Chapter 11 & 12 Flashcards
Describe the function of the meninges
The function of the meninges is to cover and protect cns, protect blood vessels and enclose venous sinuses. Contain cerebrospinal fluid, form partitions in skull.
Cerebral cortex
Maintains our conscious state, helps us decide how to react to situations
Broca’s area
Involved in speech formation
Thalamus
Gateway to the cerebral cortex, mediates sensation and motor activities
Pons
Connects brain centers and helps maintain the normal rhythm of breathing
Sensory (afferent) division
Conducts impulses from receptors to the CNS
Motor (efferent) division
Conducts impulses from the CNS to effectors (muscles and glands)
Somatic nervous system
Conducts impulses from the CNS to skeletal muscles
Autonomic nervous system
Conducts impulses from the CNS to cardiac muscle, smooth muscle, and glands
Sympathetic division
Mobilizes body systems during activity
Parasympathetic division
Conserves energy promotes house keeping functions during rest
Neurons
Located in the brain, they are highly excitable cells that are capable of conducting electrochemical impulses that enable the nervous systems function
Describe the limbic system and reticular formation based on functionality
The limbic system interacts with prefrontal lobes, allows us to react emotionally to things we consciously understand to be happening. Reticular activating system sends impulses to cerebral cortex to keep it conscious and alert
Describe the makeup of CSF
Composed of watery solution formed from blood plasma, but with less protein and different ion concentrations from plasma
Sensory neurons
Detect stimuli, such as heat, light, and pressure. Sends the stimulus to the CNS
What is an action potential and how does it occur
An action potential is a change in electrical potential in muscle or nerve cells. It is an increase or decrease in membrane potential of a concentration gradient. It occurs when sodium channels open and ions cross the membrane, making the resulting gradient either more or less permeable
What is a resting membrane potential and how is it established
Resting membrane potential is the voltage that exists during the resting state of an excitable cell. It is established when the sodium-potassium ion pump transports two potassium ions inside of the cell and sends three sodium ions outside of the cell
What occurs at the synapse
The synapse is the site where neurons are separated via the synaptic cleft. It is where the neurons react to different stimuli
Distinguish between excitatory and inhibitory postsynaptic potentials
Excitatory - voltage change approaches the threshold making an AP more likely to be depolarized
Inhibitory - voltage change goes away from the threshold, making an AP less likely to be hyperpolarized
What are neurotransmitters and how do they function (be able to give some examples)
Neurotransmitters are chemical impulses that causes a transfer of impulses to another nerve fiber. They function in response to a stimulus given off by neurons ex: acetylcholine, dopamine, endorphins
Interneurons
Lie within the CNS between motor and sensory neurons, and receives signals from sensory neurons, interprets the signals, then stimulates outgoing motor neurons
Motor neurons
Sends signals to muscle and gland cells
Step 1 of action potential
Resting state: all gated na+ and k+ channels are closed
Step 2
Depolarization: na+ channels are open, allowing their entry
Step 3
Repolarization: na+ channels are inactivating. K+ channels open allowing it to exit
Step 4
Hyperpolarization: some k+ channels remain open and na+ channels reset
