Ventilation and Circulation Flashcards
What are the two actions necessary for gas exchange to take place?
Respiration = gas exchange
Ventilation = moving air in and out of the lungs
What are the two types of afferent input that control the ventilation?
Afferent input (the signal) to the brain may be
- neural (passed to the brain by the nerves)
- humoral (the signal travels in the blood, i.e. co2 levels)
Ventricular relaxation immediately follows ________.
A) atrial depolarization
B) ventricular repolarization
C) ventricular depolarization
D) atrial repolarization
B) ventricular repolarization
The cardiovascular centers are located in which area of the brain?
A) medulla oblongata
B) pons
C) mesencephalon (midbrain)
D) cerebrum
A) medulla oblongata
Why do we have these two pleural layers?
What is the role of the sac?
The two layers create a sac around the lung: pleural sac filled with pleural fluid
Allows:
- Movement of the lungs in the rib cage
- Allows the lung to expand with very little friction
Pleural sac creates a pressure gradient around the lung
Define External Respiration
Delivery of O2 from the air to tissues
and removal of CO2 from tissues into the air
What causes expiration to stop at maximum expiration
Chest wall compliance reaches limit
What are the primary and accessory muscles responsible for inspiration?
Primary :
- Diaphragm
- External intercostals
Accessory :
- Scalenes
- Pecs (Major and minor)
- Lat dorsi
- Serratus anterior
- Trapezius
- Sternocleidomastoid
- Erector spinae
- Abdominals - critical muscles in inspiration!
4 components of the upper respiratory tract and the function of each component
- Nose and nasal cavity - warming, filtration, moistening of air 2. Oral cavity - warming, moistening of air 3. Pharynx (naso, oral, laryngo) - passageway/air conduction, filtration, prevention of food movement into trachea (epiglottis) 4. Larynx - passage way/air conduction, phonation (glottis)
The pressure difference between the intra-alveolar and intrapleural pressures is called ________.
A) atmospheric pressure
B) pulmonary pressure
C) negative pressure
D) transpulmonary pressure
D) transpulmonary pressure
Oxyhemoglobin forms by a chemical reaction between which of the following?
- A) hemoglobin and carbon dioxide
- B) carbonic anhydrase and carbon dioxide
- C) hemoglobin and oxygen
- D) carbonic anhydrase and oxygen
C) hemoglobin and oxygen
Describe the anatomy of the pleural membranes of the lung.
The lung is surrounded with 2 pleural membranes who form the pleural sac:
- Parietal pleura
- Visceral pleura
In between them is the pleural fluid/sac
Viscera: refers to organs
Parietal: the outer layer
Gas exchange that occurs at the level of the tissues is called ________.
- A) external respiration
- B) interpulmonary respiration
- C) internal respiration
- D) pulmonary ventilation
C) internal respiration
In a healthy young adult, what happens to cardiac output when heart rate increases above 160 bpm?
- A) It increases.
- B) It decreases.
- C) It remains constant.
- D) There is no way to predict.
B) It decreases.
Role of surfactant ?
Improve lung compliance.
Why does air move into the alveoli during inspiration
Slight negative alveolar pressure
In which septum is it normal to find openings in the adult?
- A) interatrial septum
- B) interventricular septum
- C) atrioventricular septum
- D) all of the above
C) atrioventricular septum
What is the alveolar wall structure?
Capillaries in the alveolar wall
Black dots = red blood cells that are carried in the capillaries = capillary networks in between alveoli
The ________ circulation picks up oxygen for cellular use and drops off carbon dioxide for removal from the body.
- A) pulmonary
- B) interlobular
- C) respiratory
- D) bronchial
C) respiratory
Which view of the bony thorax is this?
Posterior view
What is a haemothorax of the pleural space.
Why can this be a problem?
Haemothorax : fluid in the pleural space
Tends to be at the bottom of the pleural space
Impairs gas exchange because it is compressing the lung so it may make your alveoli much smaller and it may cause them to collapse
What is the function of internal intercostal muscles?
Bring ribs down during forced expiration, decreasing the thoracic capacity
Which view of the bony thorax is this?
Anterior view
What do the fibroblasts do? What is IPF?
Fibroblast = it produces new cells which are support cells that act as a fibrous structure
IPF = Idiopathic pulmonary fibrosis (IPF) causes scar tissue to grow inside your lungs. Usually, when you breathe in, oxygen moves through tiny air sacs in your lungs into your bloodstream. From there, it travels to organs in your body
What affects the central chemoreceptors, and why can’t hydrogens ions do that?
Hydrogen ion = H+ , the red block = does not pass through the cerebrospinal fluid.
It is the PaCO2 that is increased and that affects the central chemoreceptors
Where are situated the main pacemaker groups for breathing? Name both of them and what their role is.
Main pacemaker groups are in the medulla of the brain.
Two groups of cells: dorsal respiratory group, and ventral respiratory group.
Cells here have a role for inspiration, it sets the rhythm of your breathing
One is about inspiration (dorsal), but the other one is about inspiration AND expiration (ventral)
Hypocapnia
Low arterial CO2 (Low PaCO2)
Dyspnea
Difficulty breathing or the sensation of difficulty breathing
Name 2 fibrous contributors to lung elasticity
Collagen and elastin fibers
How is surface tension contributory to compliance/lung elasticity
Decreases lung compliance.
Which of the following factors play a role in the oxygen-hemoglobin saturation/dissociation curve?
- A) temperature
- B) pH
- C) BPG
- D) all of the above
D) all of the above
Which component of the heart conduction system would have the slowest rate of firing?
- A) atrioventricular node
- B) atrioventricular bundle
- C) bundle branches
- D) Purkinje fibers
D) Purkinje fibers
What are the roles of the bony thorax (rib cage)?
Role is to protect the lungs
It also protects the heart
Expansion of the rib cage allows the ventilation, change of pressures to get air into the lungs. The framework upon which the muscles work
Define compliance
the magnitude of change in lung volume as a result of change to pulmonary pressure
A decrease in volume leads to a(n) ________ pressure.
- A) decrease in
- B) equalization of
- C) increase in
- D) zero
C) increase in
What is the interstitium?
What happens when the lymphatic system doesn’t function properly?
Interstitium- a contiguous fluid-filled space existing between a structural barrier
Pink around the dark red blood cells : the interstitium, it is the fine tissue part of this very fine alveolar wall.
The lung becomes boggy when fluid isn’t taken up by the lymphatic system or because it changes the pressure in the vascular system: the fluid is being pushed out, into the lungs = makes it harder to breathe
Apnea
Suspension/cessation of breathing
What is the innervation of the diaphragm?
The Nerve supply to the diaphragm: phrenic nerve from C3, 4 and 5 = keep the diaphragm alive