Exam 2 Flashcards
What are the main cells of the nervous system?
Neurons
What are the electrical signals generated by nervous system called?
Action Potential
How does the central nervous system differ from the peripheral nervous system?
Central - includes brain and spinal cord
Peripheral - any nerve cell outside brain and spinal cord
How does the Somatic division differ from the Autonomic division?
Somatic - under conscious control
Autonomic - under unconscious control
How does the Sympathetic Branchof the autonomic division differ from the Parasympathetic Branch?
Sympathetic - stimulates fight or flight
Parasympathetic - relaxes body
State 1 example of a Sympathetic Branch response on an organ.
Increase heart rate
State 1 example of a Parasympathetic Branch response on an organ.
Decrease heart rate
What is the name of the gap that sits between 2 neuurons?
Synaptic cleft (Synapse)
What is the name of the gap that sits between a neuron and a muscle cell?
Neuromuscular junction
What is the name of a neuron that SENDS neurotransmitters to another?
Presynaptic
What is the name of a neuron that RECEIVES neurotransmitters from another?
Postsynaptic
Explain in detail the 8 steps involved in generating an action potential.
- During resting state, cell has a net negative charge
- Stimulus will open sodium channels, allowing sodium to enter cell
- The entry of sodium causes the cell to become more positive (depolarization)
- Sodium channels will close and potassium channels will open.
- Potassium atoms will leave cell
- The cell becomes more negative as potassium leaves (repolarization)
- Potassium channels are slow to close, cell becomes more negative (hyper polarization)
- The sodium - potassium pump fixes the membrane gradient to return to resting state
What type of activities does the cerebral cortex do?
higher-level thinking functions
How does the cerebral cortex left hemisphere differ from the right hemisphere?
Left
- logical
- math-based
Right
- emotional
- artistic based
Which lobe of the brain is responsible for controlling vision?
occipital lobe
What does the medulla oblongata control?
Breathing, heartbeat, blood pressure
Write 1 function of the cerebellum.
controls eye movement
What does the Amygdala regulate?
emotions
What does the Hippocampus regulate?
Learning, memory
What does the Thalamus do?
Relay station for motor signals and senses
Explain how vision happens.
- Light passes through cornea
- Light passes through pupil
- Iris regulates diameter of pupil
- Lens focuses incoming light to retina
- Retina converts light to electrical signals
- Optic nerve transports electrical signals to brain
Explain how hearing happens.
- The auricle collects sound waves
- The external auditory canal transports them deeper into ear
- Tympanic membrane vibrates and amplifies the sound waves
- Sound waves are relayed between the malleus, incus, and stapes to inner ear
- Round window receives the sound waves and passes them to cochlea
- Cochlea transforms sound waves into electrical signals
- Cochlear nerve transmits electrical signals to brain
What is the name of the cell membrane found in a muscle fiber?
Sarcolemma
Name the organelle that stores calcium inside a muscle fiber.
SR
What name is used to describe a long contractile thread found in muscle fibers?
myofibril
Explain what a sarcomere is and state the function it carries out
The contractile unit of a muscle fiber
Name the 2 protein filaments involved in the muscle contraction process
Myocin
Actin
Name the type of muscle that attaches to bones.
Skeletal
How does skeletal muscle differ from smooth muscle?
Skeletal - somatic control
Smooth - autonomic control
Fully explain the muscle contraction mechanism in 10 steps.
- Action potential is generated by a presynapic neuron which triggers the release of NT
- NTs will bind to receptors on the SL
- This binding triggers the release of calcium from the SR
- Calcium binds to troponin
- This causes tropomyocin to shift off binding sites of actin
- Myocin heads bind to actin to form a cross bridge
- Myocin heads pull actin filament forward, causing sarcomere to shorten
- The cross bridge is broken by binding of ATP
- Actin moves back to original position, causing muscle to relax
- Calcium atoms will move back to SR