Respiratory System Flashcards
How carbon dioxide leaves the body.
5 steps
- CO2 is released from the mitochondria
- CO2 diffuses into a capillary
- CO2 is carried ito the lungs
- Co2 diffuses into an alveolus
- Air exits through nose or mouth.
Key events of Gas Exchange.
- Breathing moves air in and out of the______
- O2 diffuses from _____ in the lungs into _____
- O2 enters _______, where it binds to the protein ________
- O2 diffuses from the blood to the body’s tissues, and carbon dioxide diffuses from the tissues to the blood
- CO2 leaves the body when we exhale
lungs
alveoli…capillaries
red blood cells…hemoglobin
The path oxygen follows from the lungs to the body tissues.
- Oxygen diffuses from the _________ into surrounding ________.
- O2 enters a _________
- O2 binds to a molecule of ___________
- O2 is carried through blood vessels to a _________
- O2 diffuses from the blood to the ___________
alveoli ...capillaries red blood cell hemoglobin capillary body tissues
The path of air into lungs
- Air enters through the nose or mouth
- Air travels down the ________ and then enters the _______
- Air travels down smaller and smaller __________.
- Air reaches small sacs called _________
trachea…bronchi
bronchioles
alveoli.
Mechanics of Breathing: INHALATION
- Air enters body
- Rib muscles contract
- Diaphragm contracts (moves down).
Mechanics of Breathing: EXHALATION
- Air leaves body
- Rib muscles relax
- Diaphragm relaxes (moves up).
The interface between the air and the blood is composed of ________, __________ and _________.
the epithelial cells of the alveolus, the extracellular fluid, and the capillary wall
The interface between the air and the blood is composed of the epithelial cells of the alveolus, the extracellular fluid, and the capillary wall.
Which of the following statements about oxygen transport is FALSE?
a. Oxygen moves according to the principles of diffusion.
b. Most oxygen binds to hemoglobin, but some is free in the plasma.
c. Under normal circumstances, about 50% of the oxygen is unloaded at the cellular level.
d. When one oxygen binds to hemoglobin, the shape is changed and three more oxygens can bind rapidly.
c. Under normal circumstances, about 50% of the oxygen is unloaded at the cellular level.
This is a false statement. Usually about 30% of the oxygen is unloaded. With strenuous activity, unloading can increase to about 60%.
An increase in hydrogen ions will decrease the___of the blood.
Carbon dioxide is converted to ________ with the help of carbonic anhydrase.
The ____carries the carbon dioxide back to the lungs.
Carbon dioxide moves according to the principles of _____.
Carbonic acid dissociates, releasing a ______ ion and a _______ ion
pH…carbonic acid… blood … diffusion…bicarbonate…hydrogen
Hemoglobin acts as a buffer because ________ released by the dissociation of ________ bind to ________ preventing large swings in ________ .
protons …. carbonic acid… hemoglobin,… blood pH
By definition a buffer acts to maintain a relatively constant pH.
True or false. When discussing breathing, we can say that air enters the lungs because the diaphragm contracts and in the process, oxygen passes into the alveoli and then down its concentration gradient from an alveolus to the blood. When we breathe out, the diaphragm relaxes and carbon dioxide passes down its concentration gradient from the blood to the alveolus and then out of the lungs.
True.
This is a true statement. This is what happens when we breathe.
Boyle’s Law describes how air moves into and out of the lungs during inspiration and expiration. By changing the _______ of the thoracic cavity, the pressure changes in the _______ . _______ volume of the thoracic cavity leads to a _______ pressure, causing air to flow into the lungs (down its pressure gradient) and thus causing inspiration.
volume…lungs
Increasing…decreased
Which muscles, when contracted, would increase the volume of air in the thoracic cavity?
diaphragm and external intercostals
Yes, contraction of both the diaphragm (the diaphragm flattens) and the external intercostals (pulls the ribs up and out) will increase the volume of the thoracic cavity. This will cause air to move into the lungs (inspiration).
Which pressure is the result of the natural tendency of the lungs to decrease their size (because of elasticity) and the opposing tendency of the thoracic wall to pull outward and enlarge the lungs?
intrapleural pressure
Yes, the lungs tend to decrease their size while the chest wall tends to pull the thorax outward. This makes the intrapleural pressure more negative than the other two pressures (described as subatmospheric), thus keeping the lungs inflated.
During an allergic reaction, there is increased resistance in the bronchioles and __________ dilates the bronchioles, thus making it easier to breathe.
__________ is released from the adrenal gland during stressful situations.
Epinephrine
People with severe allergies carry an EpiPen in case the allergic reaction produces anaphylaxis.
If the transpulmonary pressure equals zero, what will happen to the lung?
lungs will collapse
Yes, the transpulmonary pressure creates the suction that keeps the lungs inflated. When room air enters the pleural space, transpulmonary pressure is zero and the lungs deflate – this is known as a pneumothorax.
Most carbon dioxide is carried from the body tissues to the lungs as _____.
bicarbonate ions (HCO3-)
Most carbon dioxide released from body tissues combines with water to form carbonic acid, which then breaks up into hydrogen and bicarbonate ions.
By picking up hydrogen ions, hemoglobin prevents the blood from becoming too _____.
acidic
If not carried by hemoglobin, hydrogen ions would reduce the pH, or increase the acidity, of the blood.
In the blood most of the oxygen that will be used in cellular respiration is carried from the lungs to the body tissues combined with _____.
hemoglobin
In the blood most oxygen is transported attached to hemoglobin.
During inhalation,
a. the volume of the thoracic cavity decreases.
b. the diaphragm and rib muscles contract.
c. air moves up the trachea.
d. oxygen molecules move into the lungs, and carbon dioxide molecules move out of the lungs.
e. the diaphragm relaxes.
b. the diaphragm and rib muscles contract.
The contraction of these muscles causes air to enter the lungs.
From which structures do oxygen molecules move from the lungs to the blood?
Alveoli
Alveoli are tiny sacs in the lungs surrounded by capillaries. The alveoli are where oxygen diffuses from the lungs to the blood.
Which statement is correct?
a. In the blood, oxygen is bound to hemoglobin, a protein found in red blood cells.
b. As oxygen diffuses from the lungs into capillaries, blood becomes deoxygenated.
c. Oxygen is released from the mitochondria as a product of cellular respiration.
d. Carbon dioxide diffuses from the alveoli into surrounding capillaries.
e. Oxygen diffuses from large blood vessels into the body’s cells.
a. In the blood, oxygen is bound to hemoglobin, a protein found in red blood cells.
When oxygen diffuses from the alveoli to the surrounding capillaries, it enters a red blood cell and binds to hemoglobin.
After blood becomes oxygenated, it returns to the _______ and is then pumped to _______ .
heart, … body cells
Hemoglobin is a _______ that can bind four molecules of _____.
protein…oxygen.
