: fastest, donates a phosphate oxidative phosphorylation: makes the most anaerobic glycolysis: when O2 is low

what is the difference b/w central and peripheral fatigue?

central: psychological peripheral: physiological

what are the three types of muscle fibers? what are examples of movements associated with each?

slow-twitch (Type 1): posture fast-twitch oxidative-glycolytic (Type 2A): standing, walking fast-twitch glycolytic (Type 2X): jumping, sprinting

which of the fiber types are fatigue resistant?

Type 1 & 2A

which of the fiber types use aerobic? which are anaerobic?

aerobic: Type 1 & 2A anaerobic: Type 2A & 2X

which fiber type has the highest level of capillaries, mitochondria, and myoglobin?

Type 1

what does it mean when there are more fast motor units? what about more slow motor units?

fast units: more tension slow units: less tension, endurance

describe the motor units for fine movement

more units less fibers per neuron more tension

describe the motor units for gross movement

less units more fibers per neuron less tension

what is the difference between isotonic and isometric contractions?

isotonic: force and movement isometric: force w/o movement

what is the difference between concentric and eccentric movements?

concentric: muscle shortens, flexing eccentric: muscle lengthens, extending

which of the three muscle types (skeletal, smooth, cardiac) are striated?

skeletal & cardiac

which of the three muscle types (skeletal, smooth, cardiac) has no sarcomeres, t-tubules, or troponin?

smooth

which of the three muscle types (skeletal, smooth, cardiac) gets its Ca2+ from the ECF & SR?

smooth & cardiac -skeletal gets Ca2+ from just the SR

which of the three muscle types (skeletal, smooth, cardiac) is controlled by the autonomic NS?

smooth & cardiac -skeletal controlled by somatic NS

describe the contraction pathway for smooth muscle

1. Ca2+ entry from ECF 2. Ca2+ entry from SR 3. Ca2+ binds calmodulin 4. activates myosin light chain kinase 5. phosphorylation of myosin light chains 6. cross-bridge and powerstroke 7. contraction

describe the relaxation for smooth muscle

1. Ca2+ ATPase pumps Ca2+ into ECF & SR 2. dephosphorylation of myosin light chains

what triggers the SR to release Ca2+?

Ca2+ induced (due to ECF Ca2+ release) IP3 mediated

what triggers ECF Ca2+ release?

Ca2+ channels (voltage, ligand, stretch)

what does histamine and NO do to smooth muscle?

histamine: contract NO: relax

what are muscle spindles?

respond to stretch -contain intrafusal fibers -ENDs: contractile, efferent signals, gamma motor neurons -MIDDLE: noncontractile, afferent signals, alpha motor neurons

what is the stretch reflex pathway?

1. stretch in extrafusal fibers 2. detected by muscle spindle 3. afferent signal to SC 4. alpha neuron goes to extrafusal fibers to contract extensor 5. gamma neuron goes to muscle spindle to contract in proportion

what is reciprocal inhibition pathway?

1. tap tendon -> spindle -> afferent to SC 2. alpha neuron contracts quad (monosynaptic) 3. inhibitory alpha neuron relaxes hamstring (polysynaptic)

what is the flexion reflex pathway?

1. pain on RIGHT side of body -> spindle -> afferent to SC 2. alpha neuron contracts RIGHT flexor 3. inhibitory alpha neuron relaxes RIGHT extensor 4. alpha neuron contract LEFT extensor 5. inhibitory alpha neuron relaxes LEFT flexor

describe the three types of movement (reflex, voluntary, rhythmic)

reflex: external stimuli, integrated in SC voluntary: external stimuli & will, cerebral cortex rhythmic: will, SC & cerebral cortex

what does the spinal cord do for movement? what part of movement is it responsible for?

spinal reflexes, CPGs (maintain movement after initation), cross over in corticospinal tract -executing movement

what does the brainstem do for movement? what part of movement is it responsible for?

posture, hand & eye movements -executing movement

what does the cerebral cortex do for movement? what part of movement is it responsible for?

planning & coordinating voluntary movement, senses -decision-making & planning, initiating movement

what does the cerebellum do for movement? what part of movement is it responsible for?

adjusts voluntary movement & monitors, balance -decision-making & planning, executing movement

what does the thalamus do for movement?

relay station for cerebral cortex

what does the basal ganglia do for movement? what part of movement is it responsible for?

motor planning & feedback to thalamus, releases DA -decision-making & planning

describe the corticospinal tract pathway

1. descending tract 2. brainstem 3. cross over in medulla pyramids 4. alpha motor neurons 5. SC