Chapter 23 - The Respiratory System - Part 4 Flashcards
do red blood cells have mitochondria?
no
since red blood cells do not have mitochondria, how do they produce their ATP?
through glycolysis
BPG (2,3-bisphosphoglycerate) is generated through glycolysis. This compound has a ____ effect on oxygen binding
DIRECT EFFECT
The higher the concentration of BPG, the ____ the release of oxygen by heme molecules
greater
BPG levels ____ when the pH increases and the Bohr effect appears when the pH _____
BPG levels INCREASE when the pH increases and the Bohr effect appears when the pH DECREASES
When plasma pO2 levels are low for an extended period of time, red blood cells will….
generate MORE BPG because the more BPG, the more oxygen that hemoglobin releases
The Red Blood Cells of a developing fetus contain ___ hemoglobin
fetal
fetal hemoglobin is different from adult hemoglobin in that….
it has a higher affinity for oxygen
Name 3 ways in which carbon dioxide is transported in the blood
- converted to a molecule of carbonic acid
- binds to hemoglobin within red blood cells
- dissolves in plasma
How is MOST CO2 transported in the blood?
as carbonic acid (bicarbonate ions) roughly 70%
When carbon binds to hemoglobin (to exposed amino groups) what is the name of the compound that results?
carbaminohemoglobin
Does plasma become saturated with carbon dioxide quickly or slowly?
quite rapidly
a bicarbonate moves out of the red blood cell in exchange for a…..
chloride ion (chloride shift)
Identify the 3 ways that carbon dioxide is transported in the bloodstream
- as carbonic acid
- dissolved in plasma
- binds to hemoglobin
As you exercise, hemoglobin releases more oxygen to active skeletal muscles than it does when those muscles are at rest. Why?
The combination of increased temperature and lower pH (from heat and acidic waste generated by active skeletal muscles) causes hemoglobin to release more oxygen then when the body is at rest
How would blockage of the trachea affect blood pH?
Blockage of the trachea would interfere with the body’s ability to gain oxygen and eliminate carbon dioxide. Because most carbon dioxide is transported in the blood as bicarbonate ions formed by the dissociation of carbonic acid, an inability to eliminate carbon dioxide would result in an excess of hydrogen ions, which LOWERS BLOOD PH
Equilibrium must exist between peripheral cells and…..
alveolar capillaries
if diffusion rates at the peripheral and alveolar capillaries become unbalanced, name the TWO homeostatic mechanisms involved to restore equilibrium
- changes in blood flow and oxygen delivery that are regulated at the local level
- changes in the depth and rate of respiration under control of the brain’s respiratory receptors
The activities of the respiratory centers of the brain are coordinated with what?
changes in cardiovascular function, such as blood pressure and cardiac output
In a tissue that becomes more active, more O2 is delivered and more CO2 is carried away. the rising pCO2 levels causes what?
the relaxation of smooth muscles in the walls of arterioles and capillaries in the area, causing an increase in blood flow
At the lungs, local factors coordinate which 2 things?
-lung perfusion (blood flow to the alveoli)
-alveolar ventilation (airflow)
As blood flows towards the alveolar capillaries, it is directed towards lobules with a relatively ___ Po2
high
When the PCO2 goes up, bronchioles ___ in diameter
increase
respiratory control has both __ and __ components
voluntary and involuntary
Your brains’ INVOLUNTARY centers regulate the activities of what??
the respiratory muscles. Adjust the frequency and depth of pulmonary ventilation
The VOLUNTARY control of respiration reflects activity in the….
cerebral cortex
What are the “respiratory centers”?
3 pairs of nuclei in the reticular formation of the medulla oblongata and pons
What centers set the pace (rhythm) for respiration?
the “respiratory rhythmicity centers” of the medulla oblangata
-divided into dorsal respiratory group and ventral respiratory group
does the dorsal or ventral respiratory group function in EVERY respiratory cycle, whether quiet or forced?
dorsal respiratory group (has the inspiratory center)
The DRG’s inspiratory center innervates what?
the motor neurons that innervate the external intercostal muscles and the diaphragm
When does the VENTRAL respiratory group function?
only during forced breathing
The VRG has a ___ center
expiratory (and inspiratory)
the expiratory center of the VRG consists of neurons that innervate….
accessory respiratory muscles involved in active exhalation
the inspiratory center of the VRG contains neurons involved in….
maximal inhalation