Exam 1 Flashcards
(187 cards)
1
Q
What connects nerves to their effectors?
A
Peripheral motor endings
2
Q
Where are motor endings found? What do they do?
A
Peripheral Nervous System (PNS)
They release neurotransmitters
3
Q
What type of movement does innervation of skeletal muscles create? From what part of the PNS?
A
Voluntary Movement
Somatic Nervous System
4
Q
Innervation of skeletal muscles: Where is Ach released?
A
Released at a synapse called the neuromuscular junction (NMJ)
5
Q
Innervation of Viceral Muscles and glands from what part of the PNS?
A
Autonomic NS
6
Q
Innervation of Visceral Muscles and Glands: What is released and where?
A
Ach or Norepinephrine at varicosities
7
Q
What are the three levels of motor control?
A
Segmental, Projection, and Precommand
8
Q
The Segmental Level of Motor Control
A
-Spinal cord segment level
-motor neurons in ventral horn and interneurons
-final outputs for muscle movement; reflex circuits
–segmental level important for pattern movement
9
Q
area of the brain involved in The Segmental Level of Motor Control
A
-motor neurons in ventral horn and interneurons
10
Q
The projection level
A
-motor cortex (+axons to spinal cord)
-“upper motor neurons” that command voluntary movements
11
Q
area of the brain involved in the The projection level
A
-motor cortex (+axons to spinal cord)
12
Q
the precommand level
A
-cerebellum and basal nuclei
–influence motor cortex and help refine movements
13
Q
Reflex activity are…
The reflex arc enables…
A
quick movements
rapid and predictable responses
14
Q
Reflexes are…
A
involuntary, stereotyped responses to stimulus (movements)
15
Q
Components of a reflex arc
A
-Pathway of neurons that are responsible for the movement
Receptor-> afferent-> integration center w/ interneurons-> motor efferent-> effector muscle
16
Q
What are spinal reflexes?
A
somatic reflexes mediated by the spinal cord
(can occur without direct involvement of higher brain areas)
17
Q
Stretch reflex
A
External stimulus creates the stretch- the reflex is contraction
18
Q
Goal of the stretch reflex
A
keep posture with external stimulus
-when muscle X is stretched by something it reflexively contracts and at the same time motor neurons antagonist to muscle X (muscle Y) are inhibited
19
Q
ARC steps with stretch reflex
A
- Muscle spindle detects stretch
- spindle afferent excite muscle X motor neuron and interneuron (interneuron inhibits antagonist motor neurons)
20
Q
What are the effectors of the somatic nervous system?
A
skeletal muscles
21
Q
What are the effectors of the autonomic nervous system?
A
smooth muscle, heart, glands
22
Q
Where are the cell bodies of neurons in the somatic N.S.
where do their axons extend?
A
spinal cord
to the skeletal muscle they innervate
23
Q
where do the axons of neurons in the somatic NS extend to?
A
the skeletal muscles they innervate
24
Q
The ANS consists of (in terms of efferent pathways and ganglia)
A
A two neuron chain
The 1st neuron: preganglionic; its soma in the CNS, its axon terminates in a ganglion
The 2nd neuron: postganglionic neuron; its soma in the ganglion, its axon terminates on effector (w varicosities)
25
1st neuron in the ANS
(where is its soma, where does its axons terminate, pre or postganglionic)
preganglionic; its soma in the CNS, its axon terminates in a ganglion
26
2nd neuron in the ANS
postganglionic neuron; its soma in the ganglion, its axon terminates on effector (w varicosities)
27
what neurotransmitter is released by somatic motor neurons
acetylcholine
28
What do the neurotransmitters in the ANS within ganglia release? what does it do?
releases ACh from preganglionic cell which excites the postganglionic cell
29
what does acetylcholine do?
excites skeletal muscle
30
What do the neurotransmitters in the ANS releases at effector?
the preganglionic releases EITHER ACh or NE which may excite or inhibit effector
31
What are the two divisions of the ANS
parasympathetic and sympathetic divisions
32
Both divisions of the ANS usually serve the same visceral organs, but....
cause opposite effects
33
the parasympathetic division is manly known to
be lower energy spending
"rest and digest"
34
the sympathetic division is mainly known two
govern
"fight or flight" to threat
35
sympathetic and parasympathetic divisions differ in anatomy..
site and origin in the CNS and location of ganglia (therefore axon length)
36
Long preganglionic parasympathetic fibers originate in the?
Craniosacral CNS
37
preganglionic axons extend...
From CNS almost all the way to terminal ganglia at or near effector
38
cranial part of parasympathetic division...
sends preganglionic axons by way of cranial nerves, especially by the vagus nerve (CN 10)
39
sacral part of parasympathetic divisionn sends axons...
sends axon in nerves to digestive, urinary, and reproductive organs in lower abdomen
40
short preganglionic sympathetic fibers originate in the...
thoracolumbar CNS
41
in addition to innervating visceral organs in internal body cavities, sympathetic neurons exclusively innervate..?
superficial structures such as..
sweat glands, arrector pili, and smooth muscle in blood vessels
42
sympathetic pregang neurons exit the spinal cord via the..
ventral root
43
all sympathetic ganglia are located
close to the spinal cord (thus, the postganglionic axons are long)
44
ACh and NE are the major____ transmitters
ANS
45
Cholinergenic Receptors include
nicotinic and muscurinic
46
Nicotinic cholinergic receptors are found
on postganglionic neurons (and on skeletal muscles) and are excitatory
47
muscarinic receptors occur
on parasympathetic effector cells and may be excitory or inhibitory
48
there are two classes of adrenergic receptors that
produce either an excitory or inhibitory responses
49
the para and sym divisions usually produce...
opposite effects
50
most visceral organs receive...
dual innervation by both ANS divisions
51
iris dual innervation
Para- Constriction
Sym- Dilation
52
gastric gland dual innervation
Para- increase secretion
Sym- Decrease secretion
53
heart dual innervation
Para- Slows heart rate
Sym- Increase heart rate and squeeze more
54
bronchioles dual innervation
para- constricts
sym- dialates
55
sympathetic tone throughout the vascular system allows..
the firing of sympathetic neurons to control the diameter of BLOOD VESSELS, regulating systemic blood pressure
56
parasympathetic tone is usually dominant in the
HEART, DIGESTIVE SYSTEM, and URINARY TRACTS, maintaining normal homeostatic levels of function unless overridden by the sympathetic system during stress
57
what effect do the ANS divisons show on the genetalia
cooperative effect
58
the sympathetic system has a unique role in
thermoregulation: sweat glands, arrector pili
vascular- constricts skin blood vessels (it dialates other blood vessels)
kidney/ hormones- renin release
59
the sympathetic system has a unique role in ther omoregulation by
sweat glands and arrector pili
60
the sympathetic system has a unique role in the vascular system by
contricting skin blood vessels (usually dialates other blood vessels)
61
the hypothalumus oversees
ANS activity
62
what has the most direct influence over autonomic functions
the brain stem
63
the sympathetic system has a unique role in the kidneys/ hormones by
renin release
64
what is the main integration center for the ANS
hypothalamus
65
partial control or voulentary control of the ANS may be possible becuase
biofeedback training may enable a person to alter some invoulentary functions
66
brain stuctures involved in precommand level
-cerebellum and basal nuclei
67
the endocrine system is one of the bodys two...
main control systems
68
endocrinology is the study of
hormones and endocrine organs
69
hormones are
blood borne chemical messengers
70
hormone targets include
most cells in the body but the cell must have specific receptors: when hormone binds to the receptor cellular metabolism changes
71
What happens when a hormone binds to a receptor
cellular metabolism changes
72
endocrine glands are
examples are?
organs that secrete and make hormones, are ductless
include pituitary, thyroid, adrenal, etc. but many organs have some endocrine function
73
the chemical structure of a hormone determines
how it acts
74
most hormones are....
but other hormones are...
Where do lipid soluable steroids come from?
amino-acid based and water soluable
lipid soluable steroids such as those from gonads and adrenal cortex
75
the chemical structure of a hormone impacts its solubility in water which then impacts
its transport in blood, how long it stays in the body, which receptors it binds to
76
hormones act through....
second messengers or by activating specific genes
77
hormones can only influence target cells which are cells that
have receptors for that specific horomone
78
water soluable hormones use
plasma membrane receptors and second messenger systems
79
The cyclic AMP singaling mechanism
a) hormone binds receptor (on membrane surface)
b) receptor activates g-protein
c) g-protein activates adenyl cyclase (AC)
d) AC makes cAMP
e) protein kinase adds G (guanine) to a protein (eg. an ion chanel protein)
80
other signaling mechanisms use
different second messengers or work without second messengers to initate a certian cellular responses
81
lipid soluable hormones use
intracellular receptors and specific gene activation
82
direct gene activation occurs when
sterioids or thyroxine binds to intracellular receptors and then activate a segment of DNA , i.e, start transcription (start protein synthesis)
83
What are the three types of stimuli that cause hormone release?
A) Hormone sythesis and release is regulated
B) Endocrine gland stimuli may be humoral, neutral, or hormonal
C) Feedback control
84
Endocrine gland stimuli may be
humoral, neutral, or hormonal
85
stimuli that cause hormone release
critical ions or nutrients (humoral)
+ example
high or low levels of a chemical trigger hormone secretion
EG. low Ca++ PTH release
86
stimuli that cause hormone release
if autonomic (neural)
axons release neurotransmitters to trigger hormone secretion (E.g sympathetic axons releasing adrenaline)
87
stimuli that cause hormone release
if one hormone (hormonal)
+ example
one hormone stimulates a gland so secrete another hormone
(e.g TSH-TH)
88
stimuli that cause hormone release
Feedback control + Exp
1) a hormone in the blood often inhibits subsequent release
(e.g. TH inhibits pituitarys release of TSH
89
cells respond to a hormone if they have....
receptors for that hormone
90
target cell response depends on three factors....
blood levels of the hormone
reletive number of target cell receptors
affinity of the the receptor for the hormone
91
target cells can change their sensitivity to a hormone by
changing the number of receptors
92
target cells can change their sensitivity to a hormone by changing the number of receptors
UP REGULATION
cell becomes more sensitive by expressing more receptors
93
target cells can change their sensitivity to a hormone by changing the number of receptors
DOWN REGULATION
cell makes less receptors (so becomes less sensitive)
94
Half life is
how long before the hormone is excreted or inactivated
95
Is half life shorter for water soluble hormones or lipid soluable hormones
water soluable hormones
96
Duration of hormonal activity: do water soluable hormones or steriods act quicker?
Water soluable
97
Interaction of hormones at target cells include
synergysm and antagonism
98
Interaction of hormones at target cells
SYNERGISM
when 2 hormones interact on a target cell causing a large effect (eg. cortisol + adrenaline)
99
Interaction of hormones at target cells
ANTAGONISM
when two hormones oppose each other
(eg. insulin vs glucagon)
100
the hypothamus controls release of hormones from the
pituitary gland
101
the pituitary gland is situated in the.... of the skull and is connected to the ... by the...
STELLA TURICA...BRAIN...INFUNDIBULUM
102
What are the two lobes of the pituitary
Anterior Pituitary: several hormones
Posterior Pituitary: two hormones (no true grandular cells
103
the hypothalamic hypophyseal tract connects
The posterior pituitary and the hypothalamus
104
Pituitary-Hypothalamic relationships:
Two neurohormones are
Oxytocin and ADH
105
Pituitary-Hypothalamic relationships:
neurohormones oxytocin S+E
Stim: hypothalamic neuron firing
Effect: uterine contraction, lactation, and bonding
106
Pituitary-Hypothalamic relationships:
neurohormones ADH S+E
Stim: hypothalamus neuron firing
Effect: vasopressin-kidneys conserve water (less urination), and blood vessels constrict
107
the hypothalamic hypophyseal portal system connects the
anterior pituitary and hypothalamus
108
the hypothalamic hypophyseal portal system
6 Hormones (four of which are tropic hormones) are
Growth hormone, prolactin, TSH, ACTH, FSH+LSH
109
6 Hormones (four of which are tropic hormones)
GROWTH HORMONE
S: GHRH from hypothalamus
E: Growth of muscle and bone
110
6 Hormones (four of which are tropic hormones)
PROLACTIN
S: PRH from hypothalamus
E: Milk Production
111
6 Hormones (four of which are tropic hormones)
TSH
S: TRH From hypothamus
E:TH AT THYROID
112
6 Hormones (four of which are tropic hormones)
ACTH
S: CRH from hypothalamus
E: increase cortisol secretion at adrenal gland
113
6 Hormones (four of which are tropic hormones)
FSH+LH
S: GnRH from hypothalamus
E: increase secretion of hormones and stimulate gamete production
114
The thyroid controls
Metabolism
115
The thyroid hormone is a...
S+E?
two amine hormone with iodine--- exists as T3 or T4
S: TSH from anterior pituitary
E: increase metabolic rate of the cell and so effects thermoregulation, digestion, and energy levels
116
Calcitonin....
S+E
is secreted by C cells of the thyroid, is a peptide hormone that
S: high Ca++ in blood
E: Deposit Ca++ in bone
117
parathyroid glands are primary regulators of
blood calcium
118
parathyroid glands are located on the
back of thyroid
119
Parathyroid secretes parathyroid hormone PTH
S+E
S: Low blood Ca++
E: Cause bone to free up Ca++ from bone and put it into blood
120
the adrenal glands produce hormones that are involved in
electrolyte balance and the stress response
121
the adrenal gland consists of two regions
the cortex and the medulla
122
the adrenal cortex produces
corticosteroids
123
mineralcorticoids, mostly aldosterone
S:angiotensin 2 (a hormone) and other factors
E: increase sodium retention by kidneys
124
glucocorticoids, such as cortisol
S: ATCH from the anterior pituitary
E: long term stress reponse + increase in blood glucose
125
gonadocorticoids are mostly weak.... which are converted to _ and_ in the _
adrogens, tesosterone and estrogen, tissue cells
126
the adrenal medulla synthesiszes epinephrine and norepinephrine
S: sympathetic neuron firing
E: short term stress response, including increase in heart rate, metabolic rate, and blood sugar
127
the pineal gland secretes
melatonin
128
melatonin S+E
S: hypothalamus neuron firing
E: sleepiness
129
the pancreas, gonands, and most other organs secrete
hormones
130
the pancreas is a mixed gland that secretes _ and _ gland cells
endocrine and exocrine
131
alpha pancreas cells produce.... beta cells produce....
alpha- glucagon
beta- insulin
132
glucagon S+E
S: low blood sugar
E: raise blood sugar by causing liver to convert gulcagon to lots of glucose
133
insulin S+E
S: High blood sugar
E: lower blood sugar by increasing glucose absorption in many tissues. liver forms glycogen from many glucose
134
the gonads produce
estrogen, testosterone, and progesterone
135
the ovaries (gonads) produce
estrogen and progesterone
136
the testes (gonads) produce
testosterone
137
Ovaries - Estrogen S+E
S: FSH from anterior pitutitary
E: female reproductive functions
138
Ovaries- Progesterone
S: LH from anterior pituitary
E: female reproductive funtions
139
testes- testosterone S+E
S: LH from anterior pituitary
E: male reproductive functions
140
What are the functions of blood (3)?
Transportation, regulation, protection
141
Transport functions include delivery of
and transport of
Oxygen
CO2, nutrients/ wastes, hormones
142
blood regulatory functions include maintaining
body temperature, fluid balance, pH
143
Protective function include preventing
blood loss, infection
144
Blood consists of
plasma and formed elements
145
blood is a specialized connective tissue consisting of
Plasma (extracellular), fluid, and formed elements (cells+cell fragments)
146
What are the 3 layers when blood is seperated
Erythrocytes (RBCS)
buffy coat- WBCs and platelets
plasma
147
The blood hematocrit represents the
percentage of whole blood that is RBCs
148
Physical characteristics and volume of blood
-viscous
-around 5L per person
-slightly basic (7.35-7.45 pH)
149
Blood Plasma consists of
-water (the solvent)
-solutes: electrolytes and proteins
150
components of protein in blood plasma
-clotting (e.g. fibrogen)
-antibodies- gamma globulins
-albumins: keep concentration normal
151
Formed elements of the blood are
-RBCs, Platelets, WBCs
-only WBCs have nuclei
152
Erythrocytes play a crucial role in
oxygen+CO2 transport and exchange
153
Erythrocytes (RBCs) shape+ characteristics
-Shape: disc, biconcave, large surface area
-No Nuclei, no mitochondria, no protein synthesis, no DNA
-last around 110 days
-made of membrane, Hb protein, and water
154
Erythrocytes (RBCs) shape+ characteristics
HEMOGLOBIN Characteristics
-key protein in RBCs
-made of 4 peptides together
-each peptide holds a heme group (with iron)
-Hb can hold 4 O2 molecules
155
Production of Erythrocytes: hematopoisis and its regulation
1) Stim by erythropoietin EPO hormone secreted by the kidneys when O2 is low
2) EPO stimulates red marrow where...
3) Stem cells give rise to more RBCs (Vitamin B12, folic acid, and iron are needed)
4)RBCs last around 110 days and then are removed/ recycled by the spleen
156
Erythrocyte disorders include
Anemias and polycythemia
157
Anemia is...
is caused by...
is low oxygen carying capacity
a) hemorrhage
b) low RBC production (iron deficency, lacking B12,
c) high RBC breakdown (e.g. sickle cell)
158
Polycythemia
-excess RBC production
caused by oxygen deficiency, genetic mutation, or doping
159
Role of leukocytes
defending the body
160
Leukocytes are...
WBCs
-are complete
-small number of them
-body defenses
161
Granulocytes are..
cells with stained granules in cytoplasm
NEUTROPHILLS EOSINOPHILS AND BASOPHILS
162
Neutrophills...
-make up the majority of WBCs
-attracted to sites of inflammation
-phagocytose bacteria
163
eosinophils...
-attack parasitic worms
-too many seen in allergies
164
basophills are..
-least numerous WBCs
-release histamine and heprin for inflammation
165
what are the two Agranulocytes
LYMPHOCYTES AND MONOCYTES
166
lymphocytes
-2nd most common WBCs
-T cells (thymus cells) attack infected cells
-B Cells (bone-developed) become plasma cells which make and release antibody proteins
167
Monocytes
Become macrophanges when they leave blood
168
2 Leukocyte disorders
Luekemia- cancer of WBCs
Mononucleosis- many lymphocytes develop to attack virus
169
Platelets
-are formed elements but not whole cells
-are fragments of magokaryocytes
-key role in homeostasis (stopping bleeds)
-stick to broken blood vessels; become spiky/ sticky to form a plug
170
Transfusion of whole blood is routine only when
blood loss is substantial, treating thrombocytopenia; most of the time-packed RBCs are used
171
Blood types: A/B/O groups
depend on presence or abstance of A+B proteins on RBCs (O has no protein, AB has both
172
Antibodies against foreign proteins are found where (blood)
Plasma
(e.g. if you have type-A blood you have Anti-B antibodies)
173
What is the universal donor?
Universal recipient?
O (donor)
AB (recipient)
174
RH factor is another _ protein
RBC
175
Ionotropic (direct) (fast) receptors include
For ACH (cholinergic)
nicotinic- excitirory
176
Metabotropic (indirect) (slow) receptors include
excititory or inhibitory
For ACH (choliergic)
muscarinic
For NE (adrengeric)
Alpha receptor
beta 1+2 receptor
177
ACH Receptors
muscarinic- either excitatory or inhibitory
nicotinic- excitatory
178
Norepi Receptors
Adrenergic- either excitory or inhibitory
179
Neurons that release ACH in ANS
Long pregang neuron
short postgang neuron
Short pregang neuron
180
Neurons that release NorEPI IN ANS
long postgang neuron
181
axons in parasym
long pregang axon and short postgang axon (both release ACH)
182
axons in sym
short pregang axon (releases ACH) and long postgang axon (releases NE)
183
insecticides containing organophosphatess inhibit acytylcholinesterase (which breaks down ACH) which autonomic receptors are stimulated excessivly as a result of this inhibition
Acytylcholine receptors
184
Case study:
which division of ANS has been primary affeced-
constricted pupils and low heart rate
Parasympathetic
185
Case study:
under what conditions does parasymp of ANS usually dominate
low body energy "rest and digest"
186
Case study:
What effects may the insecticide have on the GI system
increase digestion
increase diarrhea
187
Case Study: Is atropine sulfase an antagonist or agonist drug
AntagonistL Ach being inhibited so atropine is counteracting
