Term
| Ion regulation is a key feature of kidney function. What happens to the resting membrane potential of a neuron if extracellular K+ levels decrease? |
|
Definition
| If extracellular K+ decreases, more K+ leaves the neuron, and the membrane potential hyperpolarizes. |
|
|
Term
| What happens to the force of cardiac contraction if plasma Ca+ levels decrease substantially. |
|
Definition
| If plasma Ca+ decreases, the force of contraction decreases. |
|
|
Term
| What would happen to the body if filtration continued at a normal rate but reabsorption dropped to half the normal rate? |
|
Definition
| If reabsorption decreases to half the normal rate, the body would run out of plasma in under an hour |
|
|
Term
| If systemic blood pressure remains constant but the afferent arteriole of a nephron constricts, what happens to renal blood flow and FGR in that nephron? |
|
Definition
| If the afferent arteriole constricts, the resistance in that arteriole increaes, and blood flow through that arteriole is diverted to lower r esistance arterioles. GFR will decrease in the nephron whose arteriole constricted. |
|
|
Term
| Explain why a decrease in plasma protein concentration causes an increase in GFR? |
|
Definition
| The primary driving force for GFR is blood pressure opposed by fluid pressure in Bowman's capsule and colloid osmotic pressure due to plasma proteins. With fewer plasma proteins, the plasma has lower than normal colloid osmotic pressure. With less colloid osmotic pressure opposing GFR, GFR increases. |
|
|
Term
| How does reabsorbed fluid get into the capillaries from the interstitial fluid? |
|
Definition
| The driving force for reabsorption from the interstital fluid into the capillaries is the low hydrostatic pressure that exists along the entire length of the peritubular capillaires. This low pressure favors reabsorption. |
|
|
Term
| If plasma creatinine = 1.8/ 100 mL plasma, urine creatinine = 1.5 mg/mL urine, and urine volume is 1100 mL in 24 hours, what is the creatinine clearance? What is GFR? |
|
Definition
Creatinine clearance = creatinine exretion rate / (creatinine) plasma which is
1.5 mg cretinine / mL urine X 1.1 L urine / day/1.8 mg creatinin / 100 mL plasma. Creatinine clearance is about 92 L/day and GFR is equal to creatinine clearance. |
|
|
Term
| Describe teh changes in hte conducting ducts of hte lungs as respiratory ducts get smaller. From Ciliated columnar epithelium to Simple Squamous epithelium. |
|
Definition
| Ciliated columnar epithelium with goblet cells, changes to ciliated columnar epithelium with no goblet cells, changes to simple cuboidal epithelium, changes to simple squamous epithelium. |
|
|
Term
| Without cilia and mucous to trap bacteria, dust, etc., our lungs must rely on WHAT to remove debris and microbes? |
|
Definition
|
|
Term
| As respiratory ducts get smaller, what happens to the amount of cartilage? What happens to the amount of smooth muscle? |
|
Definition
| Amount of cartilage decreases and the amount of smooth muscle increases |
|
|
Term
| Put the following in order from largest to smallest. Bronchioles, terminal bronchioles, alveolar ducts, primary bronchus, secondary bronchi, tertiary bronchi, pharynx, trachea, larynx, respiratory bronchioles, alveolar sacs. |
|
Definition
1. pharynx
2. larynx
3 trachea
4 primary bronchi
5 secondary bronchi
6 tertiary bronchi,
7bronchioles
8 terminal bronchioles
9 respiratory bronchioles
10 alveolar ducts
11 alveolar sacs |
|
|
Term
| Where does gas flow stop and diffusion take over in the respiratory tree? |
|
Definition
|
|
Term
| Name 2 types of alveolar cells and briefly describe the function of each |
|
Definition
Type 1 - simple squamous epithelial; fxn, Diffusion
Type II - surfactant producing cells |
|
|
Term
| Explain the function of surfactant |
|
Definition
| Soapy substance that reduced surface tension of water coating inside alveoli so that cells do not stick together during expiration; necessary so that alveoli can reinflate (expand) |
|
|
Term
| What is the advantage of a lung being composed of 150 million alveoli over a lung composed of one big sac? |
|
Definition
| Increased surface area so that more gas diffusion can take place |
|
|
Term
| Name a condition that reduces the # of alveoli? |
|
Definition
|
|
Term
| What are the 4 major steps of respiration? |
|
Definition
1. Pulmonary ventilation
2. Pulmonary Respiration
3. Tissue Respiration
4. Cellular Respiration |
|
|
Term
|
Definition
| Breathing; gas exchange between atmosphere and lungs |
|
|
Term
|
Definition
| gas exchange between external environment and blood |
|
|
Term
|
Definition
| Gas exchange between blood and tissues |
|
|
Term
|
Definition
| aerobic respiration (glycolysis, pyruvic acid oxidation, Kreb's cycle, electron transport system); oxygen is the final electron acceptor in the ETC |
|
|
Term
| Pulmonary ventilation involves gas exchange between? |
|
Definition
|
|
Term
| Explain the linings of the pleural cavity. |
|
Definition
| Pleural cavity is lined with parietal pleura (serious membrane); lungs are covered with visceral pleura (serous membrane) ; between the two membranes is a thin layer of pleural fluid. |
|
|
Term
| What are the 3 pressures involves in pulmonary ventilation? |
|
Definition
1. Atmospheric (barometric) pressure
2. Intrapulmonary (intra-alveolar) Pressure
3. Intrapleural (intrathoracic) pressure |
|
|
Term
| Atmospheric (barometric) pressure |
|
Definition
| pressure exerted by air surrounding body (760 mm Hg at sea level) |
|
|
Term
| Intrapulmonary (intra-alveolar) pressure |
|
Definition
| pressure within the alveoli; fluctuates with phases of breathing |
|
|
Term
| Intrapleural (intrathoracic) pressure |
|
Definition
| pressure within the pleural cavity; fluctuates with breathing phases, but is about 4 mm Hg less than intrapulmonary pressure during an inspiration |
|
|
Term
| What is atmospheric pressure at sea level? |
|
Definition
|
|
Term
| Why must intrapleural pressure alwyas be a little less than intrapulmonary pressure? |
|
Definition
| If intrapleural pressure equals or exceeds intrapulmonary pressure, the lungs will collapse immediately. It's the difference between the intrapulmonary and intrapleural pressures that keeps the alveoli open (called transpulmonary pressure) |
|
|
Term
| What might cause intrapleural pressure to equal or exceed intrapulmonary pressure? |
|
Definition
1. If amount of pleural fluid (seroud fluid) in pleural cavity increaes (pleurisy from inflammation)
2. Pneumothorax - wound allows air to enter intrapleural space |
|
|
Term
|
Definition
| Volume changes lead to pressure changes; which lead to the flow of gases to equalize the pressure; increase volume, decrease pressure; decrease volume, increase pressure |
|
|
Term
| How do we increase the volume of the thoracic cavity? |
|
Definition
| It is an active process involving skeletal muscle contraction; diaphragm and extern intercostals muscles. |
|
|
Term
| How do we decrease the volume of the thoracic cavity? |
|
Definition
| It is a passive process involving skeletal muscle relaxation; diaphragm and external intercostal muscles. |
|
|
Term
| Describe the diaphragm in its relaxed state and in its contracted state |
|
Definition
1. Relaxed diaphragm - diaphragm is long and it bubbles up into the thoracic cavity.
2. Contracted diaphragm - diaphragm is short and it stretches across the bottom of the thoracic cavity. |
|
|
Term
| Atmospheric pressure is 749 mm Hg. Lung pressure is 747. What will happen? |
|
Definition
| Inspiration - air moves from high pressure to low pressure into the lungs |
|
|
Term
| How can you increase the amount of air exhaled? |
|
Definition
| Forced expiration; Contract abdominal muscles; they compress the abdomen, pushing up on the diaphragm, causing it to bubble up more into the thoracic cavity; this decreases the volume of the thoracic cavity even more, which increases pressure wven more. Also contract internal intercostal muscles - they pull the rib cage down even more, reducing volume and increasing pressure. |
|
|
Term
| What are 3 major factors influecing ventilation? |
|
Definition
1. airway resistance
2. elastic recoil
3. Lung compliance |
|
|
Term
|
Definition
| Friction or drag encountered in respiratory passageways. |
|
|
Term
|
Definition
| refers to how readily the lungs rebound (return to original volume) after being stretched. |
|
|
Term
|
Definition
| the stretchiness of the lungs; the ease with which they expand |
|
|
Term
| What determines airway resistance? |
|
Definition
| Friction or drag caused by the wall of the tube |
|
|
Term
| What is the relationship between gas flow and resistance? |
|
Definition
| Inverse; increase resistance (ex, decreased Diameter - COPD) ----> decrease gas flow |
|
|
Term
| Explain elastic recoil - recoil depends on what 2 factors |
|
Definition
Refers to how readily the lungs rebound (return original volume) after being stretched; responsible for lungs returning to pre inspiratory volume when diaphragm and ext. intercostals relax.
2 factors:
1. elastic connective tissue in lungs
2. alveolar surface tension |
|
|
Term
| How does surfactant effect elastic recoil? |
|
Definition
| Surfactant decreases surface tension therefore decreases recoil. you do not want them to completely collapse; surfactant prevents this |
|
|
Term
| Exactly how does surfactant reduce surface tension? |
|
Definition
| Surface tension is due to the attraction between water molecules ( due to H bonds, water molecules are attracted to one another) This attraction (high surface tension) could cause the complete collapse of the alveoli during inspiration (the sides of the alveoli are attracted to one another). Surfactant is a soapy substance. The soap molecules get in between the water molecules, disrupting the H bonds between them, and therefore reducing surface tension. You want the lungs to recoil, but not completely collapse. |
|
|
Term
| What is Pneumothorax? What occurs durning this conditoni? |
|
Definition
| Occurs as the result of an open chest wound; when air enters the intrapleural space, pressure rises until its equal to atmospheric pressure. When intrapleural pressure is the same as intrapulmonary pressure (atmospheric pressure) the lung cannot expand and it collapses away from the chest wall. |
|
|
Term
| Lung compliance has to do with what? |
|
Definition
| How stretchy the lungs are |
|
|
Term
| What is affected by lung compliance? |
|
Definition
|
|
Term
| Name a condition that causes reduced compliance |
|
Definition
| pulmonary fibrosis - infiltration of lung tissue with connective tissue proteins. |
|
|
Term
| What is the maximum amount of air a person can exhale after taking the deepest breath possible (TV + IRV + ERV), |
|
Definition
|
|
Term
| What is the amount of air inahled over and above the tidal volue durnig a forced inspiration? |
|
Definition
| Inspiratory reserve volume |
|
|
Term
| What is the amount of air exhaled over and above the tidal volume during a forced expiration? |
|
Definition
| Expiratory reserve volume |
|
|
Term
| What is air entering the respiratory tract taht fails to reach the alveoli? |
|
Definition
|
|
Term
| What is the amount of air that enters the lungs during a normal quiet inspiration? |
|
Definition
|
|
Term
| What is the amount of air that leaves the lungs du ring a normal quiet expiration? |
|
Definition
|
|
Term
| What is the volume of air in lungs at end of normal passive expiration? (ERV + RV) |
|
Definition
| functional residual capacity |
|
|
Term
| What is normal value for vital capacity? |
|
Definition
| 4500 to 4800 mL (around 5000 mL) |
|
|
Term
| What is a normal Tidal Volume? |
|
Definition
|
|
Term
| What is normal dead space air? |
|
Definition
|
|
Term
| Explain why d uring expiration, 500 mL of air is exhaled, but only 350 mL of that is alveolar air. Where does the other 150 mL come from? |
|
Definition
| The other 150 comes from the dead space air that was already in the conduction zone; it fails to reach the respiratory zone. |
|
|
Term
| Explain why during inspiration 500 mL of fresh atmospheric air is inhaled, and on the next expiration, 150 mL of that fresh air is exhaled (how does it stay fresh? |
|
Definition
| 500 mL of fresh air came in, but only 350 made it to the respiratory zone; 150 mL of frsh air became dead space air. So that on the expiration, air from the alveoli pushed the dead space air (fresh air) out ahead of it. |
|
|
Term
| How much blood passes through the lungs each minute? |
|
Definition
|
|
Term
| How much oxygen does oxygen rich blood have? |
|
Definition
|
|
Term
| How much oxygen does oxygen poor blood have? |
|
Definition
|
|
Term
| How much oxygen is transported to xygen poor blood from alveoli each minute? |
|
Definition
|
|
Term
| Is more oxygen exhaled or inhaled each minute? |
|
Definition
|
|
Term
| What is the importance of still having lots of oxygen in "oxygen poor blood"? |
|
Definition
| oxygen reserve in case breathing is arrested |
|
|
Term
| In the lungs oxygen concentration are greater in the alveoli or arterioles? |
|
Definition
|
|
Term
| in the lugns carbon dioxide concentrations are greater in the alveoli or arterioles? |
|
Definition
|
|
Term
| What does hemoglobin saturation mean? |
|
Definition
| Every hem in a hemoglobin molecule is bound to an oxygen molecule for a total of 4 oxygen molecules carried by one hemoglobin moleucle |
|
|
Term
| What are the 3 ways and percentages that carbon dioxide can be transported in the blood? |
|
Definition
70% as bicarbonate ion in the plasma
23% as carbaminohemoglobin in the rbc
7% as dissolves CO2 in the plasma |
|
|
Term
| Write the chemical reaction that converts carbon dioxide in to hydrogen ion and bicarbonate ion |
|
Definition
Most of the CO2 in the blood (70%) diffuses from tissues into the rbc's in the capillaries and is combined with water to form carbonic acid. Carbonic acid dissociates into hydrogen ions and bicarbonate ions, which diffuse out of the rbc's and into the plasma.
CO2 + H20 ---> H2CO3 then
H2CO3 ---> H+ HCO3-
HCO3- then diffuses out of the rbc's and into the plasma and H+ binds to hemoglobin, so hemoglobin acts as a buffer |
|
|
Term
| Most carbon dioxide in the blood difsues into red blood cells and is combined with _________ to form _________ The acid then dissociates into _____________ ions and ____________ ions. The ____________ ions combine with hemoglobin. __________ ions diffuse out of the red blood cells into the plasma |
|
Definition
| Most carbon dioxide in the blood difsues into red blood cells and is combined with water to form carbonic acid. The acid then dissociates into hydrogen ions and bicarbonate ions. The hydrogen ions combine with hemoglobin. Bicarbonate ions diffuse out of the red blood cells into the plasma |
|
|
Term
| What is a buffer? How does hemoglobin act as a buffer? |
|
Definition
| Buffers help maintain pH by combining with or releasing hydrogen ions. Hemoglobin binds to H+ released by the dissociation of carbonic acid (hemoglobin acts as a base) |
|
|
Term
| What chemical reactions occur in the lung capillaries so that carbon dioxide can be released? |
|
Definition
| C02 + H20 <---- H2CO3 <---- H2CO3 <--- H+ HCO3- |
|
|
Term
| Carbon dioxide can bind directly to __________ in the rbc to produce a molecule called ____________ The carbon dioxide binds to the ________ of Hb, so it does not compete with _________ for binding sites |
|
Definition
| Carbon dioxide can bind directly to hemoglobin in the rbc to produce a molecule called Carbaminohemoglobin The carbon dioxide binds to the globin of Hb, so it does not compete with oxygenfor binding sites |
|
|
Term
| A small percentage of carbon dioxide is dissolves in blood......? |
|
Definition
|
|
Term
| Explain Dalton's Law of partial pressure |
|
Definition
| The total pressure of a gas mixture (air) is equal to the sum of the pressures tha teach gas in the mixture would exert independently (called partial pressure) |
|
|
Term
| What are the percentages of nitrogen, oxygen, and carbon dioxide in the atmospheric air? |
|
Definition
| 79% nitrogen, 21% oxygen, 0.04% carbon dioxide |
|
|
Term
| How do you calculate partial pressure for a particular gas? |
|
Definition
| The partial pressure of a particular gas is equal to the percentage of that gas in the atmosphere times the total atmospheric pressure |
|
|
Term
| What is the effect of water vapor on the partial pressure of oxygen? |
|
Definition
| decreases the partial pressure of oxygen. The partial pressure of a particular gas is diluted by the presence of water vapor. |
|
|
Term
| The relative humidity of air in the respiratory zone is what compared to atmospheric air? |
|
Definition
| more than atmospheric air. |
|
|
Term
| What is the relative humidity of air once it reaches the respiratory zone? why? |
|
Definition
| 100%. The air becomes completely saturated with water as it passes through the respiratory tree (humidified and warmed by goblet cell columnar epithelum |
|
|
Term
| The capacity of air to contain water dpeneds on what? |
|
Definition
|
|
Term
| Does the relative humidity of air in the respiratory zone fluctuate? Why? |
|
Definition
| No - Body temperature is realtively constant. |
|
|
Term
| What is the partial pressure of water vapor in the respiratory zone? |
|
Definition
|
|
Term
| How does increasing altitude affect atmospheric pressure? |
|
Definition
| decreases atmospheric pressure as you gain altitude. |
|
|
Term
| What happens to the partial pressure of oxygen as you inrease altitude? |
|
Definition
|
|
Term
| As you increase altitude - do lungs work harder for inspiration or expiration? Why? |
|
Definition
| Inspiration - remember that air will only move from high pressure to low pressure, so lung pressure has to be lower than atmospheric pressure for an inspiration to occur. At high altitudes ( low pressure) it is difficult to make lung pressure lower than thsi low atmospheric pressure, thus the body does not get enough oxygen. |
|
|
Term
| How can decompression sickness be prevented? |
|
Definition
| Slow ascent to allow nitrogen to leave the blood in expiration. Decompression sickness can occur when giong from high pressure to low pressure. if the change is made too quicly, then dissolves nitrogen comes out of solution, forming gas bubbles, w hich can block small blood vessels. |
|
|
Term
| Why would the partial pressure for oxygen in the blood of pulmonary veins be the same as taht in the systemic arteries? |
|
Definition
| They both carry high oxygen "oxygen rich" blood. |
|
|
Term
| Why would the partial pressure for oxygen in the blood of pulmonary arteries be the same as that in the systemic veins? |
|
Definition
| They both carry low oxygen "oxygen poor" blood. |
|
|
Term
| What do oxyhemoglobin curves tell us? |
|
Definition
| The % of hemoglobin molecules that have oxygen attached at a given PO2 partial pressure of oxygen. |
|
|
Term
| What is the relationship between partial pressure of oxygen and hemoglobni saturation? |
|
Definition
| High partial pressure promotes oxygen loading and saturation. |
|
|
Term
| If rbc's lack mitochondria, how do they produce ATP? |
|
Definition
| Glycolysis, (it is anaerobic, makes ATP without oxygen; not linked to the ETC that uses oxygen as the final electron acceptor) |
|
|
Term
| What metabolite from glycolysis is important in oxygen loading unloading by hemoglobin? |
|
Definition
|
|
Term
| Production of 2,3 DPG increases or decreases in the absence of oxyhemoglobin? |
|
Definition
|
|
Term
| When might oxyhemoglobin levels be low? |
|
Definition
|
|
Term
| What effect does 2,3 DPG have on oxygen loading by hemoglobin? |
|
Definition
|
|
Term
| The Bohr effect - as pH DECREASES hemoglobin releases oxygen more readily Why? |
|
Definition
| H+ combines with the hemoglobin protein, changes its shape and causing it to unload oxygen. |
|
|
Term
| Low pH maens what to hydrogen ion concnetration? |
|
Definition
| higher hydrogen ion concentration |
|
|
Term
| higher hydrogen ion concentration promotes oxygen binding or release and in what capillaries? |
|
Definition
| higher hydrogen ion concentration promotes oxygen binding in the pulmonary capillaries. |
|
|
Term
| What is the relationship between CO2 and pH? |
|
Definition
| Inverse; Increase CO2 levels ---> increase carbonic acid levels ----> increase H + levels ----> decrease pH |
|
|
Term
| Describe the Haldane effect. |
|
Definition
| Resutls from Bohr effect; deoxygenation of hemoglobin increases its affinity for H+ allows more CO2 to be removed from the tissues ( remember CO2 combines with water to form carbonic acid, which dissociaties into H+ and bicarbonate ion |
|
|
Term
| In lung capillaries is pH higher or lower than systemic capillaries. How does this effect oxygen loading? |
|
Definition
| Lung capillaries enjoy a higher pH favoring oxygen loading. |
|
|
Term
| Lower pH promotes oxygen loading or unloading? |
|
Definition
| unloading like in active tissues. |
|
|
Term
| Higher temperatures promote oxygen binding or release? |
|
Definition
|
|
Term
| If sufficient oxygen is not present what kind of metabolism occurs? |
|
Definition
| Anaerobic fermentation (lactic acid fermentation |
|
|
Term
| Explain the Hering-Breuer Reflex and baroreceptors |
|
Definition
| Visceral pleurae and respiratory passageways contain stretch receptors (baroreceptors) taht are stimualted when lugns are infalted; they send inhibitory impulese to the medulla oblongata via the vagus nerves; this ends inspiration and allows expiration to occur; as the lung recoil (go back to their original volume) the baroreceptors become quiet (they are only stimualted on the inspiration) and the medulla oblongata halts its inhiboitory influence. This allows next inspiration to occur. |
|
|
Term
| What stimulates mechanoreceptors? |
|
Definition
|
|
Term
| mechanoreceptors have an inhibitory effect to bring an end to? |
|
Definition
|
|
Term
| Where are chemorecptors sensitive to blood oxygen and blood pH found? |
|
Definition
Aortic Bodies
Carotid Bodies
Medulla Oblongata |
|
|
Term
| What stimulates hyperventilation? |
|
Definition
|
|
Term
| What stimulates hypoventilation? |
|
Definition
|
|
Term
| Why does excercise cause you to hyperventilate? |
|
Definition
1. Increase CO2 produced from inreased metabolism in skeltal muscles
2. anaerobic fermentation produces lactic acid. |
|
|
Term
| Why does vomiting cause you to hypoventilate? |
|
Definition
| Vomiting depletes the stomach of hydrochloric acid (HCl) so blood H+ levels decrease as the body tries to replace stomach acid. |
|
|
Term
| What is the effects of Nicotine on the lungs? |
|
Definition
| Nicotine constricts terminal bronchioles and this decreases airflow in and out of hte lungs |
|
|
Term
| What is the effect of CO on the l ungs? |
|
Definition
| CO in smoke binds to hemoglobin and reduces its oxygen carrying capacity |
|
|
Term
| What is the effects of irritants on the lungs |
|
Definition
Irritatns in smoke cause increased fluid secretion by the mucosa of the bronchial tree and swelling of the mucosal lining, impeding airflow. Irritants also inhibit the movement of cilia of the columnar epithelial cells, thus excess fluid and foreign debris are not easily removed.
Smoking also leads to the destruction of elastic fibers in the lungs, causing emphysema. |
|
|
Term
| Describe what occurs in the lungs during an asthma attack? |
|
Definition
| Chronic, Inflammatory disorder that produces sporadic narrowing of airways, Attacks are brought on by spasms of the smooth muscles in the walls of the smaller bronchi and bronchioles, causing bronchoconstriction. There may also be excessive secretion of mucous. Common triggers may include allergens (pollen, dust mite, molds fods,) emotion upset, aspirin, Sulfiting agents (used in beer, wine etct) excercise,a dn cig smoke. |
|
|
Term
| What happens in the lungs of cystic fibrosis patients? |
|
Definition
Thick mucous secretions build up in the airways blocking them.
This disease also affects the pancrease. So the patient fails to produce digestive enzymes. |
|
|
Term
| If asthma and COPD are both obstructive pulmonary diseases, how are they different? |
|
Definition
| Obstruction with asthma is largely reversible with inhalation of a bronchodilator like albuterol. COPD is not. The vast majority of patients with COPD are smokers, Asthma can be caused by a variety of allergens. |
|
|
Term
| What 3 endocrine hormones are produced by the kidneys? |
|
Definition
1. Erythropoietin - stimulates the production in red bone marrow when blood oxygen levels are low.
2. Calcitriol - from vitamin D. increases calcium absorption in the small intestines
3. Angiotensin II - mechanism that increases blood pressure |
|
|
Term
| What is a toxic waste product formed from protein metabolism? |
|
Definition
|
|
Term
| How does Ammonia increase blood pH? |
|
Definition
| It acts as a base, combining with H+ ions |
|
|
Term
|
Definition
| From 2 ammonia and CO2, it is produced by the liver and excreted by the kidneys |
|
|
Term
| What is a waste product formed from nucleotide metabolism? |
|
Definition
|
|
Term
| What causes gouty arthritis? |
|
Definition
| diet high in nucleic acids, crystals of a salt formed from sodium urate and result in gouty arthritis. |
|
|
Term
| Why is it important that the kidneys maintain an isotonic environment for body cells? |
|
Definition
| so that lysis/crenation of cell does not occur |
|
|
Term
| Why is it important that kidneys help maintain pH homeostasis? |
|
Definition
| Extreme pHs affect protein structure, which then affects protein function |
|
|
Term
| Each renal pyramid terminates in a _________________ which projects into a cup shaped tube called a _____________ |
|
Definition
Each renal pyramid terminates in a renal papilla which projects into a cup shaped tube called a
renal calyx |
|
|
Term
| Name the 2 types of nephrons? |
|
Definition
| Cortical and juxtamedullary nephrons |
|
|
Term
| There are more of which type of nephron? |
|
Definition
|
|
Term
| Which type ha sa long loop of Henle? |
|
Definition
|
|
Term
| Which type has vesa recta capillaries? |
|
Definition
|
|
Term
| Which type has peritubular capillaries? |
|
Definition
|
|
Term
| What are the 2 main structures of each nephron? |
|
Definition
| renal corpuscle and renal tubule |
|
|
Term
| name 2 parts of the renal corpuscle? |
|
Definition
| Glomerulus and bowmans' capsule |
|
|
Term
| Wha tlayer of the capsule covers the glomerulus? |
|
Definition
|
|
Term
| what layer of the capsule forms the outer wall fo the capsule? |
|
Definition
|
|
Term
| what "foot cells" make up the VISCERAL layer of the Bowman's capsule? |
|
Definition
|
|
Term
| What are teh 3 layers of the filtration membrane? |
|
Definition
1. fenestrated capillary wall (endothelium) of glomerulus - fenestrations and pores
2. Basement membrane of glomerulus - loose meshwork of fibers
3. podocytes (visceral layer of Bowman's capsule) - special epithelial cells that cover the glomerular capillaries; each podocyte contains foot like structures called pedicels; spaces between pedicels are called filtration slits; a slit diaphragm spans the filtration slit |
|
|
Term
| The fenestrated capillary wall prevents filtration of? |
|
Definition
|
|
Term
| The basement membrane prevents filtration of? |
|
Definition
|
|
Term
| The slit diaphragm across filtration slits between podocytes pedicels prevents filtration of? |
|
Definition
|
|
Term
| How is the PCT different from the loop of Henle and DCT? |
|
Definition
| Microvilli on surface of PCT cuboidal epithelial cells increase surface area for reabsorptoin and secretion |
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Term
| What does JGA stand for and where is it located |
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Definition
| Juxtaglomerular apparatus and located mostly in the afferent arteriole ( a little in the efferent arteriole) |
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Term
| Name the 2 types of cell sin the juxtaglomerular apparatus Give a function for each? |
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Definition
1. Macula densa cells - specialized columnar epithelial cells found in the wall of the DCT where the tubule makes contact with the afferent/ efferent arterioles; epithelial cells monitor Na= and Cl- concentration fluid in tubule lumen (filtrate)
2. Granular cells (specialized smooth muscle cells in wall of afferent / efferent arterioles - stimualted by the macula densa to produce renin. |
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Term
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Definition
| catalyzes thechemical reaction that produces Angiotensin I that then is converted to angiotensin II |
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Term
| What structure is responsible for the function of tubuloglomerular feedback? |
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Definition
| Juxtaglomerular apparatus |
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Term
| Name the blood vessels taht supply and drain each glomerulus? |
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Definition
| afferent artiolres supplies; efferent arteriole drains |
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Term
| How is the glomerular capillary bed unlike other capillary beds? |
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Definition
| It is fed and drained by arterioles; regular capillary beds are fed by an arteriole and drained by a venule. |
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Term
| Why is the afferent arteriole typically larger in diameter than the efferent arteriole? |
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Definition
| The efferent arteriole is smaller in diameter than the afferent arteriole; this causes glomerular pressure to be extremely high (important for filtration) Think of a sprayer on the end of a garden hose. The afferent arteriole is the hose. The efferent arteriole is the sprayer ( you can change the size of the hole and thus pressure by rotating the head of the sprayer) |
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Term
| Collecting ducts empty urine into what caup shaped tubes? |
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Definition
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Term
| The effferent arterioles branch around another set of capillaries that wrap around the renal tubules? What are these capillaries called? |
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Definition
| Peritubular capillaires in cortical nephrons and vasa recta in juxtamedullary |
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Term
| What are the 3 main processes of urine formation? |
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Definition
1. Filtration
2. Reabsorption
3 Secretion. |
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Term
| What part of the nephron is responsible for filtration? |
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Definition
| Glomerulus ( and visceral layer of Bowman's capsule) |
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Term
| What parts of the nephron is responsible for reabsorption and secretion? |
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Definition
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Term
| The filter is selective based on what? |
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Definition
| the size of the molecule - not the type of hte molecule |
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Term
| What is one major different between plasma and filtrate? |
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Definition
| Protein concentration; higher protein concentration in plasma (most proteins are too big to be filtered) |
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Term
| Why is it important that most blood proteins not be filtered at the glomerulus? |
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Definition
| If too much solute was filtered, water would follow and too much water would be lost to the urine (in other words you want blood osmotic pressure to be higher tahn the capsular osmotic pressure) |
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Term
| What small protein is filtered by the glomerulus in small amounts? |
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Definition
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Term
| Protein or blood cells in urine indicates a problem with what part of the nephron? |
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Definition
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Term
| Why does "good stuff" end up in the filtrate in the first place? |
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Definition
| The filtration membrane filters by size, not type of molecule; for example, glucose is small enough to pass through the filtration membrane, - In reabsorption we return the good stuff to the blood. |
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Term
| Why doesnt all the bad stuff get filtered at the glomerulus? |
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Definition
Filtration is a passive process; theres only enough time for some of the wastes to be filtered; of the 625 ml of blood that goes to each nephron each minute, only 125 is actually filtered at teh glomerulus; the remaining 500 ml will pass inot the efferent arterioel and then into the peritbular capillaries.
- With Secretion we will take care of the bad stuff that does not make it into the tubule. |
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Term
| What are the 3 pressures controlling Net filtration pressure? |
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Definition
1. Blood Hydrostatic Pressure (BHP)
2. Blood Osmotic Pressure (BOP)
3. Capsular Hydrostatic Pressure (CHP) |
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Term
| Blood Hydrostatic Pressure (BHP) |
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Definition
| - Blood pressure in the glomerulus, promotes filtration - blood pressure generated by left ventricle contraction, forces water and small solutes through the filter and into the Bowman's capsule. Glomerular capillary blood pressure is increased due to the diameter difference in the afferent / efferent arterioles. Hydro = water, hydrosatic pressure is the force a fluid exerts against the walls of the container. |
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Term
| Blood osmotic pressure (BOP) |
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Definition
| opposes filtration - due to pressence of proteins (albumins, globulins, fibrinogen) in blood plasma; the greater the solute concentration, the greater its osmotic pressure; because the plasma has mroe proteins some water moves from the filtrate back into the glomerula rcapillaries. |
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Term
| Capsular Hydrostatic pressure CHP |
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Definition
| opposes filtration - as filtrate is forced into the capsular space between the visceral and parietal wall of the capsule, it meets 2 forms of resistance; the wall of the capsule and the fluid that has alreadyu filled the tubule; as a result, mroe filtrate is pushced back into the glomerular capillaries. |
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Term
| What is the formula for calculating NFP? |
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Definition
| NFP = BHP - (BOP + CHP) normal value for NFP is 10 mm Hg |
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Term
| What happens ot NFP if blood pressure increases? |
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Definition
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Term
| What happens to NFP if blood osmotic pressure decreases? |
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Definition
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Term
| What could cause a lower blood osmotic pressure? |
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Definition
| Loss of protein from the blood |
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Term
| If one were to lose protein would this effect urine volume? |
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Definition
|
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Term
| What is glomerular filtration rate? |
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Definition
125 ml / min
The amount of filtrate formed in all renal corpuscles of both kidneys each minute |
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Term
| What happesn in the reabsorption process if GFR is too high? |
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Definition
| filtrate moving too fast through the tubule; not enough time for reabsorption, results in salty filtrate. |
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Term
| What happens in th ereabsorption process if GFR is too low? |
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Definition
| filtrate moving too slow thorugh tubule; too much time for reabsorptoi; dilute filtrate. |
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Term
| Increasing NFP does what to GFR? |
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Definition
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Term
| What happens to GFR if blood hydrostastic pressure (BHP) drops to 45 mmHg |
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Definition
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Term
| How is GFR regulated intrinsically? what structure? |
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Definition
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Term
| If MAP drops, macula densa cells are stimualated by what mechanism? |
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Definition
low sodium concnetrations (dilute filtrat) and decreases stretch |
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Term
| If MAP drosp what does the macula ddensa do to the efferent or afferent arterioles? |
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Definition
| Vasodilation of afferent arteriole; vasoconstriction of efferent arteriole; increases BHP/NFP/GFR |
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Term
| Wha tturn on the renin/angiotensin mechanism? |
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Definition
| Macula densa activates the granular cells to produce renin; macula densa activated by low sodium concentrations (dilute filtrate) and decreases stretch |
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Term
| What are the four functions of angiotensin II? |
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Definition
1. vasoconstrictor of peripheral arterioles
2. activates thirst center in hypothalamus
3. increases aldosterone productino by adrenal cortex
4. increases ADH production by hypothalamus |
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Term
| Aldosterone is produced by what gland? |
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Definition
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Term
| What is aldosterone's target? |
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Definition
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Term
| What is Aldosterone's actions on the DCT? |
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Definition
| Reabsorb mroe Na+, water follows, so more water is returned to the blood |
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Term
| What is aldosterone's effect on urine volume? |
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Definition
|
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Term
| What is the effect on blood volume? |
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Definition
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Term
| What is the effect on blood pressure? |
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Definition
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Term
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Definition
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Term
| ADH is produced by what gland? |
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Definition
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Term
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Definition
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Term
| What are the 3 targets of ADH and action on each target? |
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Definition
1. tunica media of blood vessels; results in vasoconstrictino (except afferent arteriole)
2. sweat glands 0 turns them off so water is not lost to evaporation
3. targets collecting duct - opens water channels so more water can be reabsorbed and returned it to the blood (facultative water reabsorptoin) |
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Term
| What is the effect of ADH on urine volume? |
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Definition
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Term
| What is the effect of ADH onblood volume? |
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Definition
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Term
| What is the effect of ADH onblood pressure? |
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Definition
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Term
| What is the effect of the Sympathetic division on the autonomic nervous system of GFR? |
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Definition
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Term
| SWhy would you want to reduce blood supply to the kidneys? |
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Definition
| Blood needs to be diverted to skeletal muscles to help you get the heck out of there if you need to |
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Term
| Where in the tubule does most reabsorption take place? |
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Definition
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Term
| Reabsorptoni of what is the key to the transport of almost all other substances? |
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Definition
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Term
| Explain how sodium is reabsorbed and its entry into the peritubular capillaries? |
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Definition
| sodium passively diffuses from filtrate into tubule cells (cuboidal cells ) Na+/K+ pumpts it out of the tubule cells into the interstitial fluid when it can then passively enter the peritublar capillaries |
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Term
| reabsorption of Na promotes reabsorption of water by??? |
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Definition
| osmosis, water follows salt. |
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Term
| How does the reabsorptoin of water lead to the reabsorption of other solutes? |
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Definition
| water movement dilutes solute concnetratoin , so then other soultes follow water; also water is charged and other charged molecules are attracted to it. |
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Term
| The mechanism of solut efollowing solvent is called? |
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Definition
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Term
| The transport of glucose, amno acids, and vitamins si called? |
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Definition
| cotransport = meaning their transport is linked to sodium ions |
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Term
| "Fine tuning" reabsorption takes place in the ??? |
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Definition
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Term
| How is albumin reabsorbed? |
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Definition
| Endocytosis (specifically pinocytosis since the filtrate is a liquid) |
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Term
| What nitrogenous waste is NOT reabsorbed? |
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Definition
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Term
| Describe the reabsorption of HCO3- / H2CO3. How does reabsorbing bicarbonate ions raise blood pH? |
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Definition
| In the filtrate, HCO3- ion scombine with H+ ions secreted by the tubule cells to form H2CO3 (carbonic acid) H2CO3 then forms H20 and CO2 in the filtrate. CO2 diffuses into the tuble cells where it recombines with water to form carbonic acid, which then dissociates into H+ and HCO3-. HCO3- ions then pass out of the tuble cell and into the capillaries. Reabsrobing bicarbonate ions and reutrning them to the blood raises the pH of the blood (HCO3- ions can combine with excess H+ to form carbonic acid) it may appear tha tbicarbone ions are bein reabsorbed and returned directlly to the blood, but there are some chemical reactions that must occur in the tuble cell to get it out of the filtrate and back into the blood. |
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Term
| What determines the transport maximum for absorbed substances? |
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Definition
| The number of carrier proteins |
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Term
| List the 4 major functions of tubular secretions |
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Definition
1. Disposing of any substances taht were not filtered by the glomerulus. such as nitrogenous wastes and certain drugs; reason why some drugs may have to be taken mor ethan once a day.
2. Sometimes undesirable substances such as urea and uric acid are reabsorbed and have to be secreted back into the tubule.
3. Controlling blood pH - when the blood pH is too low (too acidic) H+ are se creted inot the tuble and HCO3- are reabsorbe dfrom the filtrate and reabsorbed to the blood; when blood ph is too high (too alkaline) H+ are reabsorbed fro mthe filtrate and returned to the blood and HCO3- are secreted into the filtrate.
4. Ridding the body of other excess ions (Ca and potassium) |
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Term
| How would tubular srection raise blood pH? |
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Definition
| H+ ions are secreted, HCO3- are reabosrbed |
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Term
Osmolality is similar to ?
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Definition
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Term
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Definition
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Term
| What is the effect of Atrial Natriuretic peptide on the kidney? |
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Definition
| Causes them to secrete (not reabsorb) more salt and therefore more water (increases urine volume, decreaes blood volume, decreaes blood pressure) |
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Term
| ANP is the antagonist of what 2 hormontes? |
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Definition
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Term
| How are urine volume and concentration regulated? |
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Definition
1. Adjust ADH and aldosterone levels
2. Maintain a medullary osmotic gradient (a salty medulla using the countercurrent multiplier mechanism) |
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Term
| The solut eload of the body fluisd is around? |
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Definition
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Term
| Filtrate entering the PCT is what compared to plasma and the surroudning cortex interstitail fluid? |
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Definition
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Term
| The descending limb is impermeable to what and permeable to waht? |
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Definition
| impermeable to salt and permeable to water |
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Term
| The ascending limb is impermeable to what and permeable to what? |
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Definition
| The ascending limb is impermeable to water and premeable to salt |
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Term
| The osmolality of the filtrate in the elbow of the loop of Hnle is about what? |
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Definition
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Term
| The osmolality of the interstitial fluid of the medulla is about what? |
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Definition
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Term
| The osmolalit of the filtrate at the DCT is about what? |
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Definition
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Term
The _______ limb prdocues salty filtrate (so water is returned tothe blood) and the __________ lim buses the high salt concentration to maintain the high osmolality of hte interstitail fuid of the __________
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Definition
The descending limb prdocues salty filtrate (so water is returned tothe
blood) and the ascending lim buses the high salt concentration to
maintain the high osmolality of hte interstitail fuid of the medulla
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Term
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Definition
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Term
| Why do the vasa recta preserve and not destroy the medullary gradient? |
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Definition
| Their walls are very porous so have the same osmolality as the tubule ( water and salt leave and enter the vasa recta as in the tuble) |
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Term
| Ordinary capillaries would absorb massive amounts of what? destroying the medullary gradient? |
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Definition
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Term
| How is dilute urine formed? |
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Definition
| Previously described; kidneys allow hypoosmotic filtrate coming out of the DCT to continue out of the collecting ducts, calyces pelvis and urter, no adjustments need to be made in the collecting duct |
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Term
| Urine is concnetrated where? under what influence? |
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Definition
| Urine is concentrated in the collecitn ducts and under the influence of ADH |
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Term
| Because water reabsorption depends on the presence of ADH this mechanism is called? |
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Definition
| facultative water reabsorption |
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Term
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Definition
| Renal clearance is the volume of plasma cleared of a substance in one minute |
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Term
| Why are some drugs / toxins cleared from the blood more rapidly than woudl be possibe by just glomerular filtration? |
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Definition
| Due to secretion (excretion for theses drugs woudl equal filtration + secretion) |
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Term
| What protein carriers secrete thses drugs /toxins into the filtrate? |
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Definition
| Organic anion transporters (OATS) |
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Term
| They are able to acomplish this because they are |
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Definition
| polyspecific (they can transport mroe than one kind of molecule) |
|
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Term
| What is inulin and why is it used to calculate GFR? |
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Definition
| Inulin is a plant compound tha tis only filtered (no reabsorption nor secretion |
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Term
| Why is creatinine RC used more often than inulin to calculate GFR |
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Definition
| It is naturally found in the blood and does not ahve to be infused into the patient as with inulin |
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Term
| Why is thi smethod not as precise as the inulin method? |
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Definition
| It is secreted in small amounts |
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Term
| Abnormal decreases in GFR would do what to plasma creatinen levels? |
|
Definition
| increase plasma creatinine levels. |
|
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Term
| What effects does an increase in plasma creatinine levels have on RC of creatinine? |
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Definition
| RC would decrease (remember RC = the amount fo blood cleared in a minute; in this case less blood would be cleared of creatinin per minute b/c GFR is too low or too slow |
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Term
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Definition
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