Exam 4 Human Physiology _ Cheng

Set to 'answer with term'. When question has ( / ) brackets, answer with the correct term from the brackets. Lmk if there's any errors. Topics that aren't covered: nephron anatomy, tubuloglomerular feedback pathway, mechanisms of Na+, glucose, and organic anion transports,

Breathing in oxygen from the environment

What is the first step of respiration?

Oxygen diffuses from the aveoli to the bloodstream

What is the second step of respiration?

Transport of oxygen through the bloodstream

What is the third step of respiration?

Perfusion of oxygen from the bloodstream into tissues

What is the fourth step of respiration?

Simple diffusion

What process moves gas from the aveoli to the bloodstream?

160 mmHg

What is the PO2 of oxygen in the atmosphere?

100 mmHg

What is the PO2 of oxygen in the aveoli?

40 mmHg

What is the PO2 of oxygen in the tissues?

40 mmHg

What is the PCO2 of CO2 in the aveoli?

46 mmHg

What is the PCO2 of CO2 in the tissues?

distance and surface area

A single layer of cells divides the capillaries and aveoli, allowing simple diffusion. With this in mind, what two variables of simple diffusion are we MOST concerned about that would cause hypoxias?

Emphysema

Which lung pathology is this: destruction of aveoli means less surface area for gas exchange?

Fibrotic lung disease

What lung pathology is this: thickened alveolar membrane slows gas exchange. Loss of lung compliance may decrease aveolar ventilation.

Pulmonary edema

What lung pathology is this: fluid in the interstitial space increases diffusion distance. Arterial CO2 may be normal due to higher CO2 solubility in water.

Asthma

What lung pathology is this: increased airway resistance due to bronchiole constriction decreases alveolar ventilation.

emphysemia and fibrotic lung disease

Which hypoxia pathology or pathologies is/are described by normal/low PO2 in the aveoli, and low PO2 in the bloodstream?

Pulmonary edema

Which hypoxia pathology or pathologies is/are described by normal PO2 in the aveoli, and low PO2 in the bloodstream?

Asthma

Which hypoxia pathology or pathologies is/are described by low PO2 in the aveoli, and low O2 in the bloodstream?

The third step

Anemia affects which step of the respiratory pathway?

The fourth step

Diabetes affects what step of the respiratory pathway are you affecting?

The first step

Asthma, lung blockage, and emphysema affects what step of the respiratory pathway?

the second step

Fibrotic lung disease and pulmonary edema all affect what step of the respiratory pathway?

Obstructive

What term describes increased airway resistance for exhalation?

Restrictive

What term describes reduced lung compliance?

altitude and humidity

What is atmospheric O2 affected by?

Lung compliance and airway resistance

What is alveolar O2 affected by?

surface area and distance

What is plasma O2 affected by?

Alveolar ventilation

What are these factors of: rate and depth of breathing, airway resistance, and lung compliance

Diffusion distance

What are these factors of: barrier thickness and amount of fluid

O2 reaching the alveoli

What are these factors of: composition of inspired air and aveolar ventilation

Alveolar gas exchange

What are these factors of: O2 reaching the alveoli, gas diffusion between aveoli and blood, and adequate perfusion of aveoli

hemoglobin

Oxygen is not very soluble in water. What do we use to move oxygen through the bloodstream?

concentration (pressure)

O2 movement is driven by what?

plasma PO2 + HbO2

What is the formula for hemocrit?… Total blood O2 =

70%

What percentage of CO2 in the body is fixated into bicarbonate?

bicarbonate

What works as a buffer to maintain pH level in the body?

Chloride shift

How does bicarbonate leave the red blood cell to enter the plasma, or leave the plasma to enter the red blood cell?

23%

What percentage of CO2 in the body is bound to hemoglobin?

7%

What percentage of CO2 in the body is dissolved into the blood?

4

How many binding sites, on average, does hemoglobin have?

Plasma O2 and the amount of hemoglobin

The amount of oxygen bound to hemoglobin depends on which two factors?

the percent saturation of hemoglobin

In regards to hemoglobin, Plasma O2 will determine what?

Hb content per RBC

The amount of hemoglobin you have decides how many total hemoglobin binding sites you have. This is calcuated by Hb content per RBC and the number of RBC you have. Which of these is a genetic factor?

increases

When PO2 is high, the binding affinity of O2 for hemoglobin (increases/decreases).

decreases

When PO2 is low, the binding affinity of O2 for hemoglobin (increases/decreases).

Right

A (right/left) shift in a HbO2 saturation curve will cause more O2 to be released to the tissue.

CO2, temperature, 2,3-DPG, and [H+]

What are the factors, when INCREASED, that will cause a right shift in the HbO2 saturation curve?

left

A (right/left) shift in a HbO2 saturation curve will cause more O2 to be bound, but less O2 to be released.

carbon monoxide poisoning

What causes an extreme right shift in the HbO2% saturation curve, all while the body does nothing to counteract it?

Step 3

What step of respiration does carbon monoxide interfere with?

increased red blood cell synthesis

While at high altitudes, the body is deprived of adequate oxygen, thus suffering hypoxia. What acclimization may occur after days or weeks?

true

True/false: breathing is controlled both autonomically and voluntarily

Inspiration somatic motor neurons

The scalene and sternocleidomastoid muscles, the external intercostals, and the diaphragm respond to signals carried by…

Expiration somatic motor neurons

The internal intercostals and abdominal muscles are controlled by…

medullary chemoreceptors

CO2 is picked up by _______ ___________, which sends signals to the medulla oblongata and pons for respiration control.

CO2, O2, pH

Carotid and aortic chemoreceptors detect ___, ___, and ___, and send signals through afferent sensory neurons to the medulla oblongata and pons.

emotions and voluntary control

What is processed by higher brain centers, then the limbic system, and then the medulla oblongata for respiratory response?

Medulla oblongata and pons

Which brain areas is the respiratory control center located in?

initiating

The medulla oblongata is responsible for (initiating/modulating) respiration.

modulating

Pons is responsible for (initiating/modulating) respiration.

pre-botzinger complex

What is located in the medulla oblongata and is the respiratory pacemaker that slowly fires to keep you breathing subconsciously?

Dorsal Resp Group

What is located in the medulla oblongata and is responsible for output to inspiratory muscles?

Ventral resp group

What is located in the medulla oblongata and is responsible for output to the expiratory muscles?

Pons

The (medulla oblongata/pons) is responsible for receiving and acting upon emotional output from higher brain centers. It is also the place where most sleep apnea occurs in.

CO2 and H+

Medullary chemoreceptors detect which two things the best?

blood brain barrier

What is the highly selective membrane around the brain?

high CO2

There is a reflex that orchestrates when chemoreceptors detect a (high/low) level of ___, the respiratory control centers send an involuntary signal to breathe.

renin

What hormone does the kidney produce, thereby making it an endocrine gland?

glycogen, glucose

The kidney stores _____, and converts it to _____.

volume, osmolarity, pH

What three things does the kidney exert homeostatic control over?

kidney, ureter, bladder, urethra

Trace the pathway of the urinary (renal) system, placing commas between parts.

Outer cortex

The part of the kidney that holds the afferent arterioles and glomeruli.

Inner Medulla

The part of the kidney that holds loops of Henle, collecting ducts, and vasa recta.

Renal arteries

The blood vessels that carry dirty blood towards the cortex of the kidney.

Renal veins

The blood vessels that carry clean blood away from the cortex of the kidney.

Vasa recta

These vessels around the nephron are highly permeable to water and solutes, allowing passive, rapid diffusion of substances in and out of the blood.

portal system

a specialized part of the circulatory system where blood passes through two consecutive capillary networks, rather than one, before returning to the heart

Glomerulus

Where is the first capillary bed in the renal portal system?

Peritubular capillaries

Where is the second capillary bed in the renal portal system?

Glomerulus

The tiny, specialized network of capillaries surrounded by the bowman’s capsule, located inside each nephron of the kidney that acts as the primary filtering unit of blood.

Bowman’s capsule

a cup-shaped, double-walled epithelial sac at the start of the nephron in the kidney cortex that surrounds the glomerulus

80, 20

The first ___% of the nephron is unregulated. The second ___% is regulated.

Filtration

What describes the nonselective movement of plasma water and solute from the glomerulus into the bowman’s capsule?

Reabsorption

What describes the selective movement from the kidney lumen to the blood?

secretion

What describes the selective movement from the blood of the peritubule capillaries to the kidney lumen? This can increase the excretion of x beyond what was filtered in.

execretion

What describes the movement of kidney lumen into an external environment?

filtered - reabsorbed + secreted

What is the formula to determine the amount of solute excreted?

glucose

What is 100% reabsorbed until a condition like diabetes is present?

podocytes

What surrounds each capillary and leave slits through which filtration takes place? These serve the purpose of limiting the size of the molecule that can be filtered. They’re also known as ‘Bowman’s capsule epithelium’.

negative

The basal lamina (or basement membrane) of the kidney has a (positive/negative) charge, which prevents molecules of the same charge from filtering in.

glomerus hydrostatic pressure

Represented by P_H, this is the pressure that works in favor of filtration.

pi

What represents the colloid osmotic pressure gradient due to proteins in the plasma but not in the Bowman’s capsule? This pressure also works against filtration.

Pfluid

What represents the fluid pressure created by fluid in the Bowman’s capsule? This pressure also works against filtration.

Glomerular filtration rate

What is the term that describes volume of plasma water filtered per time? (Average is 125 mL/min or 180L/day). It’s also used as an assay of kidney function.

GFR / renal plasma flow

How do you find the filtration fraction?

20, 1

Only ___% of the plasma that passes through the glomerulus is filtered. Less than __% of filtered fluid is eventually execreted.

Vasoconstriction of the afferent arteriole

This is the main way of regulating the glomerulus filtration rate when it’s too high. Doing this action increases resistance and decreases renal blood flow, capillary blood pressure, and glomerulus filtration rate.

Vasodilation of the afferent arteriole

This is the main way of regulating glomerulus filtration rate when it’s too low. Doing this action decreases resistance, and increases renal blood flow, capillary blood pressure, and glomerulus filtration rate.

80, 180

Autoregulation maintains a nearby constant GFR when arterial blood pressure is between ___ and ___ mmHg.

myogenic response and tubuloglomerular feedback

What are the two local control options of regulating the GFR at the afferent arteriole?