respiratory system review
Calculate the partial pressure of O2 on the top of Mt. Whitney. ______mmHg
(20.9•440)÷100= 92 mmHg
What modifies this medullary center?
-CENTRAL CHEMORECEPTORS -PERIPHERAL CHEMORECEPTORS -PONS
Name four of the six factors that probably increase ventilation during exercise.
1- LEARNED RESPONSES 2- NEURAL IMPUT FROM THE MOTOR CORTEX 3- RECEPTORS IN MUSCLE & JOINTS 4- INCREASED BODY TEMP
Each hemoglobin molecule consists of:
1. A globin portion composed of 4 polypeptide chains. 2. Four iron-containing pigments called heme groups.
These gases are carried in several different forms:
1. dissolved in the plasma 2. chemically combined with hemoglobin 3. converted into a different molecule
Factors which alter hemoglobin saturation:
1. pH 2. temperature 3. PCO2 4. BPG (2,3-biphosphoglycerate)
What is the atmospheric pressure on the top of Mt. Whitney? ___________
440mmHg
Arterial Po2 must drop below what to stimulate the peripheral chemoreceptors? _____________
60 MMHG
Dust, smoke, and noxious fumes will stimulate receptors in airways. a. Name the receptors. _________________________ b. Explain the protective reflexes.
A) IRRITANT RECEPTORS- PERIPHERAL CHEMORECEPTORS B) COUGH OR SNEEZE
a. What does lung hyperinflation stimulate? _________________________ b. The effect on inspiration is _________________________. c. What is this reflex called? _________________________
A) PULMONARY STRETCH RECEPTORS IN VISCERAL PLEURA B) SENDS INHIBITORY SIGNALS TO PROTECT AGAINST OVER STRETCH C) HERING BREUER REFLEX
When the pH decreases, carbon dioxide loading facilitates oxygen unloading. The interaction between hemoglobin's affinity for oxygen and its affinity for hydrogen ions is called the
Bohr effect
a. The relationship between pressure and volume is known as _________ Law.
Boyle's Law
What is the most important stimulus controlling ventilation? ___________
CO2
Name two other important factors that play roles in ventilation:
Resistance and pressure gradient
a. When the bronchiole constricts, what will happen to resistance? ____ (use arrows) b. To airflow? ____ (use arrows)
Resistance will increase and airflow will decrease
a. If transpulmonary pressure equals zero, what will happen to the lungs? ______________________ b. This is known as a _____________________.
The lungs would not inflate and there would be no exchanging of gases
When one oxygen binds to hemoglobin, the other oxygen molecules bind more readily
This is called cooperative binding. Hemoglobin's affinity for oxygen increases as its saturation increases.
Oxygen loading facilitates carbon dioxide unloading from hemoglobin
This is known as the Haldane effect
Where in the medulla are the neurons that set the basic respiratory rhythm? _______________
VRG
Transport of oxygen during external respiration:
With its low solubility, only approximately 1.5% of the oxygen is transported dissolved in plasma.
a. Why does more CO2 than O2 dissolve in liquid when both gases are at the same pressure? b. Name the law that explains this. _____________________
a. CO2 is more soluble in liquid than O2 b. Name the law that explains this phenomena: Henry's Law
a. What pressure is always negative and helps to keep the lungs inflated? ______________________ pressure b. It is most negative during _____________________.
a. Intrapleural Pressure b. Inspiration
The atmosphere is a mixture of gases. Write down the percentages for: a. O2 ___________ b. CO2 ___________ c. N2 ___________ d. H2O ___________
a. O2 20.9% b. CO2 0.04% c. N2 78.6% d. H2O 0.46%
If a person hyperventilates what will happen to the following in the blood? a. Pco2 _____________ b. pH _____________
a. Pco2 = DECREASE b. pH = INCREASE RESPIRATORY ACIDOSIS
If a person hypoventilates what will happen to the following in the blood? a. Po2 _____________ b. Pco2 _____________
a. Po2 = DECREASE b. Pco2 = INCREASE RESPIRATORY ALKALOSIS
The planet Pneumo has a total atmospheric pressure of 900 mmHg. Oxygen and carbon dioxide each constitute 30% of the atmosphere. a. What is the partial pressure of oxygen on the planet Pneumo? ________ b. Which gas would be found in the highest concentration in your blood?
a. What is the partial pressure of O2 on the planet Pneumo? (900•30)÷100= 270mmHg b. Which gas would be found in the highest concentrations in your blood? CO2
When airflow is restricted so that the partial pressure of O2 is low and CO2 is high, what happens to the: a. arterioles? ________________ b. bronchioles? ________________
a. arterioles: vasoconstriction (CO2 effect) b. bronchioles: dilation (O2 effect)
Internal respiration depends on three factors - list them.
a. available surface area b. partial pressure gradients c. variable rate of blood flow varies
What three factors cause the partial pressures of gases in the alveoli to differ from pressures in the atmosphere?
a. humidification of the air b. gas exchange between capillaries and alveoli c. making of old and new air
Efficient external respiration depends on three main factors - list them.
a. surface areas and structure of the respiratory membrane b. partial pressure gradients c. matching alveolar air flow to pulmonary capillary blood flow
Histamine will ____________ bronchioles → ____ resistance →____ airflow
constrict, resistance goes up and airflow goes down
A decrease in surfactant will result in a ____ (↑ or ↓) in compliance.
decrease
Fibrosis will (↑ or ↓) ___ compliance making it __________ to inflate the lungs.
decrease, harder
Intrapulmonary pressure ____s (↑ or ↓) during inspiration.
decreases
Epinephrine will ____________ bronchioles → ____ resistance → ____ airflow
dilate, down because it dilates bronchioles
Each hemoglobin molecule can transport up to 4 oxygen molecules because
each iron atom can bind one oxygen molecule.
What ion directly stimulates the central chemoreceptors? _____________
hydrogen
When hemoglobin binds with oxygen, it is called
oxyhemoglobin
Oxygen binding occurs in response to
the high partial pressure of oxygen in the lungs.
The blood transports oxygen and carbon dioxide between
the lungs and other tissues throughout the body.
The degree of hemoglobin saturation is determined by
the partial pressure of oxygen, which varies in different organs throughout the body.
Carbon dioxide transport:
• Carbon dioxide is produced by cells throughout the body. • It diffuses out of the cells and into the systemic capillaries, where approximately 7% is transported dissolved in plasma. • The remaining carbon dioxide diffuses into the red blood cells. Within the red blood cells, approximately 23% chemically combines with hemoglobin, and 70% is converted to bicarbonate ions, which are then transported in the plasma.
The oxygen saturation of hemoglobin is affected by:
• PO2 • pH • temperature • PCO2, and • BPG
Carbon dioxide is transported in three ways:
• dissolved in plasma • bound to hemoglobin as carbaminohemoglobin, and • converted to bicarbonate ions
Oxygen is transported in two ways:
• dissolved in plasma, and • bound to hemoglobin as oxyhemoglobin