Exam 2-2 Flashcards

(268 cards)

1
Q

3 types of muscle

A

skeletal, cardiac, muscle

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2
Q

skeletal muscle ells

A
long
multinucleated
composed of many myofibrils
is striated--from arrangement of protein fibers in cells
voluntary contraction
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3
Q

Muscle cell life

A

born from merging of undifferentiated cells called myoblasts

once matured–no mitosis

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4
Q

Satellite cells

A

adult muscle stem cells, triggered to divide by injury– can repair some injured muscles (since muscles can’t fix themself–no mitosis)

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5
Q

hypertrophy

A

swelling of individual muscle cells– happens with exercise

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6
Q

sarcoplasmic reticulum

A

specialized endoplasmic reticulum that can sequester and store Ca.
It stores it in the ER and is will be used to spread signal throughout the muscle cell

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7
Q

T-tubules

A

invaginations of the plasma membrane that transmits the membrane depolarization into the cell

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8
Q

sarcoplasm

A

cytoplasm of a muscle cell

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9
Q

sarcoplasmic reticulum

A

endoplasmic reticulum of a muscle cell-stores Ca

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10
Q

Sarcolemma

A

the plasma membrane of a muscle cell

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11
Q

Sarcomere

A

contractile unit of a muscle cell
is the smallest functional unit of a muscle
consists of thick and thin filaments–myofilaments

1 sarcomere=z line to z line

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12
Q

Myosin

A

Thick filament
Have heads and tails– the heads are gathered and the tails are wrapped together
have 2 sites: ATP binding site and actin binding sites

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13
Q

What are the 2 sites on myosin

A
ATP site (binds and cleaves ATP-->ADP)
Actin binding site
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14
Q

thin filament

A

Actin, troponin and tropomyosin

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15
Q

Tropomyosin

A

long- string like

hides myosin binding site, preventing myosin from binding to actin

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16
Q

Troponin

A

bound to tropomyosin, binds Ca which triggers a shape change that moves typopmyosin out of the way, revealing the myosin binding site and allowing actin and myosin to interact

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17
Q

During contraction, what is in high conc. in the sarcoplasm?

A

Ca

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18
Q

Sliding filament theory

A

filaments fo not get shorter, they slide across each other, shortening the length of the cell

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19
Q

Crossbridges

A

myosin binds to actin, pulling the actin framework closer together, Z lines get closer together and H and I zones are eliminated.
Requires ATP
Happens multiple times along the actin filament
Sarcomere shortens

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20
Q

Excitation contraction

A
  1. AP reaches motor neuron terminal
  2. AP opens Ca channels, Ach is released
  3. ACh binds receptors of sarcolemma of muscle cell
  4. Na channels open
  5. Na moves in to muscle fiber causing a small local depolarization
  6. If threshold is reached– a muscle AP occurs
    Muscle AP travels along the sarcolemma and down T-Tubules
  7. AP on t-tubules excited receptors on sarcoplasmic reticulum– opening Ca channels
  8. Ca is released into sarcoplasm
  9. Ca binds troponin causing s shape change, which moves tropomyosin out of the way.
  10. Myosin binds to actin– cross bridge
  11. Cross bridge formation triggers a shape change in myosin, cocking head to an abgle, sliding the filaments past each other
  12. ADP is released from myosin head, and a new ATP binds and releases the cross bridge
  13. Myosin binds to next available actin binding site
  14. ATP breaks down to ADP, energy is transfered to myosin head, cocks again and the filaments slide
  15. continues as long as intracellular Ca is high, and ATP is available
  16. In synapse- AChE is degradding ACh
  17. Chem gated Na channels close
  18. Ca pump in sarcoplasmic reticulum re-sequesters Ca
  19. Removal of Ca from troponin restores blocking of actins binding sites
  20. Cross bridge cycling stops, relaxation occurs
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21
Q

In muscles– do we use intra or extracellular Ca?

A

Intra cellular, while in normal AP in neurons we use extracellular Ca

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22
Q

What is ATPs role in filament binding?

A

ATP binds and releases the crossbridge.

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23
Q

Muscle motor units

A

functionally all the same– can’t contract q/o the others.

Helps control how much of a msucle you need to use– done by fine tuning the number of motor units

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24
Q

Neuromuscular junction overview

A

Only one NT: ACh
One form of NT clearance: AChE
Only excitatory

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25
twitch
A response of a single muscle fiber to a single AP
26
latent period
can be different for different muscle fibers depend on speed of Ca pump Slow pump--> Ca stays longer->twitch lasts longer Fast pump-->Ca removed faster--?twitch ends quickly
27
isotonic contraction
muscle contracts and creates enough force to move a load--> like lifting your keyys Initiate as isometric contraction until the tension matches the load
28
Isometeri contraction
When you can't move the load. Like pushing a wall thats not going to move no matter how hard you push
29
ATP is muscle contraction
1. ADP-->ATP by creatine phosphate 2. Oxidative phosphorylation of ADP in the mitochondria 3. ADP-->ARP by anaerobic glycolysis in cytosol
30
Creatine phosphate
builds up in muscle At start of contraction, CP can phosphorylate ADP to make ATP Conversion is so fast that during intiial contraction, ATP rates barely change, while CP levels drop (aka ATP is being made as fast as its being used)
31
Oxidative phosphorylation/glycolysis for ATP
Glycolysis-- 2 ATP/glucose OP-36 ATP/glucose-- needs O2 Both are slower than CP mediated ADP, OP is slower than glycolysis
32
myoglobin
can store oxygen for muscles
33
How long does glycogen storage last?What happens when you run out?
lasts for 5-10 minutes. After that circularory system must meet demands. Glycogen sfrom liver is broken down, adter 40 minutes, fatty acids begin to be broken down
34
Central fatigue
your CNS tells you to stop-- deelings of tiredness, psychological factors
35
Peripheral fatigue
factors within muscle cells tell you to stop | includes conduction problems and lactic acid build up, inhibition of cross bridge formation
36
Conduction problems
K+ builds up in the t-tubules, no K+ gradient, no repolarization
37
Lactic acid buildup
lactic acid results from anaerobic glycolysis. It does not effect contractile proteins, but can slow re-sequestration of Ca, leading to prolonged contraction
38
Inhibition of cross bridge formation
an excess of ADP and Pi may inhibit formation od new cross bridges.Impaired full contraction and impaired relaxation may result.
39
How are skeletal muscle fibers classified?
Cross bridge cycling speed, based on ATPase on myosin | How they get most of their ATP, oxidative phosphorylation of anaerobic glycolysis
40
Fast v. Slow fibers
fast fiber cross bridge formation occurs 4X faster than slow fiber force produced is the same depends on ATPase
41
Oxidative Fibers
get ATP from oxidative phosphorylation--much more efficient Requires lots of mitochondria Myoglobin is the oxygen source referred to as red fibers
42
Glycolytic Fibers
Gets ATP from glycolysis- less efficient, need more glucose, less oxygen -few blood vessels -few mitochondria -much higher glycogen stores-- since each glucose only gives 2 ATP WHITE FIBERS
43
Type 1 Muscle
Slow oxidative | -low myosin ATPase, high oxidative capacity
44
Type IIa muscle
Fast oxidative glycolytic | high myosin ATPase, high oxidative capacity, intermediate glycolytic capacity
45
Type IIb
Fast glycolytic | high myosin ATPas, high glycolytic capacity
46
If looking at a dead body, with no ATP where will Ca be found?
In sarcoplasm, muscles will be contracted myosin can't unbind from actin without binding a new ATP
47
If you block ACh in the NMJ what happens?
The cell would never have a graded potential
48
Slow oxidative fibers and fatigue
Slow use of ATP, can generate ATP Doesn't fatigue easily. Used in muscles that are always on, back legs etc
49
Fast oxidative fibers and fatigue
Lasts a a while, then fatgues | fast ATP- can contract faster legs
50
Fast glycolytic fibers and fatigue
fast use of ATP minimal ability to replenish ATP, fatigues quickly. In fingers and hands
51
Motor units
all the same fiber type, controled by one motor neuron. | Proportions of motor units vary based on need
52
Plasticity of skeletal muscle
- fiber type - mitochondrial concentration - capacity for glycogen storage - local capillary concentration - myoglobin concentration - size of muscle cell - concentration of actin and myosin microfilaments - neural pathways These changes can be gained OR lost
53
Soreness
exercising beyond capacity - damage to muscles triggers inflammatory response - lengthening muscle (going down stairs, lowering weights slowly) produces more soreness NOT DUE TO LACTIC ACID BUILD UP
54
Cramps
persistent, high frequency AP Elecytrolyte imbalance Caused by overexercise, persistant dehydration
55
Changes with endurance exercise
Increased mitochondria increase in capillary network feeding the muscles slight decrease in fiber diameter and maximal strength also leads to associated changes in the cardiovascular and repiratory system
56
Changes with strength exercise
Primarily affects fast twitch fibers--increase in diameter, increased synthesis of actin and myosin, increase in enzymes in glycolysis pathway. Gain strength, but not endurance-- fatigue rapidly Sometimes fains in strength without gains in size
57
Poliomyelitis
Polio A virus that infects motor neurons 90% of cases have no symptoms, 10% milkd disease, 1% paralysis
58
Muscular dystrophy
Genetic or autoimmune defects in costamere protein. | Progressive weakness, inability to walk by age 12 Death by 20-25
59
Atrophy
Use it or lose it | Muscle cell loss by decrease in nerve use, or decreased muscle use
60
Myasthenia gravis
Autoimmune activity against ACh receptors, muscle fatigue and weakness Therapies: AChE inhibitors, autoimmune drugs, removal of antibodies from plasma
61
Smooth muscle
no banding pattern NO TROPONIN innervation comes from autonomic-- not voluntary spindle shaped contract as a sheet uni-nuclear-- can undergo mitosis and repair in gut, uterus, blood vessels and pulmonary
62
Role of Ca in smooth muscl
CA binds to and activates calmodulin Ca-calmodulin activates a kinase The kinase phosphorylates myosin, activating it Myosin binds actin and cross bridge cycling occures as long as Ca is entering the cell, the contraction will occur.
63
Sources of Ca for smooth muscle
Can come from sarcoplasmic reticulum (inracellular) and from extracellular fluid Smooth muscle cells have voltage gated and chemically gatedCa There is NO ROLE for Na in smooth muscle contracition Amount of Ca=amount of contraction
64
Removal of Ca in smooth muscle
removed by ATP dependent pumps | rate is very slow (3+ sec. compared to <1 sec. for skeletal muscle)
65
Smooth muscle gradation and tone
Ca channels only let in enough Ca to activate a portion of the cross bridges more stimulus=stronger contraction Can alter how much cystolic Ca is kept inside to maintain tone-- helpful with always on muscles, like sphincters
66
The role of stretch in smooth muscle
Stretch does not effect force possible. Stretch can increase contraction because stretch can open mechanically gated ion channels
67
What do smooth muscle cells contract in response to?
autonomic inputs can be excitatory or inhibitory - in response to depolarization from a neuron - spontaneously - spontaneously depolarize and contract without nueronal input-- waves
68
Pacemaker cells
the tendancy to spontaneously depolarize at regular intervals. Some smooth muscle cells work this way for regular contraction-- like GI tract
69
Varicosities
string of NT filled bumbs of autonomic axons
70
Factors that indfluence smooth muscle cells
``` Hormones --ex. hormonal control over utering contraction --ex. epinepherine and gut motility Paracrine signalling Acidity O2 availability Extracellular ion composition ```
71
Single unit smooth muscle
gap junctions link the cells, many cells contract as a sheet stretching often induces contraction ex. GI tract(full stomach=contraction), Uterus (braxton hicks), arterioles(high BP)
72
Multiunit smooth muscle
each cell responds on its own, no gap junctions | ex. Arteries, pulmonary system, haid associated muscle
73
Cardiac Muscle
- striated - troponin AND tropomyosin - T-tubules and SR - single nucleated cells, forked - specialized fused ends called intercalated disks
74
intercalated discs
in cardiac muscle make stronger, and have gap junctions to quickly pass a contraction So when one depolarizes, they all depolarize
75
Desmosomes
join cells tightly-- at intercalated discs
76
Gap junctions
allow cytoplasmic flow of ions. So when one cell depolarizes, they all depolarize
77
Contraction in Cardiac muscle
-involves Ca and Na channels Na channels provide initial depolarizeion (graded potential) Voltage gated Ca channels open and Ca flows into the cell. ---these are called L-type channels, long lasting depolarization- elongates refractory period Ca floods cytosol from SR and extracellular fluid once in it binds to troponin and works the same way as skeletal muscle. Ca pump redurns Ca to SR and exracellular fluid
78
Initiation of depolarization in cardiac muscle
Specialized cardiac muscle cells have pacemaker potential These exist at only 2 plasces in the heard Wave of depolarization spreads down through conducting fibers throughout the heard
79
Does skeletal muscle have striations?
yes
80
does cardiac muscle have striations?
yes
81
does smooth muscle have striations?
no
82
Does skeletal muscle have thick and thin filaments?
yes
83
Does cardiac muscle have thick and thin filaments?
yes
84
Does smooth muscle have thick and thin filaments?
yes
85
Is skeletal muscle control voluntary or involuntary?
voluntary
86
Is cardiac muscle control voluntary or involuntary?
involuntary
87
Is smoothmuscle control voluntary or involuntary?
involuntary
88
What shape are skeletal muscles cells
long and cylindrical
89
What shapre are cardiac muscle cells?
short and chubby
90
What shape are smooth muscle cells?
Spindle
91
Are skeletal muscle cells uni or multi nucleated?
multi
92
Are cardiac muscle cells uni or multi nucleated?
uni
93
Are smooth muscle cells uni or multi nucleated?
uni
94
What is the source of Ca for skeletal muscle?
Intracellular
95
What is the source of Ca for cardiac muscle?
intra and extracellular
96
What is the source of Ca for smooth muscle?
intra and extracellular
97
What is the site of Ca regulation in skeletal muscle?
troponin
98
What is the site of Ca regulation in cardiac muscle?
troponin
99
What is the site of Ca regulation in smooth muscle?
Myosin
100
What is the refractory period duration for skeletal muscle?
very short
101
What is the refractory period duration for cardiac muscle?
very long
102
What is the refractory period duration for smooth muscle?
short
103
What is the contraction control for skeletal muscle?
only somatic motor neurons
104
What is the contraction control for cardiacmuscle?
innervation, autorhythmc, endocrine
105
What is the contraction control for smooth muscle?
innervation, autorhythmic, endocrine
106
What is the effect of K+ channel blocker on NMJ?
Lots of ACh in the synapse
107
What happens if you leave ACh in the synapse?
Prolonged muscle contraction
108
What would adding an Ach antagonist to NMJ do?
no muscle contraction
109
Which type of muscle uses calmodulin?
Smooth
110
Tropic hormones
stimulate other glands to make and release hormones. Usually also trigger growth of the target gland
111
Hormone synthesis
most hormones are built in the cell as large inactive molecules They are stored in their inactivated state and can be activated before release or activated in the blood or at the target tissue
112
In what ways can endocrine gands be stimulated to release a hormone?
1. Monitor blood and release the hormone in response to a change 2. Neuron stimulates the release of the hormone 3. Controlled by a tropic hormone.
113
Humoral stimulus
When a hormone is released in response to a change in the blood.. Ex. insulin and glucose changes
114
hormones and allosteric inhibition
the presence of a hormone can inhibit the step of a pathway by acting as an allosteric nhibitor of an enzyme. This will turn off a pathway resulting in negative feedback
115
GnRH/testosterone feedback loop
GnRH-->LH--> testosterone. Testosterone then inhibits the release of more GnRH
116
Amines
derived from amino acids help build thyroid hormones, epinephrine and norepinephrine Are water soluble, so need transport into cells
117
Peptide hormones
larger than amine hormones built from polypeptides the majority of hormones are peptide hormones they are typically water soluble, need transport into the cell
118
steroid hormones
lipid based, built from cholesterol ex. corisol, aldosterone, tersosterone, estradiol, vitamin D Are hydrophomic, so need plasma protein transporters, but easily diffure in and out of cells
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Hyposecretion
When not enough hormone is secreted
120
Hypersecretion
too much hormone released
121
Hyporesponsiveness
not enough reception by target cells | Ex. type 2 diabetes
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Hyperresponsiveness
More reception by target cells
123
Primary hyposecretion
- damage to gland=less hormone - enzyme deficiency=less hormone - dietary deficiency of iodine=less hormone produced
124
Secondary hyposecretion
too little tropic hormone produced/released. Results in reduction of hormone secretion
125
Primary hypersecretion
Endocrine cell tumor=produces hormone out of control
126
Secondary hypersecretion
excressive stimulation by tropic hormones
127
Roles of the hypothalamus
1. influences hormone secretion activity of the anterior pituitary-- with tropic hormones 2. Produces hormones itself 3. Oversees hormone secretion by the adrenal medulla
128
Anterior pituitary
hormone secretion from this is influenced by tropic hormones from the hypothalamus releases 6 hormones is regulated through secretion of hypophysiotropic hormones into the hypothalamo-pituitary portal system
129
posterior pituitary
stores hypothalamic hormones, then releases them into the local capillary network
130
Hypothalamus releases corticotropin releasing hormone (CRH)...
triggers release of adrenocoticotropic hormone from the anterior pituitary (ACTH)
131
Hypothalamus releases Growth hormone releasing hormone (GHRH)
which releases growth hormone (GH) from the anterior pituitary
132
Hypothalamus releases thyrotropin releasing hormone (TRH)
which releases thyroid stimulating hormone from the anterior pituitary
133
Hypothalamus releases gonadotropin releasing hormone (GnRH)
which releases Luteinizing hormone (LH) and follicle stimulatin hormone (FSH) from the anterior pituitary
134
Hypothalamus releases somatostatin (SS)
which INHIBITS the release of GH from anterior pituitary
135
,Hypothalamus releases dopamine (DA)
which inhibits the release of prolactin from the anterior pituitary
136
Thyroid stimualting hormone
anterior pituitary hormone Is tropic Stimulates the release of thyroid hormone from the thyroid gland
137
Prolactin
is an anterior pituitary hormone | regulates breast milk production, and is anti-libido released during stress
138
Adreocorticotropic hormone
is an anterior pituitary hormone | Stimulates the adrenal cortex to produce cortisol
139
Growth hormone
is an anterior pituitary hormone | Causes the growth of bones, muscles and most body cells
140
Follicle stimulating hormone and luteinizing hormone
anterior pituitary proteins | influence reproductive stuff by regulating hormone synthesis by the gonads
141
What regulates the hypothalamus?
CNS stimulation- stress, environmental influences, NT | Hormone levels in the blood
142
Oxytocin
Posterior pituitary hormone positive feedback loop for cervical opening in labor and milk let-down in lactation. plays a role in bonding an social stuff
143
Vasopressin
posterior pituitary protein aka antidiuretic hormone constricts smooth muscle cells around blood vessls, increasing blood vessels, increasing blood pressure and decreasing urine output
144
Thyroid gland
butterfly shaped gland in neck | secretes 2 hormones: Thyroid hormone and calcitonin
145
Thyroid hormone
released by thyroid gland maintains metabolism/body temperature iodine is an important part of TH production There are 2 versions of TH: T4 and T3 (based on # of iodine molecules Production and secretion is regulated by TSH`
146
TH production
TRH (hypothalamus)-->TSH (ant. pit.) --> TH (thyroid gland TH then negative inhibits TSH and TRH
147
Hypothyroidism
low metabolic rate, weight gain, lethargy, feeling cold Happens because
148
Goiter
due to low iodine in diet, thyroid can't produce enough TH, but pituitary continues to make TSH
149
Action of thyroid hormone
- increase carb intake from intestine and fatty acid release by horone=more fuel in blood stream - increase activity of Na/K pumps=increase use of calories and increase of heat
150
Symptoms of hypothyroidism
``` decrease in overall metabolism cold intolerance weight gain fatigue loss of concentration ```
151
Symptomes of hyperthyroidsim
``` overall metabolism increases heat tolerance weight loss twitchiness anxiety ```
152
Calcitonin
produced by thyroid glad encourages calcium deposition into bone from blood "calcium to the bone" release is controlled by blood Ca levels
153
parathyroid hormone
``` released by parathyroid encourages less calcium to be deposited in blood stimulated formation of vt. D opposes the action of calcitonin regulated directly by blood Ca levels ```
154
Viamine
organic compound present in minute amounts in the diet that are essential to metabolism
155
Vit. D3
formed by action of UV light on a cholesterol molecules in the skin
156
Vit. D2
derived from plants
157
Vit. D function
targets the small intestine increases uptake of Ca Parathyroid hormone increases synthesis is the most common deficiency in the US. plays a role in reducing inflammation
158
Vitamin D and TB
vit. d helps to speed the recovery of TB patients, reducing markers of inflammation increase in sun, decrease of TB symptoms.
159
Roles of Ca in the body
``` important in signalling pathways muscle function NT release BONES cardiac and smooth muscle function ```
160
Bones
rebuild 20% of our skeleto each year is a type of connective tissue Is a collagen matrix upon which calcium salts are deposited Works as a bank-calcium is deposited and withdrawn as needed growing bones contain cartilage connective tissue
161
epipheyseal growth plate
proliferating cartilage | bones can't grow, cartilage at growth plates grow, then becomes bone
162
Osetoprogenitor cells
stem cells that become osteoblasts
163
osteoblasts
become new bone
164
osteocytes
mature bone cells in matrix
165
Osteoclasts
large multinuclearclls that eat/reabsorb bone
166
Bone growth
chondroblasts in epiphyseal plate generate new cartilage | osteoblasts at the shaft of the plate convert cartilage to bone
167
Growth rate
childre undergo 2 periods of intense growth before 2 years, and during puberty boys enter puberty 2 years later than girls, during puberty boys grow more due to the action of testosterone
168
factors that limit growth
persistent disease lack of AA, fatty acids, vitamins, minerals Physical or psychological stress
169
Growth hormone
stimulates maturation and mitosis of chondrocytes | elongates epiphyseal plates, more material for bone conversion
170
acromegaly
growth after plates fuse---just cartilage grows
171
IGF
insulin like growth factors secreted by liver and osteoprogenitor cells triggered by GH autocrine, paracrin and hormonal functions to dive the mitosis of chondrocytes
172
Growth hormone stimuli
only secreted during exercise and 1-2 hours after sleep begins
173
Sex hormones and growth
At low levels: promote growth by increasing GH and IGF1 | At high levels: promote ossification directly, cause ossification of epiphyseal plates
174
Testosterone
``` is an anaboilc steroid used to increase protein synthesis in muscles Side effects: liver damage prostate cancer infertility aggression ```
175
Cortisol
Antigrowth inhibits DNA synthesis and bone growth Use of cortisol in children to precent/treat asthma etc can temporarily stunt growth-- have to take breaks to alow growth catch up
176
Stress and bone formation
high levels of cortisol (released when stressed) can temporarily hault growth
177
Gametes
cells that fuse with other cells to make an embryo
178
gametogenesis
making gametes
179
gonads
organs that produce gametes
180
Male reproductive goals
make gametes, get them to the egg
181
Female reproductive goals
make gametes, prepare place to receive gametes, prepare place to house the developing embryo, get give birth, feed offspring
182
leydig cells
in testes, secrete testosterone
183
sertoli cells
aid in spermatogenesis in semineferous tubules filter nutrients for developing sperm bind testosterone and transport it into the lumen is triggered by FSH, make prosperm paracrine signaling molecules which help sperm mature
184
seminiferous tubules
``` unbroke ring of sertoli cells make blood-testes barrier sperm stem cells at periphery developing cells b/w sertoli cells are locked into place by tight junctions fully differentiated sperm at the lumen ```
185
how many sperm released in 1 ejaculation?
30-300 million
186
Items required for success of sperm
speed, envionmental conditions, direction, adequate digestion of egg coat
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acrosome
on head of sperm. has enzyme that digests the coating of eggs
188
How does the egg prevent multiple sperm from entering?
once a sperm gets in , there is an exocytosis of the corticol granuales, the contents are released the the zona pellucida hardens so nothing else can pentrate it
189
testosterone functions
required for spermatogenesis development and maintainance of male reproductive organs required for maintenance of male secondary sex characteristics opposes action ot estrogen on breat development sex drive muscle growth
190
what impact does endogenous testosterone have?
decrease in GnRH, LH and testosterone
191
production of testosteron
endocrine cells in testes have enzymes to convert: Cholesterol-->androstenedione-->testosterone androstenedione- is also found in the adrenal cortex small amounts of testosterone are converted to estradiol
192
aromatase
converts testosterone to estradiol
193
semen
combination of sperm and secretions from accessory glands takes 2 weeks to prepare lives 48-72 hours once in the female reproductive tract
194
testosterone decline
occurs around age 40 | slow and steady decline
195
Ovaries
make gametes
196
uterus
houses the fetus
197
fallopian tubes
transports egg to uterus, site of fertilization
198
vagina
entrance/exit to system
199
cervix
"doorway" from vagina to uterus
200
Gamete production
produce oocytes in the ovary during the fetal period oocytes are encased in follicles each month a few follicles mature, the one that matures the fastest is the one that releases the egg
201
ovulation
when the egg is released from the follivle and availabel for fertilization
202
corpus luteum
what the follicle is called after ovulation when it remains in the ovary (light body) , if pregnancy does not occur it dies and triggers menstruation is an active endocrine gland- makes progesterone
203
perimetrium
outer membrane of uterus
204
myometrium
thick smooth muscle layer of uterus-- is most powerful muscle in the body
205
endometrium
lining of the uterus composed of thick connective tissue, which is sloughed off and regrown every 28 days in menstruation
206
Preparing for pregnancy
1. First half of ccyle: maturing an egg 2. ovulation 3. enriching uterine lining for implantation 4. shedding lining if implantationdoes not occueqw
207
which cells release estrogen?
granulosa cells
208
what releases progesterone?
a small amount is made by theca cells, most is made by he corpus luteum can also be made by the adrenal cortex
209
Progesterone synthesis location
made by corpus luteum and placenta in women, and in the adrenal cortex
210
progesterone functions
maintain uterine lining , water and ion balance, regulation of synaptic activity associated with mood, memory and immune functions, promotes schwann cells,
211
Progesterone and MS
progesterone promotes schwaan cells, so is helpful in relieving symptoms of MS
212
what triggers ovulation?
a surge in LH (which is released by anterior pituitary and controlled by estrogen levels)
213
What do birth control pills do with regard to LH
prevent the surge in LH this preventing ovulation
214
what triggers LH surge?
estrogen peak
215
what role does estrogen have in menstruation?
triggers LH secretion, builds endometrium and prepares for pregnancy
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what role does progesterone have in menstruation/pregnancy?
progesterone prevents the shedding of the lining menstruation occures when progesterone levels fall
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how does progesterone based birth control pills work?
it inhibits LH surge
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Basic role of FSH in female reproduction
stimulates development of follicles. | There is no role for this in the luteal phase
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basic role of LH in female reproduction
triggers ovulation | There is no role for this in the luteal phase
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basic role of estrogen in female reproduction
prepares uterine lining, breasts for lactation SURGE IN ESTROGEN TRIGGERS THE LH SECRETION
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basic role of progesterone in female reproduction
maintains uterine lining. Theres is no role for this in the follicular phase
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How does the body make sure we only have one baby at a time?
Follicular phase and ovulation hormones are inhibited by the corpeus luteum progesterone inhibits LH and GnRH
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Mestruation
Corpeus lutum degrades--> decrease in estrogen and progesterone-->prostoglandin secreting in endometrium-->vasoconstriction and uterine contractions= menstruation
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prostoglandins
triggers vasoconstriction and uterine contractions, released due to decrease in estrogen and progesterone. Redues blood flow, causing endometrial tissue to die. and contractions trigger sloughing
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In vitro
grow blastocyte in test tube, then implant it into uterine lining
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fraternal twins
one egg ovulates from each ovary
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Fertilization
occurs in fallopian tube egg divides and develops as it travels to the uterus if endometrium is primed, it implants and begins to grow.
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tend and befriend
release oxytocin during stress events
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oxytocin
promotes the resolution of stress by activating parasympathetic system promotes bonding and social behavior during stress response to keep track to offspring and find friends
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male hormanal profile during stress
epinephrine, corisol and testosterone
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female hormonal profile during stress
epinephrine, cortisol and oxytocin
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Needs in a stress situation
O2, blood to muscles, glucose
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What physiologically changes in a stress event
Increase: breathing, hear rate, shift blood flow to skeletal muscles, mobilize glycogen, protein breakdown Decrease: urine output, shift blood aaway from digestion, decrease inflammation and immunity, decease sex drive, decrease bone growth
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Stress
real or perceived threats to our homeostasis
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adrenal glands
pyramid shaped glands above the kidnesy--is the major stress gland Release aldosterone, cortisol, androgens and epinepherine
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Adrenal cortex
makes over 25 lipid based steroid hormones-- the corticosteroids (SALT, SUGAR, SEX)
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mineralocorticoids
released by adrenal cortex, are lipid based regulate minerals/electrolytes (water salt balance) released by the outer layers
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glucocorticoids
released by middle section of adrenalcortex regulate glucose levels in blood lipid based
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gonadocorticoids
regulate gonadal hormones (androgens) made by inner section of adrenal cortex lipid based
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Epinephrine
dialiates airways to increase breathing rate breakdown glycogen in liver/skeletal muscles, and breakdown fat in adipose tissues shifts vlood away from digestive system-- decreases the need to eat
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Cortisol
``` Shifts bloodflow to skeletal muscles breakdown protein in bone and skeletal muscles and breakdown fat in adipose tissue turs everything off. decreases growth of immune system increases appetite to replenish stores increase prolactin to decrease sex drive breakdowns bone increases growth hormone (in order to break down protein) ```
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Hyporthalamic pituitary adrenal axis
Hypothalmus releases CRH-->ant. pit. releases ACTH-->Adrenal cortex releases cortisol cortisol has negative feedback on the other two
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Stress and eating acute stress
Epi decreases the need to eat (ex. fen phen )
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Stress and eating chronic stress
Cortisol increases the need to eat | to replenish energy storage.
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Chronic stress and cardiovascular system
cort. causus systemic vasoconstriction and an increase in blood pressure
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Chronic stress and immune system
Cort. decresases cytokine cross talk and decreases the immune cells, means system is vulnerabel and have increased risk of infection
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need more glucose
decrease insulin, increase glucagon
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decrease need to respond to injury
increase beta-endorphin-- is a pain killer
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decrease need to grow
decrease GH
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decrease need to pee
increase ADH, increase blood volume-- in case of hemmorrhaging
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decrease need to have sex
increase prolactin decrese sex drive decrease gonadal hormones decrease fertility
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Benefits of cortisol
-circadian rhythm -maintain BP --permissive for epi -maintain glucose metabolism brake on the immune system
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Hyposecretion:Adrenal insufficiency | Causes
decreased cort. decreased adrenal developmet decreased enzyme synthesis damage (addisons disease)
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need more glucose
decrease insulin, increase glucagon
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decrease need to respond to injury
increase beta-endorphin-- is a pain killer
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decrease need to grow
decrease GH
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decrease need to pee
increase ADH, increase blood volume-- in case of hemmorrhaging
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decrease need to have sex
increase prolactin decrese sex drive decrease gonadal hormones decrease fertility
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Benefits of cortisol
-circadian rhythm -maintain BP --permissive for epi -maintain glucose metabolism brake on the immune system
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Hyposecretion:Adrenal insufficiency | Causes
decreased cort. decreased adrenal developmet decreased enzyme synthesis damage (addisons disease)
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Hyposecretion:Adrenal insufficiency | Symptoms
weakness,fatigue decreased appetite and weight decrease blood presure, decreased glucose increase skin pigmentation (ACTH in blood is a precursor to melotoin
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Hyposecretion:Adrenal insufficiency | Treatment
Hydrocortisone or prendisone for life
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Hypersecretion: Cushing syndrome | Causes
``` exogenous therapies, increased cort adrenal tumors (increased cort) pituitary tumors (increased ACTH and cort) ```
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Hypersecretion: Cushing syndrome | symptoms
``` osteoporosis decreased muscle mass odd body fat distribution hypertension hyperglycemia immunosuppression ```
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Hypersecretion: Cushing syndrome | Treatment
stop exogenous therapy | surgery
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prolonged heavy exercise
``` increase epi and cort decrease insulin, increase glucagon increase aldosterone and ADH increase endorphins increase prolactin ```
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Fasting
increases epi and cort decrease insulin, increase glucagon increase aldosterone and ADH
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Are neuromuscular junctions inhibitory?
No. Only excitatory