Human phys II Flashcards
1
Q
how is the series elastic component formed?
A
tension generated by sarcomeres is transmitted to bone via tendons
2
Q
isotonic contraction
A
constant load
muscle changes length
3
Q
isokinetic contraction
A
velocity remains the same, muscle changes length
4
Q
isometric contraction
A
tension changes and muscles change length
5
Q
what is graded contraction and what are the primary factors behind it
A
varying force generation in a whole muscle,
1) #of muscle fibers
2) tension developed by each fiber
6
Q
can a motor neuron innervate multiple neurons? what is a motor unit?
A
yes
all of the fibers associated with a motor neuron
7
Q
what influences muscle tension?`
A
frequency of stimulation, resistance to fatigue, length of fiber at onset, thickness of fiber
8
Q
hydrostatic pressure
A
pressure exerted by stationary fluid on its container
9
Q
What is the main determinant of cell osmolarity and what is the concentration?
A
Na, sodium and 135-145mEq/L
10
Q
hyponatremia and hypernatremia
hypo vs hyperosmotic solution>?
A
too little and too much sodium
too little solute out of cell and too much
11
Q
normal cell osmolarity
A
300mOsm
12
Q
tonicity
A
the effect a solution has on a cell’s volume due to non-permeable solutes
13
Q
Features of carrier proteins
A
always open, are based on solute affinity, slower than carriers, facilitated transport, no ATP use
14
Q
4 steps of contraction that require ATP
A
myosin ATPase site (E for power stroke)
ATP binding releasing mysoin from cross-bridge
Active transport of Ca back into SR via SERCA pumps
Na/K pump
15
Q
What 3 major pathways prove muscle with ATP?
A
creatine phosphate makes ADP->ATP
oxidative phosphorylation
glycolysis
16
Q
1st source of ATP, runs out quickly ~
A
creatine phosphate
17
Q
slowest ATP
A
oxidative phosphorylation, requires Oxygen
(ATP)
18
Q
When does glycolysis happen?
A
when oxidative phosphorylation cannot keep up with demand (lasts around 2 minutes)
makes lactate
19
Q
what is fatigue for and what causes it?
A
to prevent muscles from tensing and being unable to relax, its a defense mechanism
1 increase of inorganic phosphate
2 calcium leakage out of cell
3 depletion of glycogen stores
20
Q
what are the three major types of skeletal muscle fibers?
A
slow oxidative (I)
fast oxidative (IIa)
fast glycolytic (IIx)
21
Q
why are fast fibers fast?
A
more myosin ATPase
22
Q
Oxidative vs glycolytic fibers
A
oxidative have lots of mitochondria and myoglobin
23
Q
smooth muscles
A
innervated by autonomic nervous system
dont use troponin
long spindle shaped
24
Q
smooth muscle locations
A
blood vessels, guts, reproductive orgs, urinary tract, airways
25
Dense bodies are what?
bundles of intermediate filaments with actin anchored to them
look like fishnet pattern, when they all contract the muscle cell scrungles inwards
26
thin vs thick actin filaments
contain tropomyosin but not troponin
the tropomyosin instead regulated and increases myosin ATPase
thick contain myosin light chain that need to be phosphorylated before myosin can bind to actin
27
Myosin light chain process
Ca++ activates calmodulin
Calmodulin activates myosin light chain kinase (MLCK)
hydrolyzes ATP to phosphorylate myosin light chain kinase
28
how is Ca++ regulated and released in smooth muscle?
depolarization opens V-gated channels on PM, release is from the SR
Calcium induced calcium release (CICR): calcium binds to ryanodine receptors
(^common in phasic smooth muscle)//
activation of G protein-coupled receptors release second messenger IP3 -> IP3 opens IP3-gated channels on SR
(^common in tonic smooth muscle)//partially contracted state
29
what re-sequesters Ca++ in SM?
SERCA pumps
30
multi-unit vs single-unit SM
multi; each individual cell gets neural input, each muscle cell can act independently, fine control
single; only some cells get neural input, cells have gap junctions, coordinate contraction
31
two types of myogenic excitation potentials
pacemaker and slow wave potentials
slow wave; modulation of membrane potential underneath threshold// only in stomach
pacemaker; gradually depolarize until AP and repeat
32
What are interneurons
99% of neurons
only in Central Nervous System (CNS)
associated with complex actions
33
Astrocytes
most abundant glial cell
maintain spatial relationships b/w neurons
maintain blood/brain barrier
guide neurons in development
34
microglia
immune cells f CNS
either stimulated (round) or unstimulated (wispy)
phagocytose nearby cells then send out cytokines
35
Ependymal cells
stem cells of brain
aids in injury repair
produce cerebrospinal fluid that cushions brain.
36
Glioma
glial cell brain tumor
37
Amitotic
neuronal cells are this;; undividing
38
cerebral cortex
voluntary movement
higher sensation, intellect
39
Basal Nuclei
procedural learning/ habits
40
thalamus
onset of sensory perception
41
hypothalamus
homeostasis
42
cerebellum
propriocepition
43
brain stem
Life-Sustaining vegetative functiosn
44
Corpus callosum
connect two halves o brain
45
white vs gray matter
bundles of myelinated nerves
densely packed neuronal cell bodies/their dendrites and most glial cells
46
4 lobes of cerebral cortex
occipital // visual
temporal // auditory
parietal // receiving and processing sensory input
frontal // voluntary motor activity, speech,
47
within parietal lobe theres ___ ____
primary and somatiosensory cortexes
movement and sensation are with these
48
Homunculus
parts of body exaggerated on brain // leading to differences on sensitivity
49
spinal cord structure
gray matter inside white matter outside
50
ascending vs descending tracts
ascending // info to brain (afferent)
descending // info from brain (efferent)
51
Reflex categories
spinal v cranial
innate v conditioned
somatic v autonomic
mono v polysynaptic
52
steps of reflex arc
sensory receptor -> afferent pathway -> integration center -> efferent pathway -> response by effector
53
3 horns of ANS
Lateral // afferent neurons terminate onto these
Dorsal // cell bodies of autonomic efferent nerve fibers
Ventral // ..of somatic efferent neurons
54
Parts of spinal nerves
dorsal and ventral roots
attached to dorsal root ganglion
55
number of nerve pairings (spinal and cranial)
31 pairs of spinal nerves
12 pairs of cranial nerves
56
monosynaptic vs polysynaptic reflex
1 vs multiple synapses in spinal cord
interneurons connect afferent and efferent neurons in poly
mono-stretch reflex
poly-withdrawal reflex and crossed extensor reflex (maintain balance)
57
what do muscle spindles do, what type of specialized fibers do they have?
muscle spindles monitor length of muscle fibers
they have intrafusal fibers
58
what is special about intrafusal fiber neurons? which are what?
efferent; gamma motor neurons
afferent; primary (change of length and speed of change) and secondary (length only)
59
what allows muscle spindles to retain sensitivity even when the muscle is shortened?
alpha-gamma coactivationm
60
mechanism of stretch reflex
when passive stretch happens; gamma afferent neurons synapse on the alpha neurons to resist change
61
how can gamma help alpha>?
if gamma signal doesn't get intended muscle shortening , alpha can reflexively increase force
62
withdrawal reflex pathway
stimulus -> afferent pathway -> integration center -> excitatory and inhibitory interneurons signal and brain is sent a signal too -> efferent pathway
63
what is reciprocal innervation
contracting of one muscle group relaxes another
64
cross extension reflex
hurt appendage is withdrawn and other stabilizes balance
65
golgi tendon organ
are in muscle tendons to detect tension
66
where do somatic efferent fibers start and end?
originate in CNS and terminate on effector organ
67
Autonomic efferent fibers
CNS neurons with pre-ganglionic fiber sends signal to autonomic ganglion which sends down post-ganglionic fiber
68
what are the two divisions of the Autonomic nervous system and what do they address?
sympathetic; fight or flight
parasympathetic; rest and digest
69
Where do sympathetic preganglionic fibers originate?
thoracic and lumbar regions of spinal cord
70
sympathetic pre and post ganglionic fibers are
very short and very long respectively
adrenal medulla has no postganglionic :o
71
Where do parasympathetic preganglionic fibers originate?
cranial and sacral (lower spinal cord)
72
sympathetic pre and post ganglionic fibers are
very long and very short respectively
pre-g terminate in terminal ganglia
73
ANS neurotransmitters
ALL pre-g fibers release nts Ach
post-g depend on
sympathetic; noradrenaline
parasympathetic; Ach
74
How do different cell PM receptors react to ANS NTS?
Ionotropic; if ion flow
Metabotropic; signal thru G-protein coupled receptors, which activate second messengers
75
ANS receptors and what they do (cholinergic)
Cholinergic;
nicotinic-ionotropic, respond to ACh
Muscarinic-metabotropic, respond to ACh from parasympathetic post-g
76
ANS receptors and what they do (adrenergic)
all metabotropic (1s excite 2s inhibit)
a1 a2 b1 b2
77
Dual innervation
most organs innervated by both ANS divisions
exception; arterioles and veins and sweat glands SYMP only
78
3 main specialized elements of blood
1 erythrocytes
2 leukocytes
3 platelets
79
plamsa
90% water
80
albumins
most abundant plasma protein
contribute to colloid osmotic pressure
81
Globulins
help transport poorly soluble substances, help in blood clottings, and can act as antibodies
82
Fibrinogen
blood clotting!
83
all about erythrocytes
empty except for hemoglobin,
glycolytic enzymes; make E for active transport and maintaining ionic gradients
and carbonic anhydrase; binds CO2 and catalyzes CO2->bicarbonate
84
Erythropoiesis
generation of new erythrocytes due to each old one dying after 120 days
RBCs made from red blood marrow and are stimulated by erythropoietin
85
Erythropoiesis steps
1) pluripotent stem cell
2) myeloid stem cell
3) erythroblast
4) reticulocyte
5) erythrocyte
86
response by body from low RBC or hemoglobin count
sensed by kidneys, body releases erythropoietin into blood
87
Anemia and its types
below normal oxygen carrying capacity
nutritional; dietary lack
pernicious; lack of vitamin B12
aplastic; bone marrow can't make enough
renal; results from kidney disease (no EPO)
hemorrhagic; blood loss
hemolytic; rupture of circulating RBCs
88
Polycythemia
definition, primary vs secondary
too many circulating RBCs == elevated hematocrit
primary // bone marrow issue
secondary // chronic reduction in O2 tissue delivery
89
relative polycythemia
dehydration
90
Type A blood has what antigens and what antibodies
B antibodies
A antigens
91
3 tasks of leukocytes
1) defend against invading evil microorgs
2) remove worn out cells and tissue debris
3) identify + destroy cancerous cells
92
two main categories of the 5 types of leukocytes
mononuclear agranulocytes
and polymorphonuclear granulocytes
93
polymorphonuclear granulocytes
Eosinophils; allergic reactions and parasite infections
basophils; Heparin (anticoagulant) release and histamine (vasodilator)
neutrophils; engulf and destroy bacterios
94
mononuclear agranulocytes
monocytes; released immature from bone marrow --- mature into mature macrophages
lymphocytes; targeted immune response
95
two types of immune defense provided by lymphocytes
Humoral immunity; made by B-lymphocytes and are antibody mediated
Cell-mediated immunity; cells destroy target directly, mediated by T-lymphocytes
96
what do lymphoid tissues do?
produce, store, or process lymphocytes
97
what does the lymph system do? The spleen?
replaces RBCs in blood stream with leukocytes
Vice versa.
98
Thymus purpose
T-cell maturational processing
99
Never Let Monkeys Eat Bananas
Neutrophils, Lymphocytes, Monocytes, Eosinophils, Basophils in order of prevalence
100
what are platelets made from
undifferentiated pluripotent stem cells -> megakaryocytes -> platelets (budded-off pieces of previous)
101
platelet info
have organelles to produce secretory products
last 10 days
production of platelets is stimulated by thrombopoietin from liver
helps clot blood
102
3 major steps of blood clotting
vascular spasm (torn vessels constrict immediately)
platelet plug formation (VWF adheres to collagen and allows platelets to bind)
blood coagulation (transformed blood goes from a liquid to a solid)
103
what do the already bound platelets do in blood clotting?
produce ADP and tA2 to activate their fellows
104
What does releasing prostacyclin and nitric oxide do?
limits aggregation, and nearby epithelial cells turn off platelets
105
what is the main step of blood coagulation and how do it do????
conversion of fibrinogen to fibrin via thrombin catalyzing it
fibrin form a net and factor XIII allows for cross-linking
106
Interferons
released by virus-infected cells to inhibit viral multiplication of other cells
107
