Flashcards in Cardiac, Neuro, and Respiration for physiology Deck (115):
What is the normal heart rhythm and what is it controlled by?
sinus rhythm and by the SA node
when the heart rate is too fast or too slow
What is the contractility of the myocardium determined by?
calcium ions with actin and myosin
What greatly impacts the contractilty of the myocardium?
the sympathetic NS
What is heart rate determined by?
the automatic system and the SA node
How is heart rate determined?
from the balance between the sympathetic and the parasympathetic ns
Which makes the heart rate faster?
Which makes the heart rate slower?
What's an electrocardiogram?
graphic recording of electrical activity of the heart showing the directions impulses are traveling
In an ECG what does the P, QRS, and T mean?
atrial depolarization, ventricular depolarization, ventricular repolarization
What is heart rate?
frequency of cardiac cycle bpm
Do smaller or larger animals have higher rates and why?
smaller due to large surface area per unit of body mass
What is a cardiac auscultation?
listening to the heart
What does Lub do?
closes the AV valves
What does Dub do?
closes the semilunar valves
What is cardiac muscle fiber made up of?
striated, involuntary, branched with a single central nuclei and intercalculated discs
How do impulses travel in cardiac muscle fiber?
from cell to cell in intercalculated discs
Where is the SA node and what originates there?
the right atrium and impulses originate there
What is peripheral resistance?
blood flow that is limited by friction
How can blood flow through peripheral resistance?
blood pressure must be greater
The difference between the systolic and diastolic pressures is?
What is blood pressure?
the force exerted by the blood against inner walls of blood vessels
Maintenance of normal blood pressure prevents what?
What is the maximum pressure achieved during ventricular contraction?
systolic blood pressure
What are the functions of the cardiovascular system?
maintenance of normal blood pressure with the arteries, maintenance of blood flow to the tissues, maintenance of normal blood pressure within the capillaries and veins
What is the mode of travel of an impulse along a myelinated nerve?
Do impulses travel faster in myelinated fibers or nonmyelinated fibers?
In myelinated axons depolarization can only occur at?
nodes of ranvier
What are meninges?
connective tissue surrounding the brain and spinal cord
What is cerebrospinal fluid?
fluid between meninges and the brain and the spinal cord that cushions it
What is the blood brain barrier?
barrier separating the capillaries in the brain from the nervous tissue and acts as a protectant
What's the resting membrane potential?
electrical difference in charges across the cell membrane
When a cell is positive on the outside and negative on the inside this means?
A change in charge during depolarization?
During depolarization and repolarization neurons cannot respond to new stimuli this is called what?
In the sympathetic NS what is released?
In the parasympathetic NS do GI, intestinal, and muscle secretions increase or decrease?
Impulses that go toward the CNS and are sensory
Impulses away from CNS and are motor
What provides structural and functional support and protection for the NS?
What is a sensory receptor that receives impulses?
What conducts impulses away?
What volume of air is inspired and expired during 1 breath?
What volume is inspired and expired during 1 minute?
What volume is air left in the lungs after maximum expiration?
Inhalation that uses the diaphragm and external intercoastal muscles?
Exhalation that uses the internalcoastal muscles and abdominal muscles
What is respiration?
the exchange of oxygen and carbon dioxide
The internal respiration is
blood cells of the body
The external respiration is
air and blood in the lungs
The primary functions of respiration are
internal and external respiration
The secondary functions of respiration
phonation, body temperature, acid-base, and olfaction
What does respiration require?
effective air movement into and out of the lungs and appropriate rate and volume for O2 at any time
What is negative intrathoracic pressure?
pressure within the thoracic is negative with respect to the atmospheric pressure
How does negative inthrathoracic pressure work?
this partial vacuum pulls the lungs tightly against the thoracic wall
What is a lubricant for intrathoracic pressure?
In pulmonary circulation what divides the lungs into right and left arteries?
From the right and left arteries what do the blood vessels do?
they subdivide to coinicide with the bronchial tree
At the capillary level there is a network of capillaries around the alveoli where what takes place?
the exchange of oxygen and carbon dioxide take place
Oxygenated blood enters what which lead to larger veins? which leads to which atrium?
pulmonary venules and the left atrium
pulmonary veins carry oxygenated blood to the left atrium through?
left av vale (mitral)
After going through the mitral valve where does the blood go? which respiration is this for?
out through the aorta and through systemic circulation for internal respiration
Something going from areas of high concentration to low concentration is?
Air in the alveoli of the lungs are only 2 thin epithelial layers away from what?
from blood in the capillaries around the aveolar sacs
Because oxygen levels in the alveoli are high...
oxygen simply diffuses across the alveolar and capillary walls into the blood where the oxygen concentration is low (opposite can happen)
Breathing is controlled by what? where is it located?
the respiratory center and it's the area in the medulla obolongata of the brainstem
Is breathing voluntary or involuntary?
What are the two systems of breathing?
mechanical and chemical
Mechanical breathing is?
stretch receptors in the lung, it maintains normal, rhythmic and resting breathing patterns
Chemical breathing is?
receptors in the carotid arteries, aorta (carotid and aortic bodies) and in the brainstem
With any imbalance of respiration what happens?
chemical control system signals respiratory center to adjust breathing
Increases of CO2 are linked with decreases in?
A slight lowering of the O2 in the blood can result in?
If O2 levels drop too low what happens?
the rc neurons become depressed and can't send impulses which can lead to stopped or decreased breathing
2 connective tissue bands that stretch across the lumen of the larynx that vibrate as air passes over them producing sound
What is body temperature?
blood vessels under epithelium in nasal cavity warm inhaled air
Explain how panting works
panting cools blood via increased evaporation of fluid from nasal passages and mouth
What is acid-base balance?
it alters CO2 and pH of blood
What are the functions of the nervous system?
sensory, integration, and motor
How is the nervous system organized?
anatomical location, direction of impulses, and function
What are sympathetic decreases?
What is an example of an excitatory transmitter?
dopamine, epinephrine, norepinephrine
What are the parasympathetic increases?
intestinal muscle and secretions
What is an example of inhibitory transmitters?
glycine and GABA
A stimulus strong enough to cause threshold to be reached increases the what?
permeability of a neuron cell membrane to sodium ions
Sodium channels open and influx of sodium causes adjacent sodium channels to open is
wave of depolarization
The conduction of the action potential is
a nerve impulse
When threshold is reached the action potential is conducted along the entire neuron and depolarizes with maximum strength or it doesn't at all
Nerve impulses are transmitted from neurons to target tissues or to other neurons via
A neurotransmitter is?
the chemical released during synaptic transmission
The receptor of the neurotransmitter is the
The neurotransmitter binds with a specific protein..
receptors on postsynaptic membrane triggering a change in the postsynaptic cell
What make up the brain?
cerebrum, cerebellum, diencephalon, brainstem
What part of the brain is responsible for conscious thought and interpretation of sensory information?
What does the cerebellum control?
movement and balance
What is the diencephalon?
the passageway between the brain stem and the cerebrum
The thalamus, hypothalamus, and pituitary gland are components of?
The brainstem is what?
the connection between the brain and spinal cord
The medulla, the pons, and the midbrain are components of
Describe how a reflex arc works
Stimulation of sensory receptor>motor neuron in the CNS send an impulse to target organ>response
What are used to aid in the diagnosis of spinal cord trauma, peripheral nerve damage or muscle disease?
stretch(patellar) reflex, withdrawl(flexor) reflex, cross(extensor) reflex
Which circulatory system is a high pressure system?
systemic arterial circulation
What is required to perfuse tissues with a high resistance to blood flow? what is an example of a tissue?
hydrostatic pressure, heart, kidney
What does the pulmonary arterial/venous and systemic venous circulation have in common?
low pressure, low resistance to blood flow, high pressure can cause fluid to leak which accumulates to form edema
When is the heart relaxed, filling with blood, and blood pressure falling?
When is the heart having atrial/ventricular contractions, ejecting blood into systemic/pulmonary circulations, and blood pressure rising?
During systole/diastole blood in the right/left ventricle is pumped into the lungs through the semilunar valve called the aortic/pulmonic valve.
systole, right, pulmonic
When ventricles contract and blood is ejected into large arteries..
arterial walls stretch/recoil as pressure increases and decreases>felt as a pulse
In the sympathetic NS during peripheral resistance what happens?
vasoconstriction of arterioles>increase in blood pressure and resistance
At rest which system is dominant and blood goes where?
parasympathetic is dominant>blood flow is directed towards digestive and other organs
Why are electrical impulses conducted across specific pathways?
so specific parts of the heart activated at the right time
Sequence of electrical impulses (step 1)
SA node depolarizes>wave of depolarization>Atrioventricular node(AV)
Sequence of electrical impulses (step 2)
impulses travel slowly so atrias fill up before impulse conduction across the atrial myocardium>stimulates atrial contraction/empties blood into ventricles
Sequence of electrical impulses (step 3)
impulses go through AV node to the bundle of the interventricular(IV) septum>travel in right and left bundle branches to ventricular apex/purkinje fibers>ventricular contraction