Nervous System Study Guide Flashcards
What are the two primary divisions of the nervous system?
The Central Nervous System (CNS) and the Peripheral Nervous System (PNS)
What primary areas do the two main divisions of the nervous system cover?
The CNS is the brain and spinal cord, the PNS is all other neural tissue
What are the further divisions of the PNS?
The PNS is divided into the Afferent and Efferent groups. The Efferent group is divided into the Somatic and Autonomic systems. The Autonomic system is divided into the Sympathetic and Parasympathetic systems.
What two categories is the PNS divided into?
The Afferent (sensory) and Efferent (effector) groups
What is the efferent division of the PNS divided into?
The somatic (voluntary) and autonomic (involuntary) divisions
What is the autonomic division of the PNS divided into?
It’s divided into the sympathetic (stimulating) and parasympathetic (calming) systems
What are the basic functions of the CNS?
To processes and coordinate
What are the functions of the CNS in-depth?
To process and coordinate: sensory data from inside and outside the body, motor commands that control activities of peripheral organs, and higher functions of the brain (like intelligence, memory, learning, and emotion)
What are the functions of the PNS?
To deliver sensory info to the CNS, and carry motor commands to the peripheral tissue systems
What does the afferent division of the PNS do?
It carries sensory info from the PNS sensory receptors to the CNS receptors
What does the efferent division of the PNS do?
It carries motor commands from the CNS, to the PNS, and then to the effectors (muscles and glands)
What is the function of the somatic nervous system (SNS)?
It controls skeletal muscle/ voluntary muscle contractions
What is the function of the automatic nervous system (ANS)?
It controls subconscious contractions/ contractions of smooth and cardiac muscle
What does the sympathetic division of the ANS do?
It has a stimulating effect
What does the parasympathetic division of the ANS do?
It has a relaxing effect
What are the two different cell types in the nervous system and their general functions?
Neurons and neuroglia. Neurons send and receive signals, and neuroglia support and protect the neurons.
What are the major organelles of a neuron cell (or lack thereof)
They have a nucleus, nucleolus, cytoplasm, mitochondria, RER, ribosomes (nissl bodies), cytoskeleton. No centrioles.
What is the size of the axon? What is its function?
It’s long and carries electrical signals (action potentials) to the target
Describe the axon hillock
It’s a thick section of the cell body and it attaches to the initial segment
What are the collaterals?
The branches of a single axon
What are the axon terminals?
Also called the synaptic terminals, they’re the tips of the axon