Module 5: Gas Exchanges Flashcards
When inhaled, the diaphragm and rip muscles are
contracts to increase the volume of the lungs
When inhaled, the diaphragm and rip muscles are
contract to increase the volume of the lung
Gas exchange occurs _____ in the lungs
Alveolus. Each Alveolus is surrounded by capillaries. Oxygen diffuses from the alveolus to the blood, and Co2 diffuses from the blood to the alveolus, and it becomes rich in oxygen
Gas exchange occurs across specialised respiratory surfaces by
passive diffusion
=> gas itself cannot get across the cell membrane
Gas exchange: Partial pressures of gases
the pressure excerted by particular gas in a mixture of gases
Quiz II - Organisms in which a circulating body fluid is distinct from the fluid that directly surrounds the body’s cells are likely to have which of the following?
a closed circulatory system
A human red blood cell in an artery of the left arm is on its way to deliver oxygen to a cell in the thumb. From this point in the artery, how many capillary beds must this red blood cell pass through before it returns to the left ventricle of the heart?
two
What is the function of a circulatory system?
It brings a transport liquid into close contact with all cells in the body.
=> This transport liquid exchanges gases, nutrients, and wastes with the cells in the body.
voice sounds are produced by the ____
larynx
the primary functions of the ____ are to warm, filter, and humidify air
nasal cavity
Why do the circulatory systems of land vertebrates have separate circuits to the lungs and to the rest of the body?
The large decrease in blood pressure as blood moves through the lungs may prevent efficient circulation through the rest of the body.
=> The changes in blood pressure as blood moves through the lungs of land-dwelling vertebrates make it necessary to have separate circuits to the lungs and the rest of the body.
True or false? The circulatory systems of land-dwelling vertebrates are composed of two pumping circuits: the systemic circulation, which is a lower-pressure circuit to the lung, and the pulmonary circulation, which is a higher-pressure circuit to the rest of the body.
F
=> The pulmonary circulation is the lower-pressure circuit to the lung, whereas the systemic circulation is the higher-pressure circuit to the rest of the body.
in negative pressure breathing, inhalation results from
contracting diaphragm
What is the function of the left ventricle?
It pumps oxygenated blood around the body via the systemic circulation.
Which of the following statements about blood circulation in the body is true?
Valves are flaps of tissue that close when the ventricles contract to prevent the backflow of blood into the atria and also when the ventricles relax to prevent the backflow of blood from exiting vessels to the ventricles.
Which event occurs first during atrial and ventricular diastole?
The atria and ventricles are relaxed, and blood flows into the atria.
=> Diastole is the relaxation phase of the cardiac cycle during which the chambers of the heart are relaxed and blood can enter them passively.
when you hold your breath, which of the following blood gas changes first leads to the urge to breathe?
A) rising CO2
B) rising O2
C) falling CO2
D) rising CO2 and falling O2
E) falling O2
A
Which event of the cardiac cycle occurs when systolic blood pressure is measured?
The ventricles contract, carrying blood into the aorta, and blood flows into the relaxed atria.
=> The systolic blood pressure is the peak blood pressure, resulting from contraction of the ventricles.
If the atrioventricular node could be surgically removed from the heart without disrupting signal transmission to the Purkinje fibres, what would be the effect?
Atria and ventricles would contract at about the same time.
Average blood pressure is lowest in which structure(s)?
venae cavae
Which of the following is correct for a blood pressure reading of 130/80?
I. The systolic pressure is 130.
II. The diastolic pressure is 80.
III. The blood pressure during heart contraction is 80.
I and II only
What is the reason that fluid is forced from the bloodstream to the surrounding tissues at the arteriole end of systemic capillaries?
The hydrostatic pressure of the blood is greater than the osmotic pressure of the blood.
What would be the long-term effect if the lymphatic vessels associated with a capillary bed were to become blocked?
Fluid would accumulate in interstitial areas.
Human plasma proteins include which of the following?
Immunoglobulin, fibrinogen
Which of these speed up heart rate?
epinephrine (adrenaline)
Which of the following is a normal event in the process of blood clotting?
activation of prothrombin to thrombin
The average resting stroke volume of the heart is 70 mL and it beats ~72 times per minute. This would result in which cardiac output?
To calculate the cardiac output, you need to multiply the stroke volume (SV) by the heart rate (HR). In this case, the stroke volume is given as 70 mL, and the heart rate is approximately 72 beats per minute.
Cardiac Output = Stroke Volume × Heart Rate
Cardiac Output = 70 mL/beat × 72 beats/minute
Cardiac Output = 5040 mL/minute
The cardiac output would be 5040 mL/minute.
5L/min
Which sequence of blood flow can be observed in either a reptile or a mammal?
vena cava→right atrium→ventricle→pulmonary circuit
Which of these are involved in the early stages of blood clotting?
platelets
Voice sounds are produced by the _____.
larynx
The primary functions of the _____ are to warm, filter, and humidify air.
nasal cavity
Why is gas exchange more difficult for aquatic animals with gills than for terrestrial animals with lungs?
Water contains much less O2 than air per unit volume.
Which of the following is an example of countercurrent exchange?
the flow of water across the gills of a fish and that of blood within those gills
Atmospheric pressure at sea level is equal to a column of 760 mm Hg.
Oxygen makes up 21% of the atmosphere by volume.
21/100 x 760 = 160 mmHg
Which of the following occurs with the exhalation of air from human lungs?
The volume of the thoracic cavity decreases.
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.
Tidal volume in respiration is analogous to what measurement in cardiac physiology?
stroke volume
Which of the following occurs with the exhalation of air from human lungs?
The volume of the thoracic cavity decreases
A person with a tidal volume of 450 mL, a vital capacity of 4,000 mL, and a residual volume of 1,000 mL would have a potential total lung capacity of
To calculate the potential total lung capacity, we can sum up the vital capacity and the residual volume.
Given:
Tidal volume = 450 mL
Vital capacity = 4,000 mL
Residual volume = 1,000 mL
Total Lung Capacity = Vital Capacity + Residual Volume
Total Lung Capacity = 4,000 mL + 1,000 mL
Total Lung Capacity = 5,000 mL
Therefore, the potential total lung capacity would be 5,000 mL.
The Bohr shift on the oxygen-haemoglobin dissociation curve is produced by changes in
pH
Hydrogen ions produced in human red blood cells are prevented from significantly lowering pH by combining with
Haemoglobin.
