Lab 13 Flashcards
Is located in the medulla oblongata where it receives input from various sensory receptors (proprioceptors, baroreceptors, chemoreceptors) and higher brain centers (cerebral cortex, limbic system).
Cardiovascular center
Output from the cardiovascular center is via ________ and __________ neurons of the autonomic nervous system.
Sympathetic; parasympathetic
Cardiac excitation normally begins at the __________ node (dominant pacemaker of the heart) which lies in a cellular cluster in the right atrial wall between the inlets of the inferior and superior vena cava
Sinoatrial (SA)
Located within the lower interatrial septum, relays the impulse from the atria to the ventricles.
Atrioventricular (AV) node
After the impulse passes through the AV node, it enters the fiber tract known as the AV bundle or
Bundle of His
This short pathway subdivides into ______ and _____ bundle branches. The bundle branches extend through the interventricular septum toward the apex of the heart
Right; left
The smallest conductive elements, the _______ _______, are distributed throughout the inner walls of the ventricles, throughout the muscular septum separating the two ventricles, and within the muscular papillae where they make intimate contact with contractile elements of the heart.
Purkinje fibers
The measurement and analysis of currents associated with heart activity, is extremely important in the diagnosis of abnormal cardiac function.
Electrocardiography
The recording of the electrical changes
Of the heart is called an:
Electrocardiogram (ECG or EKG).
The heart is seen as a dipole, i.e. a pair of point sources of electrical charge equal in magnitude but opposite in sign. Current flows between the two poles throughout the volume conductor. The particular arrangement of the two electrodes is known as a:
Lead
The normal electrocardiogram is composed of a:
P wave, a QRS complex and a T wave
The upward (positive) deflection associated with atrial depolarization. The average duration is 0.08 second (range 0.06 - 0. 12 sec) and the amplitude (height) is not greater than 0.3 millivolts.
P wave
Series of negative and positive deflections associated with ventricular depolarization, It is measured as the portion of the tracing from the beginning of the Q wave to the end of repolarization of the atria takes place simultaneously and is obscured by the ventricular
changes. The average duration is 0.08 second (range 0.06 - 0.10 sec) and the amplitude of the R wave is not over 2.5 millivolts.
QRS complex
The positive deflection following the QRS complex representing ventricular repolarization.
T wave
The T wave is of longer duration and lower amplitude than the initial depolarization (QRS complex), which suggests that the ventricular repolarization is ______ and less well synchronized.
Slower
An _______ (negative) T wave is considered to be abnormal.
Inverted
The average duration of the T wave is about 0.16 second; the amplitude is about 0.3 millivolts but is:
Highly variable
a-b atrial _________
Contraction
b-c atrial _________
Relaxation
c-d ventricular _________
Contraction
d-e ventricular _________
Relaxation
The term ______ refers to the alternating surges of pressure (expansion and then recoil) in an artery
that occur with each contraction and relaxation of the left ventricle.
Pulse
Normally the pulse rate (pressure surges per minute) equals the heart rate (beats per minute) and the pulse averages _______ beats per min
70 - 76
This pressure varies with the cardiac cycle, whether the heart muscle is in _______ (contracted state) or in _______ (relaxed state).
Systole; diastole
You will use an instrument called a sphygmomanometer to measure _______ blood pressure.
Arterial
Systolic pressure can be defined as the
maximum pressure in the arteries during ventricular __________ (systole).
Contraction
Diastolic pressure is the minimum pressure in the arteries during ventricular _________ (diastole).
Relaxation
The Valsalva maneuver which increases intrathoracic pressure, can be used to demonstrate the effect of thoracic pressure changes on:
Venous blood pressure
Veins have _______ to prevent blood flowing backward in them.
Valves
Air enters the nasal cavity through external openings known as the:
Nostrils or external nares
The lateral walls of this cavity have three bony projections:
Superior, middle and inferior nasal conchae.
The conchae divide the nasal cavity into _ passageways.
3
Between the nasal cavity and the mouth, lies a partition, the ________.
Palate
The anterior portion of the palate is rigid due to bone reinforcement and is called the ______ ______
Hard palate
The posterior part of the palate lacks bone and is referred to as the ______ ______
Soft palate
From the nasal cavity, air passes successively through the three regions of the pharynx:
The nasopharynx, the oropharynx and the laryngopharynx
The ____________ is a region just above and behind the soft palate.
Nasopharynx
The ___________ is the region posterior to the mouth
Oropharynx
The ___________ is the region posterior to the larynx.
Laryngopharynx
The _________ is an elongated flap that extends diagonally over the entrance to the larynx.
Epiglottis
The epiglottis is the only laryngeal cartilage composed of:
Elastic cartilage
From the larynx, air enters the ________
Trachea
The trachea divides into two smaller branches:
Primary bronchi (L&R)
Each primary bronchus divides several times into still smaller secondary _______, one for each lobe of the lung.
Bronchi
The secondary bronchi divide into still smaller branches called the tertiary bronchi that divide into __________.
Bronchioles
The bronchioles, in turn, branch repeatedly divide becoming terminal brochioles dividing into still smaller:
Respiratory bronchioles
Respiratory bronchioles subdivide into _________ _______ that terminate in the alveolar sacs, where gas exchange occurs between the air and the blood in individual alveoli.
Alveolar ducts
Free movement of the lungs in the thoracic cavity is facilitated by the:
Pleural membranes
Between these two pleurae is a potential space, the pleural cavity, which contains just enough pleural fluid for __________.
Lubrication
When the lungs are inflated with air, the moist visceral pleura adheres to the moist:
Parietal pleura
Is the movement of air into and out of the respiratory tract
Breathing, or pulmonary ventilation
There are two different respiratory movements involved in breathing:
Inspiration
Expiration
The movement of air into the respiratory system
Inspiration or inhalation
The movement of air out of the respiratory system.
Expiration or exhalation
The volume of air inspired or expired with each normal, quiet respiration
Tidal Volume (TV)
The volume of air that can be forcibly expired after a normal expiration.
Expiratory Reserve Volume (ERV)
The maximum amount of air that can be moved into and out of the lungs from a maximal inspiration to a maximal expiration.
Vital Capacity (VC)
The rate and depth of respiration can be altered in response to input from other brain regions, input from receptors in the lungs, muscles and joints and input from central and peripheral ______________.
Chemoreceptors
Central chemoreceptors, located in the ______ respond to increases in pCO2 and hydrogen ion concentration of the cerebrospinal fluid.
Medulla
Peripheral chemoreceptors, located in the ________ and carotid arteries, respond to increases in pCO2 and H* and to decreases in pO2, of arterial blood.
Aortic arch
To produce a tracing of __________, a subject would inspire normally (upward trace) and make a normal expiration (downward trace) into the mouthpiece. This process would be repeated 3 to 4 times and an average calculated
Tidal Volume (TV)
To produce a tracing of _________________, a subject would inspire normally and make a maximal expiration.
This process would be repeated at least 2 more times.
An average would be calculated and the value obtained for tidal volume would be subtracted.
Expiratory Reserve Volume (ERV)
To produce a tracing of ___________, the subject would inspire maximally and make a maximal expiration. This process would be repeated at least two times and an average calculated
Vital Capacity (VC)
Will not result in an increase in arterial blood pressure:
Reclining for several minutes
It is not possible to measure venous pressure with a sphygmomanomter because blood pressure is too:
Low
