Physiology

Regulatory protein that overlaps binding sites on actin for myosin and inhibits interaction in the relaxed state

tropomyosin

Binding of _______ moves tropomyosin away and allows myosin to interact with the actin

Ca2+

Sarcomere

Sarcomere shortened

-Z lines move closer
-H band shortens
-I band shortens
-A band unchanged (myosin)

Troponin (on actin) binding sites

myosin, tropomyosin, calcium

homologous to the sarcoplasmic reticulum in most cells - Ca2+ is stored and release following membrane excitation

sarcoplasmic reticulum

the motor neuron and the skeletal muscle fibers it innervates

motor unit

enzyme that breaks down Ach

acetylcholinesterase

True/false: all NMJ are inhibitory

false - excitatory

increase in muscle tension from successive action potentials occurring during the phase of mechanical activity

summation

maintained contraction in response to repetitive stimulation - maximal tension is produced and increasing number of stimuli has no effect on tension production

tetanus

time between application of a stimulus and the beginning of a contraction in a muscle fiber

latent period

is it possible for a second AP to be initiated before complete relaxation in skeletal muscle?

yes

a springy protein that is responsible for the passive elastic properties of relaxed muscle fibers, links myosin to z-line

titiin

slow oxidative fibers

Type I fibers

fast oxidative fibers

Type IIa

fast glycolytic fibers

Type IIb

Diameter of type I muscle fibers

small

Diameter of type IIb muscle fibers

large

Which muscle fibers are recruited first?

type I

which muscle fiber has the highest resistance to fatigue?

type I

which muscle fiber fatigues the fastest?

type IIb

muscle fibers for aerobic activity

type I

muscle fibers for long-term anaerobic activity

type IIa

muscle fibers for short-term anaerobic activity

IIb

muscle fibers that produce the greatest amount of force

IIb

muscle fiber with highest myoglobin content

I

muscle fiber with highest mitochondrial content

I

what chromosome is affected in DMD?

X

protein involved in DMD

dystrophin

protein that connects the sacrolemma to the actin

dystrophin

autoimmune destruction of nicotinic Act receptor proteins of the motor end plate

myasthenia gravis

what muscle is single-nucleated?

cardiac, smooth

what muscle is multinucleated?

skeletal

smooth muscle does not have what protein?

troponin

what is cross-bridge cycling in smooth muscle regulated by?

myosin light chain kinase

True/false: input to smooth muscle can be inhibitory or excitatory

true

mildest form of injury. conduction block usually due to myelin dysfunction. axonal continuity conserved. nerve conduction is preserved proximal and distal to lesion. nerve fibers are not damaged. recovery will occur within 4/6 weeks.

neurapraxia

Axonotmesis

axonal damage, intact connective tissue coverings; wallerian degeneration occurs; muscle atrophy occurs; due to prolonged compression

complete severance of a nerve resulting in permanent loss of function

neurotmesis

what is the precursor of steroid hormones?

cholesterol

what is the precursor of amine hormones?

Tyrosine

what class of hormone is: dopamine?

amine

What class of hormone is aldosterone?

steroid

What class of hormone is cortisol?

steroid

what class of hormone is: testosterone?

steroid

what class of hormone is: thyroid?

amine

what class of hormone is: catecholamines (epi/norepi)?

amine

what class of hormone is: estrogen?

steroid

what class of hormone is: DHEA?

steroid

what 2 locations primarily produce steroid hormones?

gonads and adrenal cortex

lipid or water soluble: thyroid

lipid

lipid or water soluble: steroids

lipid

lipid or water soluble: catacholamines

water

lipid or water soluble: peptides

water

receptors inside or outside cell: catecholamines/peptides

outside

receptors inside or outside cell: steroids and thyroid

inside

hormone that controls the secretion of another hormone

tropic

the hypothalamus has control over what?

ant/post pitutiary

ant/post pituitary: vasopressin

posterior

ant/post pituitary: oxytocin

posterior

ant/post pituitary: GH

anterior

ant/post pituitary: LH + FSH

anterior

ant/post pituitary: TSH

anterior

ant/post pituitary: prolactin

anterior

ant/post pituitary: ACTH

anterior

inhibits secretion of prolactin

dopamine

simulates release of LH + FSH

GnRH (gonadotropin-releasing hormone)

inhibits secretion of GH

SS (somatostatin)

stimulates release of GH

GHRH (growth hormone-releasing hormone)

stimulates secretion of TSH

Thyrotropin-releasing hormone (TRH)

stimulates secretion of ACTH

corticotropin-releasing hormone (CRH)

what is important in the diet for thyroid function?

iodine

hormones from the hypothalamus that regulate ant. pituitary gland function

hypophysiotropic hormones

t3

triiodothyronine

t4

thyroxine

hyperthyroidism alternate name

graves

hypothyroidism alternate name

hashimotos

what is the stress hormone?

cortisol

general term for when plasma levels of cortisol are chronically lower than normal

adrenal insufficiency

general term for when plasma levels of cortisol are chronically higher than normal

cushing's disease

main concerns for adrenal insufficiency

blood glucose + pressure control

primary adrenal insufficiency alternate name

addisons disease

Parathyroid hormone is critically important for _____ levels.

Ca2+

where are the 3 areas of ca2+ storage?

bone, intestines, kidneys

what are the 3 hormones that help regulate plasma ca2+ conc'?

calcitonin (minimal), vitamin D, PTH

condition in which bone mineralization is deficient - often from vitamin D deficiency

rickets/osteomalacia

Mullerian ducts

female

wolferian ducts

male

all estrogens are converted from androgens via.

aromatase

A chromosomal disorder in which males have an extra X chromosome, making them XXY instead of XY

Klinefelter syndrome

transport urine from kidneys to bladder

ureters

carries urine from the bladder to the outside of the body

urethra

functional unit of the kidney

nephron

what is secreted when a drop in BP is detected?

renin

Renin converts _______ to _________.

angiotensinogen to angiotensin I

Angiotensionogen is secreted from?

liver

Angiotensin I is converted to angiotensin II by

ACE in the lungs

When this is secreted, there is increased sodium reabsorption, water follows, blood volume increases, and BP increases

aldosterone

where does the majority of reabsorption occur?

loop of henle, proximal tubule

reabsorption of Na2+ is
active
and cannot be reabsorbed in the ?

descending loop of henle

Ca2+ reabsorption is increased by

parathyroid hormone