Nervous System Flashcards
CNS is compromised of:
Brain and spinal cord
PNS is compromised of:
All other neurons/nerves in the body
Sensory (afferent) neurons:
Transmit nerve impulses toward the CNS
Motor (efferent) neurons:
Transmit nerve impulses away from the CNS toward the effector organs (muscles, glands, digestive organs)
Major parts of the brain:
Cerebrum
Cerebellum
Medulla oblongata
Cerebrum:
Associated with movement and sensory input
-Voluntary activities
Cerebellum:
Responsible for muscular coordination and balance
-Motor skills
Medulla oblongata:
Controls respiration, heart rate, swallowing
Simple spinal reflexes:
Nerve impulses travel through the spinal cord only and do not reach the brain
How many nerves exit the spinal cord?
31
Spinal cord extends from:
Base of the skull (foramen magnum) to the first or second lumbar vertebra
Sensory impulse reflex pathway:
Enter the dorsal horns of the spinal cord
Motor impulse reflex pathway:
Leave through the ventral horns of the spinal cord
Main parts of a neuron:
Cell body, axon, dendrites
Dendrites:
Transmit impulses toward the cell body through synapses
Axon:
Transmits impulses away from the cell body to other neurons
Neurons:
Transmit action potentials
Neuroglia:
Connective tissue cells that connect and supports neurons
Hypothalamus:
Controls hormones, memory, emotions
2 divisions of the PNS:
Autonomic and somatic nervous system
Autonomic nervous system:
Nerves?
Governs involuntary and reflexive body functions (CNS to cardiac muscles, smooth muscles, glands)
- Sympathetic nerves: fight or flight
- Parasympathetic nerves: rest and digest
Somatic nervous system:
Neurons?
Governs conscious or voluntary control of skeletal muscles
- Sensory (afferent)
- Motor (efferent)
Shwann cells:
Produce myelin sheaths
Myelin sheaths:
A layer of fatty tissue that encases the neuron fibers, which allows for greater transmission speed of neural impulses
CNS has a protective covering known as the meninges. Which layer is the thickest and toughest layer?
Dura mater
Then arachnoid mater (middle), followed by pia mater (innermost)
Where does the carotid artery take blood?
Brain
How do nerve cells communicate?
Via neural signaling
Which chemicals convey an impulse along a nerve cell?
Sodium and potassium
What does the amygdala do?
Responds to fear, emotion, memory
Hippocampus:
Converts temporary memories into permanent ones
Thalamus controls:
Pain sensation and attention span
Wernicke’s area function:
Comprehension of speech
Spinal cord’s gray matter:
Unmyelinated interneurons
Spinal cord’s white matter:
Myelinated neurons
