Part 4 - Body Systems 1 Flashcards
(23 cards)
Each living organism has a system which:
(3 points)
- Responds to both internal and external stimuli
- Integrates the stimulus
- formulates a response
What is Sensory input?
-The function of sensory neurons
-Internal and external stimuli are picked up and transformed into an electrical impulse by a sensory receptor
-This impulse is carried to the brain and/or spinal cord for interpretation
What is Integration/Interpretation?
-This is the function of interneurons found within the brain and spinal cord.
-Interneurons receive the impulse, interpret and formulate an appropriate command
What is Motor output?
-This is the function on motor neurons
-The command is carried along motor neurons to the correct muscle, organ or gland
-Here the correct response occurs
What happens when a neuron becomes excited
They transmit electrical impulses to the brain and spinal cord
What are the two stages in the transmission of an electrical impulse along a neuron?
- Resting potential
- The action potential
A nerve impulse always travels:
(3 points)
-From the dendrites
-Through the cell body
-Then through the axons
When a neuron is in Resting state it is ____
Polarized
The Inside of the neuron’s membrane is _____ compared to the outside of the cell
Negatively charged
The difference in charge is created and maintained by the ______ _____
Sodium-Potassium pump
In depolarization:
*Sodium voltage gated channels open
*Sodium ions rush into the cell
In Repolarization:
*Potassium voltage gated channels open
*Potassium ions rush out of the cell
In Recovery period:
*sodium-potassium pump re-establishes the resting potential
*Pumps sodium ions out and potassium ions in
What are action potentials three phases?
- Depolarization
- Repolarization
- Recovery Period
Sodium-Potassium Pump
Regulates Na+ and K+ ion concentrations outside and inside axon
Threshold
Voltage required to begin action potential
Action Potential
Stimulus needed to bring axon to threshold
What are the two main divisions of the nervous system
- The Central nervous system (CNS)
*The brain and spinal cord - The peripheral nervous system (PNS)
*The nerves bringing information into and out of the CNS
What are the 3 regions of the brain
1.Hindbrain
2.Midbrain
3.Forebrain
How many classes of sensory receptors are in the human body
five (5)
Name the types of sensory receptors
-Chemoreceptors
-Thermoreceptors
-Mechanoreceptors
-Photoreceptors
-Pain receptors
What do Chemoreceptors do? and where are they found?
-Respond to chemical changes, such as pH and gases in the blood
-these receptors are also found in the nose and mouth and are responsible for our sense of taste and smell.
*found in nose mouth and blood
Where are thermoreceptors found? they are sensitive to what?
-Located in the hypothalamus and the dermal layer of the skin
-they are sensitive to changes in temperature
-there are separate receptors for cold and warm temperatures
