Capillary dynamics / GFR dynamics
Define the equation that determines flow in the Glomerulus
GFR = Glomerular hydrostatic pressure - (Glomerular colloid osmotic pressure + Bowman's capsule hydrostatic pressure)
You stand up quickly after gardening and feel lightheaded for 15 seconds-- but then return to normal. What form of BP regulation has occurred?
Neural control / short-term
Reflex mediated through baroreceptors & chemoreceptors in the aorta and carotids
Sensory signal -> cardiovascular centers in the medulla -> correction in BP
To cause inspiration, we must _____ thoracic volume and ____ thoracic pressure.
To cause inspiration, we must increase thoracic volume and decrease thoracic pressure.
Pressure flows high -> low.
When PO2 is high, Hemoglobin percent O2 saturation will be ______
High
- Hb saturation is high when PO2 is high (lungs)
- Hb saturation is low when PO2 is low (tissues)
This REFLEX demonstrates the increase of cardiac output from the increase in HEART RATE
Bainbridge Reflex
- Adjusts heart rate in response to venous return
- Triggers increase in heart rate through increased sympathetic activity to SA node only
Hypoalbumina causes what condition in the tissues
Edema
What are our two forms of auto-regulation
Metabolic control: Nutritional status of tissues regulate capillary sphincters
Myogenic control: Vaso-musculature automatically counters shift in vascular muscle stretch
Our diaphragm is a ____ muscle and contracts _____ to cause inspiration (breathing in).
Our diaphragm is a skeletal / voluntary muscle and contracts downwards to cause inspiration (breathing in).
How many O2 molecules can one hemoglobin carry?
4
The _____ is where the vast majority of reabsorption occurs in the nephron
Proximal Convoluted Tubule (PCT)
- Functions to reabsorb nutrients, electrolytes, and water from the glomerular filtrate back into the bloodstream
What system will drain excess fluid from the tissues that were unable to return to the capillaries / venules?
Lymphatic system will drain excess fluid as lymph which will re-enter venous return around the SVC / IVC.
If our blood pressure is too high, myocytes in our atria may respond to stretch by producing _____ which will increase our GFR to excrete water and sodium, lowering our blood volume and blood pressure
Cardiac myocytes will produce Atrial natriuretic peptide (ANP) in response to increased stretch (increased venous return) to increase our GFR and excrete H2O and Na+. This will decrease blood volume and thus decrease blood pressure.
Explain why our intra-pleural pressure is more / less negative than our intrapulmonary pressure
Our intra-pleural pressure is more negative than our intrapulmonary pressure to help prevent collapse (from alveolar surface tension) / increase lung expansion.
Increased temperature, PCO2, BPG, and decreased pH will cause a right shift to allow for increased / faster oxygen offloading.
Where is renin produced, and what will renin cause to be produced
Renin is produced in the kidneys (Juxtaglomerular cells), and will cause the release of Angiotensin I.
Explain how we can increase or decrease glomerular hydrostatic pressure relative to the arterioles
To increase glomerular hydrostatic pressure, you can dilate the afferent arteriole
To decrease glomerular hydrostatic pressure, you can constrict the afferent arteriole
Over a lifetime, our ____ system will monitor BP and make corrections through increasing or decreasing ______
Over a lifetime (long-term), our kidneys / renal system will monitor BP and make corrections through increasing or decreasing urine production, EPO release, and renin release.
Premature babies may lack the healthy development of Type II Septal cells within the alveoli. Explain what substance the baby can not produce, and why this will cause the baby to be unable to breath on their own.
Type II Septal cells produce Surfactant, which breaks up alveolar surface tension. Alveolar surface tension is a collapsing force of the lungs, and without surfactant the lungs will be more likely to collapse and less likely to inflate, severely limiting the baby's ability to perform ventilation.
Which side is the products of this equation when in the lungs?
CO2 + H2O () H2CO3 () H+ + HCO3-
CO2 + H2O
- We make carbon dioxide and water vapor in our lungs to expire the byproducts of cellular metabolism (H+ + HCO3-) which will be the reactants
Increased sudden stretch in the vascular smooth muscles will cause _____ in the vascular musculature.
Vasoconstriction, this is Myogenic control.
What extrinsic factor has the largest positive impact on change in GFR rate
Atrial natriuretic peptide (ANP)
ANP makes salty pee
If an individual has chronically high BP (hypertensive) we may prescribe an ACE inhibitor (i.e., lisinopril). Explain how this ACE inhibitor can lower blood pressure in the intermediate term.
ACE = Angiotensin converting enzyme, which converts Angiotensin I into Angiotensin II (powerful vasoconstrictor, increases BP). If we block the effects of ACE, we can block production of Angiotensin II -- thereby decreasing blood pressure.
If the alveoli are damaged and become clumps of 'one big alveolus,' it will decrease relative alveolar surface tension. What is the effect of decreased alveolar surface tension on an individuals breathing pattern?
Decreased alveolar surface tension causes a decreased ability to collapse the lungs.
Decreased ability to collapse the lungs causes a decreased ability to exhale residual air in the lungs
This is emphysema (don't smoke cigarettes)
By exporting HCO3- into the bloodstream, we can increase HCO3- production within the cell (Le Chatelier's)
By increasing HCO3- production, we can increase CO2 production (byproduct of metabolism)
By using Cl- anion we avoid depolarization of the RBC
Explain where the proton in the following equation:
HHb + O2 -> HbO2 + H+
Will be used to avoid a decrease in pH within the lungs
The proton produced by the formation of oxyhemoglobin (HbO2) will be utilized in the following reaction:
CO2 + H2O <- H2CO3 <- H+ + HCO3-
Thereby avoiding a decrease in pH or increase in [H+]