Exam 1 Flashcards
What is physiology?
The study of the functions of the body.
What is anatomy?
The study of the structures of body.
What is homeostasis?
Sensing internal and external changes, and responding to the changes by controlling the organ systems to maintain the composition of the internal environment.
How does negative feedback help maintain homeostasis?
When an increase in the input of a system causes a decrease in the output of the system. The new output (decreased) becomes the new input and the system is kept within the range of regulation as defined by the setpoint.
What are the components of a control system?
- Stimulus
- Sensor
- Afferent neurons
- Integrator
- Efferent neurons
- Effectors
- Response
What is the role of the stimulus?
The change in the internal or external environment that triggers the need to maintain homeostasis.
What is the role of sensor?
Acts as the receptor. Determines the presence or absence of some component in the internal or external environment, and transmit energy of stimuli to the afferent neurons.
What is the role of afferent neurons?
Deliver information from the stimulus to the integrator.
What is the role of integrator?
Receives information from the afferent neurons and analyzes to determine the appropriate output.
What is the role of efferent neurons?
Deliver information from the integrator to the effectors.
What is the role of effectors?
Receive information and elicit the response determined by the integrator.
What is the role of the response?
To return the body to a state of homeostasis.
What are the two types of effectors for the body’s control systems?
Muscles and glands.
What are the three types of muscle used by the body as effectors?
Skeletal, smooth, and cardiac.
What are the two major types of glands that can serve as effectors?
Endocrine and exocrine.
What are an example of the types of glands that can serve as effectors?
Adrenal glands (endocrine) and sweat glands (exocrine).
What is passive transport?
Energy not needed and movement down gradient.
What is active transport?
Energy needed and movement against gradient.
What is simple diffusion?
Energy not needed, movement against gradient, and carrier molecule not needed.
What is facilitated diffusion?
Energy needed, movement against gradient, and carrier molecule needed.
What are the factors involved in Fick’s law of diffusion?
Concentration gradient between Area A and Area B, temperature of diffusion molecules, solubility of substance, molecular weight of substance, area of membrane, and thickness of membrane.
How does temperature affect rate of diffusion?
Directly
How does solubility affect rate of diffusion?
Directly
How does concentration gradient affect rate of diffusion?
Directly
How does molecular weight affect rate of diffusion?
Indirectly
How does area of membrane affect rate of diffusion?
Directly
How does membrane thickness affect rate of diffusion?
Indirectly
What is agar derived from?
Seaweed
What does agar serve as a model for?
Cytoplasm
What ion moves freely across the cell membrane in the development of the resting membrane potential?
Potassium
In a single neuron, a stimulus having a voltage greater than a threshold produces an action potential with what magnitude?
The same magnitude as the threshold.
During the absolute refractory period, what type of stimulus can elicit a response from a neuron?
No stimulus can elicit a response during the absolute refractory period.
A stimulus, which elicits the smallest response from a compound nerve is what?
Threshold stimulus.
The data in lab 2 represents the electrical recording of what type of action potential?
Compound nerve.
Amplitude of action potential is represented by what?
Milivolts.
An increase in stimulus strength will result in what in the amplitude of the recorded compound action potential?
An increase.
In the body, nerve transmission is a_____due to the presence of_____
One-way process; synapses
Changes in temperature can influence the conduction velocity by…
Reducing the movement of ions across the neuron’s cell membrane.
Multiple motor unit summation occurs as a result of an increase in stimulus_____
Strength
Wave summation occurs as a result of increase in stimulus_____.
Frequency
Following muscle tetany, it should take_____ time for the muscle to recover due to the depletion of _____.
More; ATP.
What are skeletal muscles innervated by?
Somatic motor neurons.
In skeletal muscles, the release of calcium from the_____ initiates the contractile process in the sarcomere.
Sacroplasmic reticulum.
In skeletal muscle, ATP initially binds with…
Myosin
What is a motor unit?
A single neuron and the muscle fiber it innervates.
What is the result of increasing the frequency of stimulation?
Wave summation.
What agents will increase smooth muscle contractions?
Acetylcholine and pilocarpine.
What is plasticity?
The ability of smooth muscle to reform actin-myosin cross-bridges after being stretched and reduce the amount of tension the muscle is under.
What input is no longer present when isolated tissue is prepared?
Autonomic nervous system and enteric nervous system.
What is one of the pharmacological agents in an adrenergic agent?
Epinephrine
What is an antagonist?
A substance that binds to receptor and blocks the effect of neurotransmitters, hormones, or drugs.