Unit 2: Respiratory System and Nervous System Flashcards
What are the 3 main functions of the respiratory system
supply oxygen to blood
remove carbon dioxide from blood
regulate blood pH
what is respiration
movement of gases throughout body
what is external respiration
processes that occur within lungs
What is internal respiration
exchange of gases at tissue level i.e. between blood and muscle tissue
what is celluar respiration
process where cells use oxygen to generate energy through metabolic pathways
what is ventilation
combination of inspiration and expiration
volume of air that is moved by lungs in 1 minute
What is tidal volume
volume of air in each breath
what is respiratory frequency
number of breaths taken per minute
What are the 3 static lung volumes and what are they determined by
Total lung capacity, Vital capacity, Residual volume, determined by actual structure of lung (not by breathing or flow of air)
what is vital capacity
max amount of air that can be exhaled following max inhalation
What is total lung capacity
maximum volume of air lungs can hold
What is residual volume
air that remains in lungs following max exhalation
what is diffusion
movement of gas, liquid or solid from region of high concentration to region of low concentration
What is oxygen transport and how does it happen
oxygen binds to specialized protein (hemoglobin) found in erythrocytes (red blood cells) due to coopertivity.
only 2% of oxygen found in blood is dissolved in plasma (fluid component of blood), rest bound to hemoglobin
What is blood pH
measure of how acidic or basic blood is
does exercise make blood more acidic or basic
during exercise, where large amounts of acid released into blood (lactic acid), pH declines (becomes acidic)
How does ventilation play an important role in maintaining blood pH
by expelling extra amounts of CO2, causing more H+ to combine with bicarbonate to eventually form CO2 and H2O, therefore lowering H+ ions and increasing pH back to normal levels
What is VO2 Max
Maximal Rate of Oxygen Consumption (VO2max). Theoretically, VO 2 is a function of both O2 delivery to and O2 uptake by the working muscle and other tissues.
When would VO2 Max take place
Therefore, the maximal rate of oxygen consumption (VO2max) would theoretically occur at maximum SV, HR, and a-vO2 diff.
The combination of inspiration and expiration is known as
ventilation
the primary factor that mediates gas exchange both at the lung and tissue level
diffusion
the exhange of gasses at the level of the lungs
external respiration
as the diaphargm contracts, the thorasic cavity
pulls downward and enlarges
What are the two types of stretch reflexes
Monosynaptic and Polysynaptic
What is a monosynaptic stretch reflex
Simplest spinal reflex
Only relies on the single connection between primary afferent fibres and motor neurons of the same muscle.
Extremely quick and automatic
What is a polysynaptic stretch reflex
one or more interneurons lie between the primary sensory fibers and the motor neurons.
What is an example of a monosynaptic reflex and how does it work
The knee-jerk is often used to demonstrate this type of reflex.
A tap below the kneecap stretches the patellar tendon and acts as a stimulus, initiating a reflex arc that causes the exterior muscle on top of the thigh to contract.
As the tendon and muscle fibre are stretched, information is sent to the spinal cord. These nerve signals act directly on motor neurons that then quickly proceed to contract the quadriceps femoris, the extensor muscle that serves to extend the lower leg
Sequence of nerve impulses:
The receptor muscle senses the action of the hammer against the patella ligament through the muscle spindle’s sensory neuron;
The message is transmitted along the afferent (sensory) nerve axon to the spinal cord;
The afferent neuron then synapses with the efferent pathway (motor neuron) of the same muscle;
An impulse is transmitted along the efferent pathway (motor neuron) to the muscle fibre; and
The motor units contract simultaneously, which in turn brings about a knee-jerk action to accommodate the additional stretch.
What is an example of a polysynaptic reflex and how does it work
An example is the withdrawal reflex, which involves the withdrawal of a body part from a painful stimulus (such as a sharp or hot object).
the reflex action involves transferring the impulse from a sensory neuron to a motor neuron through a connecting interneuron in the spinal cord. The withdrawal reflex process occurs before the brain itself has time to interpret the information.
The sequence of nerve impulses and stages activated in the crossed leg extensor reflex action are as follows:
The stimulus is detected by receptors (say, on the skin)
The receptors initiate nerve impulses in the sensory neurons leading from the receptors;
The impulses travel into the spinal cord where the sensory nerve terminals synapse with interneurons;
Some of these interneurons synapse with motor neurons that travel out from the spinal cord to the effector organ;
The knee flexors withdraw the foot from the danger zone; and
Still other sensory neurons synapse with interneurons that affect motor neurons in the opposing leg and cause these muscles to come into action.
What are the two types of nervous systems
Central nervous system and Peripheral nervous system
What is the CNS and what does it do
Consists of brain and spinal cord
Processes information sent by PNS and acts as a command center
Can execute motor responses or regulate body mechanisms
What is the PNS and what does it do
Provides sensory information for the CNS
Further divided into SNS and ANS
What two categories is the PNS split into
Automatic nervous system and somatic nervous system
What is the function of the ANS
deal with the internal environment: Can be divided into Sympathetic and Parasympathetic
What is the function of the Parasympathetic nervous system
Rest and Digest
Heart rate will decrease
What is the function of the Sympathetic nervous system
Part of the quick flight or fight response
Increased heart rate
Increased breathing rate
