Lecture midterm #2 Flashcards
1
Q
What is blood pressure?
A
The pressure on the walls of the blood vessels
2
Q
What is systolic pressure?
A
The “Peak” of the arterial BP. During ventricular systole
3
Q
What is diastolic pressure?
A
“Minimum” arterial BP. At the end of ventricular diastole.
4
Q
Where is Blood Pressure usually measured?
A
Brachial artery (inside elbow)
5
Q
Where is blood pressure the highest in the body?
A
Arteries that are closest to the heart.
6
Q
Where is blood pressure slow in the body?
A
In capillaries and veins
7
Q
What is MAP?
A
(Mean arterial pressure) - diastolic pressure + (Pulse pressure/3)
8
Q
What is pulse pressure?
A
Difference between systolic and diastolic pressure.
9
Q
What is Hydrostatic pressure?
A
-Forces “pushes” water OUT of a solution
- Water is being “pushed” away from an area of higher hydrostatic concentration to an area of lower hydrostatic pressure.
10
Q
Name some local vasodilators.
A
CO2 (due to increase in aerobic metabolism)
Lactic acid (due to increase in anaerobic metabolism)
which will…
lower pH (more acidic)
increase temperature
This is all due to increased cellular activity locally
Histamines
Nitric oxide
11
Q
Name some local vasoconstriction
A
Thromboxanes
12
Q
What is ANP?
A
atrial Natriuretic peptide
13
Q
What is EPO?
A
Erythropoietin
14
Q
What is ADH
A
antidiuretci hormone (aka vasopressin)
15
Q
What is RAAS?
A
Renin-angiotensin-aldosterone-system.
16
Q
Main function of the respiratory system?
A
Provide SURFACE AREA for gas exchange (between air and circulating blood)
VENTILATION move air into and out of the lungs.
PRODUCE sounds for communication.
PROTECT respiratory surfaces from pathogens,temp, other stuff
17
Q
What is the respiratory tract split into (physically)?
A
Upper and Lower respiratory tract.
Upper = nose, nasal cavity, paranasal sinuses, pharynx.
Lower = larynx, trachea, bronchi, bronchioles and alveoli.
18
Q
What is the respiratory tract split into (functionally)?
A
Conducting Division
Respiratory Division
19
Q
What type of epithelium makes up the alveoli?
A
Simple squamous
Below is the basement membrane. (0.1um-0.5um)
20
Q
What are alveolar macrophages?
A
Cleanup crew
21
Q
What are type II alveolar cells?
A
Produce Surfactant
22
Q
Which way will air flow in the lungs?
A
From an area of high pressure to an area of low pressure (it is directly proportional to the pressure gradient and inversely proportional to resistance).
23
Q
Is inhalation an Active process?
A
Yes! Muscles contract, increasing the volume of the chest cavity and creates a partial vacuum to pull air in.
24
Q
Is exhalation a passive process?
A
Usually, but it can be active. Muscles relax decreasing volume of the chest cavity pulling air out of the lungs.
25
What is the first Gas Law?
Boyles’s Law: P=1/V
Pressure (P) is inversely proportional to volume (V)
Gas will flow from an area of higher pressure to lower pressure. (Imagine a piston)
26
How do you decrease pressure in the lungs?
You increase the volume. DO THIS by
- Contraction of the diaphragm
- Superior movement of the rib cage (using contractions of the intercostals)
- Results in inhalation because the pressure in the lungs is lower than the pressure in the atmosphere.
27
What are the accessory muscles used for inspiration (contract only during forceful inspiration)?
Sternocleidomastoid
Scalenus
28
Whatis "Quiet breathing" called?
Eupnea
*inhalation is active, exhalation is passive
(intra-alveolar pressure)
29
What is "Forced breathing" called?
Hyperpnea
*inhalation and exhalation are both active
**uses "accessory muscles" for this
(intra-alveolar pressure)
30
What is meant by “greater compliance”?
Easier to fill and empty lungs.
31
What is Surfactant? What makes it?
-An oily substance used to “grease” up the lungs.
-Produced by the greater alveolar cells (Type II alveolar cells).
- Amphipathic (polar and non polar)
(Used to reduce surface tension of water on the alveoli)
32
Describe the Hydrophobic and hydrophilic parts of Surfactant.
Hydrophilic part interacts with the layer of water
The hydrophobic part makes a “coating” on top to reduce surface tension and prevent collapse of alveoli.
33
Why are the surface of each alveolus covered by water?
Keep the surface moist for gas exchange however since water is attracted to each other this could cause the alveolus to collapse. Hence why we need surfactant.
34
What is Tidal volume?
Amount of air moved in or out of the lungs during one respiratory cycle (during quiet breathing)
Average 500ml at rest
35
What is meant by respiratory rate?
Breaths per minute.
36
Average Breathes Per minute for an adult?
12 to 18 breaths per minute
37
What is IRV?
"Inspiratory Reserve Volume"
Amount of air youre able to take in, on top of your tidal volume.
males = 3300 mL
Females = 1900 mL
38
How to measure your total inspiratory capactiy?
IRV + tidal volume
39
What is ERV?
"Expiratory Reserve Volume"
Amount of air youre able to expel (voluntaryily)
= 1000 mL
40
For the IRV and ERV, what must be used to more more air out of the lungs during Forced breathing?
Use Accessory muscles to actively move more air out of the lungs.
41
How much air is left in the lungs of males even after a forced exchale?
1200 mL
42
How much air is left in the lungs of females even after a forced exhale?
1100 mL
43
What is Vital Capacity?
The maximum amount of air that can move in or out of lungs in one respiratory cycle.
ERV + tidal volume + IRV = Vital capacity
44
What is the vital capacity in males?
4800 mL
45
What is the vital capacity in females?
3400 mL
46
What is the TOTAL lung capacity?
Total volume of the lungs.
Vital capacity + residual volume
47
What is the total lung capacity in males?
6000 mL
48
What is the total lung capacity in females?
4500 mL
49
What is FEV?
Forced Expiratory Volume.
Amount of air that can be forcible expelled.
The amount expiered in the first second = FEV1
50
What are some things to think of for "gasses diffusing across membranes"?
-Concentration differences (gradients)
- Temp. high temp = faster diffusion
- Thickness of membrane (distance to diffuse).
shorter distance = more efficient/faster diffusion.
- "Gas laws". Dalton's law of partial pressures
Henry's law of gas solubilities
51
What is "Dalton's Law" (partial pressures)?
Air is made up of N2, O2, H2O and CO2 and all of those elements have their own pressures that contribute to the TOTAL PRESSURE.
(eg) N2 is 78.6% of air. so partial pressure is 78.6% of the total air pressure.
P N2 + P O2 +P H2O + P CO2 = 760mmHg
52
Why do the lungs move with the diaphragm and ribs?
A thin film of serous fluid in the pleural cavity.
Intrapleural pressure = negative pressure. That holds the 2 membrane together.
53
What is Intrapleural pressure?
The pressure within the pleural cavity.
The pressure in the space of the parietal and visceral pleurae.
(-4mmHg) at average (-18mmHg) during powerful inhalation
54
What is Intr-alveoloar pressure?
aka intrapulmonary pressure
The pressure inside the alveoli of the lungs.
(quiet and forced breathing)
55
Resistance to airflow: Bronchoconstriction
- Increased resistance to airflow
- Caused by contractions of the smooth muscle due to stimulation from the Parasympathetic NS OR allergic reactions Or low concentrations of CO2 (local control)
- Diameter of the bronchioles decreases (increases resistance)
56
Resistance to airflow: Bronchodialation
- Decreased resistance to airflow
- Diameter of bronchioles increases (less resistance)
- Cased by sympathetic NS (epinephrine) or high concentrations of CO2 (local control)
57
Resistance to airflow: Pulmonary compliance
How easily the lungs can expand or contract.
"greater compliance"= lungs are easier to fill or empty.
"reduced compliance" (stiff lungs) = lungs cant fill as easy as they should
- caused by change in connective tissue (scar tissue), mobility of thoracic cage (arthritis) or lack of surfactant
58
Why are alveoli covered in surfactant?
They are covered in water to keep them moist of gas exchange but because of cohesion (water sticking to water) they could cause the alveoli to collapse.
Surfactant prevents this- Amphipathic (polar and non polar)
(Used to reduce surface tension of water on the alveoli)
59
What is Residual volume?
Amount of air in lungs even after forced exhalation. After ERV
60
What is Henry's Law?
(Relationship between solubility and pressure)
Amount of gas in a solution is directly porportional to the partial pressure of that gas.
(higher amount of partial pressure of gas = higher amount of gas in that solution)
61
How and why does O2 cross the respiratory membrane?
- Alveoli have a huge surface area and a very shot distance to the blood supply below (little ditance means quicker diffusion)
- O2 is lipid soluable so its easy to pass through the surfactant and the cell membrane
- Significant difference in pressure (higher in alveoli (air), lower in capillary (blood)
62
tell me about the exchange of CO2 across the respiratory membrane.
(same as O2 but in reverse)
- Higher pressure of CO2 in the blood going to the lungs than in the air of the lungs (so CO2 will dissolve out of the blood and into the air)
- CO2 is also lipid soluble
- Still a short distance for diffusion
- Still a large SA
63
Tell me about gas exchange of O2 with tissues?
Higher pressure of O2 in blood than there is in the interstitial fluid (so O2 will diffuse out of the blood and into the interstitial fluid)
64
Tell me about the gas exchange of CO2 with tissues?
The CO2 pressure is higher in the interstitial fluid than it is in the blood (so it will diffuse out of the interstitial fluid and into the blood)
65
What carries O2 in blood?
The hemoblobin in the red blood cells carries the O2.
Each hemoglobin has 4 "Hemes"
each Heme can carry 1 O2.
1 erythrocyte carries 4 O2 molecules
66
What 4 factors effect hemoglobins ability to bind (carry) O2?
1) PO2 (pressure of O2 of the blood)
2) Temperature
3) Blood pH (Bohr effect)
4) Metabolic activity of the RBC (production of BPG)
67
The higher the PO2 (pressure O2) = ______?
The higher the HbO2%
68
Where does glomerular filtration occur?
In the renal capsule between the glomerulus and the glomerular capsule.
- fluid moves from the blood (in the glomerulus) to the glomerular capsule
69
What 3 parts cross the filtration membrane and what is too large to pass through?
1.Capillary, endothelium, basement membrane and filtration slits.
2. Very fine filters, so only very small particles ( less than 3nm) can get through
3. Blood cells are too large to pass through
4. Most proteins are too large, and are also barred due to their negative charge.
70
What small molecules will get through the glomerular filtration?
Water
Glucose
Urea
Amino acids
Certain ions
71
Glomerular filtration is governed by two basic factors. What are they?
Hydrostatic pressure and osmotic pressure
72
What 4 forces are involved with glomerular filtration?
1) GHP (Glomerular hydrostatic pressure)
2) BCOP (Blood colliod osmotic pressure)
3) NFP (Net filtration pressure)
4) CsHP (Capsular hydrosatic pressure)
73
Explain hydrostatic pressure in glomerular filtration.
Net hydrostatic pressure = GHP-CsHP
(From slide in lecture) Net HP=50mmHg-15mmHg=35mmHg
Tends to push water and solute molecules out of the plasma (into the filtrate)
74
Explain osmotic pressure in glomerular filtration.
Net osmotic pressure = BCOP (Blood celled osmotic pressure)-CsHP(Capsular hydrostatic pressure)
(From slide in lecture): Net OP=25mmHg-0mmHg=25mmHg
Tends to draw water out of filtrate (into the plasma).
75
What is GFR?
Glomerular filtration rate
- Amount of filtrate produced from the kidneys each minute. (Avg 125mL/min)
**filtrate = fluid that has left the blood in the glomerulus and has entered the neprhon
76
How can you change glomerular hydrostatic pressure?
By changing the diameter of the afferent and/or efferent arterioles.
77
What happens if you Decrease the diameter of afferent arterioles and/or increase the diameter of Efferent arteriole?
This will decrease the pressure in the glomerulus (decrease GHP and therefore also decrease Net FP)
78
GFR depends on _________?
Filtration pressure
*when blood pressure changes thoughtout the day the kidneys need to work to maintain the glomeruluar hydrostatic pressure
79
What happens if you decrease the diameter of efferent arterioles and/or increase the diameter of afferent arterioles?
This will increase the pressure in glomerulus (increase GHP and therefore also increase Net FP)
80
How is GFR regulated?
1) Autoregulation (local effects)
2) Autonomic regulations (sympathetic NS)
3) Hormones (natruiretic peptides & the renin-angiotensin-aldorsterone system)
***IN GENERAL (changing the filtration pressure)
81
What’s the difference between afferent and efferent arterioles?
The Afferent arteriole aids in delivering deoxygenated blood from the lungs back into circulation.
The Efferent arteriole aids in the return of oxygenated blood from the heart to the lungs.
82
Explain Autoregulation (local effects) in relation to GFR.
Local effects on diameter of afferent arteriole and efferent arteriole (as described earlier).
83
Explain autonomic regulation in relation to GFR.
Sympathetic nerve fibres- causes vasoconstriction of afferent arterioles of glomerulus which will decrease GFR (it overrides the local effects in case of “emergency” to ensure adequate blood flow to other organs.)
84
Explain Hormonal regulation in relation to GFR, and gives some examples of Hormones.
Many hormones affect kidney function in general, and GFR in particular. These include: The natriuretic peptides (ANP0, and the renin-angiotensin-aldosterone system (RAAS)
85
What is a myogenic mechanism
The muscle in the afferent arteriole, when stretched it has a localized vasoconstriction, dropping the pressure in the glomerulus to keep it from getting too hot.
86
What 4 things happen in the (PCT) Proximal Convoluted Tubule? (simple)
1) Reabsorption of organic nutrients
2) Active reabsorption of ions
3) Reabsorption of water
4) Active secretion (ions, drugs, byproducts)
87
Tubuloglomerular feedback
The Nephrons communication between the Distal tubule and the glomerulus to regulate filtration.
88
What happens in the Loop of Henle (Nephron loop)?
60-70% of filtrate is reabsorbed in the PCT (before it reaches the Loop of Henle).
What’s left of the filtrate, the Loop of Henle reabsorbs.
Which includes:
-50% of the water
-66% of the Na+ and Cl- ions
-Collectively, this plays an important role in creating the circumstances that allow us to make concentrated urine.
89
What organic nutrients are reabsorbed in the PCT (proximal convoluted tubule)?
And what mechanisms are used for this?
-99% glucose, amino acids are reabsorbed back INTO the blood.
- Facilitated diffusion and cotransport (Na+ secondary active transport)
90
What happens in the Distal convolute tubule? (Detailed explanation)
Only 15-20% of filtrate remains by the time it reaches the DCT (Most of it already reabsorbed by the PCT and Loop of Henle)
“Final adjustments” in the composition of filtrate
Some more Na+ reabsorption (some of which controlled by aldosterone).
Ca2+ reabsorption (by carrier mediated transport, stimulated by certain hormones)
Plus Secretion (K+, H+, some hormones, foreign chemicals)
91
What mechanisms are used for the active reabsorption of ions in the PCT?
Cotransport and counter- transport
92
What mechanisms are used for the reabsorption of water in the PCT?
Osmosis (driven by HIGH osmotic pressure and LOW hydrosatic pressure of the peritubular capilarries)
**active transport of solutes creates a concentration gradient and water follows
93
What is secreted in the DCT and what does it help maintain?
K+ (removed from blood in exchange for Na+)
H+ (Helps maintain pH homeostasis, countertransport with Na+ ions)
94
under the influence of aldosterone we have a higher secretion of potasium?????? FUCK SHIT CUNT BALLS COCK
:')
95
what does antiduiretic hormone ADH do to the collecting duct?
lots of water will leave the collecting duct (will be reabsorbed back into the blood).
96
What two variables can we observe and test in urine?
Composition and concentration
97
What two sphincters must Urine pass through to be removed from the body? What kind of muscle is it? and is it voluntary or involuntary?
1. Internal Urethral sphincter (Smooth muscle, involuntary)
2. External urethral sphincter (Skeletal muscle, voluntary)
*Reinforced by muscles on the pelvic floor*
98
What happens during the Urine-voiding reflex (micturition reflex)
Stretching of the bladder stimulates the contraction of the bladder, leads to opening of internal urethral sphincter.
99
In simple terms what does the natriuretic peptide do?
Lowers blood pressure, either ANP (atrial natriuretic peptide released by cells of right atrium) or BNP (Brain natriuretic peptide released by cells of ventricule).
100
Explain in more detail the decrease in systemic blood pressure due to Natriuretic peptide.
Widespread vasodilation
Decreasing Na+ reabsorption (by inhibiting RAAS)
Decreasing ADH secretion
Decreasing thirst
Increasing pressure in the glomerulus (by vasodilation of afferent arterioles and vasoconstriction of efferent arterioles.)
101
In simple terms what does RAAS ( Renin-angiotensin-aldosterone-system) do?
Elevates blood volume and blood pressure.
102
What are some detailed effects of RAAS?
Widespread vasoconstriction (to increase systemic BP)
Constriction of afferent and efferent arterioles in the kidneys (Maintain GFR, decrease renal blood flow, and preserve Na+ and water that would be lost in urine.)
Increase salt (and water) reabsorption (to increase blood volume)
Stimulates ADH secretion and increases thirst (to increase blood volume)
103
Why is aldosterone released and where is it released from (simple)
Released from adrenal cortex due to RAAS activation ( low Na+, low BP and low ECF volume)
and/or, High K+ in the body's ECF
104
What is the general function of the Urinary system?
Fluid, electrolyte and pH balance by adjusting blood volume (regulation of water that gets excreted vs reabsorbed).
Regulation of several blood components (plasma concentration of Na+, K+ and Cl-).
Blood pH levels
Removing and filtering toxins, drugs and nitrogenous wastes.
Fuck
Rubbers
Be
Responsible
105
What happens if you decrease the diameter of the afferent arteriole?
Will decrease pressure in glomerulus (decrease GHP and therefore also decrease Net Filtrate pressure)
106
What happens if you increase the diameter of the efferent arteriole?
Will decrease pressure in glomerulus (decrease GHP and therefore also decrease Net filtrate pressure)
107
What happens if you increase the diameter of the afferent arteriole?
Will increase pressure in the glomerulus (increase GHP and the net filtrate pressure).
108
What happens if you decrease the diameter of the efferent arteriole?
Will increase pressure in the glomerulus (increase GHP and Net filtrate pressure)
109
Natriuretic peptides block what other hormone?
Blocks Anti-diuretic hormone.
110
What is angiotensin II stimulated by?
Low arterial pressure
111
What effect does angiotensin II have on the glomerulus?
*Detailed*
It constricts the efferent arteriole, increasing Glomerular hydrostatic pressure (GHP), increasing GFR and NFP.
Increases Na+ reabsorption in the PCT and regulates blood volume
increase Aldosterone and ADH
112
Aldosterone is produced in response to what?
Low blood volume via the RAAS
113
Aldosterone has its effects on what parts of the Nephron? And what does it help secrete/reabsorb
Effects the DCT and Collecting duct primarily.
helps in the reabsorption of Na+ and secretes K+ and H+
*Stimulated by the high K+ concentration in blood*
114
Due to the DCT and collecting ducts impermeability to water, how does Anti-diuretic hormone help change this?
ADH opens channels allowing the DCT and Collecting duct to become permeable to water.
***ADH is responsible for concentration and dilution of urine***
115
Atrial Natriuretic peptide is released due to high atrial pressure, what effects follow this release?
Since it's a natriuretic, it increases GFR.
Also inhibits RAAS which in turn reduces Na+ reabsorption.
116
Counter Current mechanism is made up of what two things?
Loop of Henle and Vasa recta
117
If temperatures are higher will Hb have a higher or lower affinity for O2?
Lower.
So Hb will release O2 more often if the temperature is high
and vice versa
*the lower the temp the higher the affinity and Hb wont release O2
118
What does low pH (acidic) do to Hb?
it changes it shape so Hb will release O2 more often
*called the Bohr effect
119
What does a higher concentration of BPGs in red blood cells do to Hb?
Hb will release more O2
*BPG levels can be increased by at higher (basic) pH so O2 gets released
*Bohr effect can help release O2 at low pH (acidic)
120
What 2 effects can make it easier for Hb to release O2?
Bohr effect (helps at low pH)
BPG effect (helps at high pH)
121
Tell me about fetal Hb?
Has a higher affinity for O2
*important because it allows the fetus' RBC to take O2 from the adult Hb (across the placenta)
122
What other factors can effect the transport of O2 to tissues?
CO (carbon monoxide) will compete with O2 for "space" on Hb
123
What type of affinity does CO have for Hb?
Has a much higher affinity for Hb than O2 has (even though the P co is so low)
High altitudes (low Po2 at higher altitudes)
124
What are the 3 ways CO2 is carried in blood?
1) as Carbonic acid (bicarbonate ion) 70%
2) Bound to Hemoglobin (HbCO2) (23%)
3) Dissolved in the plasma (7%)
125
What does the enzyme carbonic anhydrase do?
Helps to quickly convert CO2 into H2CO3 (carbonic acid) in RBCs
126
What does carbonic acid (H2CO3) do?
(Chloride shift)
It dissasociates to form hydrogen ions and bicarbonate ions so that the H+ ions can leave the RBCs and enter the plasma (which decreased the pH from basic to more neutral or acidic)
The bicarbonate ion (HCO3-) get "traded" and leave into the plasma and chloride ions (Cl-) enter the RBC
127
What are the respiratory centers in the brain?
Medulla oblongata and the Pons
*receive input and send out nervous impulses to the motor neurons of the spinal cord
128
Tell me about the medula oblongata?
(Receives respiratory input)
Dorsal respiratory group (DRG) (rhythmic centers): Inspiratory center. Active for every inhale
Ventral respiratory group (VRG) (rhythmic centers): Expiratory center. (Active for every exhale. *also aids in maximum inhalation
129
What is reciprocal inhibition ?
prevents inhalation and exhalation from happening at the same time
130
Tell me about the Pons
Regulates the shift from inhalation to exhalation. (Pneumotaxic center)
Inhibits the DRG (ending inspiration)
*more stimulus to the pons means faster breathing (shorter breaths)
*less stimulus to the pons means slower deeper breathing (longer breaths)
(Apneustic centers) Promote inhalation by stimulating the DRG
131
What 5 things to respiratory reflexes respond to?
1) Chemoreceptors: (Pco2, Po2, pH, of blood or cfs)
2) Baroreceptors:
3) Stretch receptors: (change in lung volume. Hering-breuer reflex)
4) Physical or chemical irritants: (in conducting portsion of respt tract)
5) Pain/ body temp/ abnormal visceral sensations
132
What is the Hering-breuer reflex?
Stretch receptor
*It inhibits inhalation if the lungs are already full/inflated
133
What is CHP?
Capillary hydrostatic pressure
blood pressure in the capillary bed pushes fluid out of the capillary.
134
What is IHP?
Interstitial hydrostatic pressure
Fluid pressure of interstitial fluid.
135
What is BCOP?
Blood colloid osmotic pressure
pressure due to osmolarity of blood
*pulls water into the capillaries via osmosis
(colloid = a protein suspension)
136
What is ICOP?
Interstitial colloid osmotic pressure
Pulling water into the interstitial space via osmosis
137
What is net hydrostatic pressure?
CHP - IHP = net hp
138
What is net colloid osmotic pressure?
BCOP - ICOP = netCOP
139
What is net filtration pressure?
net hysrostatic pressure - net colloid osmotic pressure = NFP
Simplified one:
CHP - BCOP = NFP
140
What is the main function of RAAS?
The main function of the RAAS is to increase blood pressure and maintain blood flow to vital organs during times of low blood volume or pressure.
141
Main function of angiotensin II?
narrows blood vessels and increases blood pressure. also helps promote the release of ADH to increase water reabsorption.
