New nervous system Flashcards
What are the two main divisions of the nervous system?
Central Nervous System (CNS) and Peripheral Nervous System (PNS).
What structures make up the CNS?
The brain and spinal cord.
What structures make up the PNS?
Nerves and ganglia outside the CNS.
What are the two subdivisions of the PNS?
Somatic Nervous System and Autonomic Nervous System
What are the two divisions of the Autonomic Nervous System (ANS)?
Sympathetic division (fight or flight) and Parasympathetic division (rest and digest).
What is the function of sensory (afferent) neurons in the PNS?
They carry electrical impulses from receptors to the CNS.
What is the function of motor (efferent) neurons in the PNS?
They carry electrical impulses from the CNS to muscles and glands.
What is the function of the somatic nervous system?
Controls voluntary movement
What is the function of the automatic nervous system?
Regulates functions of internal organs through involuntary movement
What is the difference between gray matter and white matter?
Gray matter: Contains neuron cell bodies.
White matter: Contains myelinated axons (nerve fibers).
Explain structure of the Tract
Bundle of axons within CNS
What are the three components of a neuron?
Cell body, dendrites, axon.
What is the function of dendrites?
They receive signals from other neurons and conduct impulses toward the cell body.
What is the function of an axon?
It conducts impulses away from the cell body toward other neurons or muscles.
What are myelinated neurons?
Neurons covered in a myelin sheath that insulates and speeds up signal transmission.
Explain the ganglion
A collection of cell bodies of neurons outside the CNS.
Explain the structure of a nerve.
Bundle of axons within the PNS
What is the function of neuroglia?
Support, segregate and insulate neurons, protection
What is a reflex arc?
A fast, automatic response to a stimulus that bypasses the brain.
What are the components of a reflex arc?
Receptor, sensory neuron, integration center, motor neuron, and effector.
What is the role of the cerebral cortex
interpretation of sensory stimuli, thoughts and emotion
What are the three main parts of the brainstem?
Midbrain, Pons, and Medulla Oblongata.
What is the function of the medulla oblongata?
Regulates cardiovascular and respiratory centres (involuntary movement)
What is the main function of the cerebellum?
Maintains motor movements
What is the function of the hypothalamus?
It regulates autonomic functions, body temperature, hunger, thirst, endocrine system, homeostasis
What is the function of the thalamus?
Sensory relay center
What is the diencephalon?
It is the central core of the forebrain, containing the thalamus and hypothalamus.
What is the Midbrain?
Between diencephalon and the pons, reflex centre for head and eye movements.
What is the pons?
between midbrain and medulla oblongata, sensory and motor fibres pass through, regulates respiration
What are the main functions of the spinal cord?
It conducts sensory and motor impulses
What is the “cauda equina”?
A bundle of nerve roots extending from the lower end of the spinal cord.
What is the structure of the spinal cord?
gray matter (inner part) and white matter (outer part), with spinal nerves branching from it.
What is a reflex arc?
A fast, automatic response to a stimulus that bypasses the brain.
What are the five components of a reflex arc?
- Receptor
- neuron
- Integration center (spinal cord)
- Motor neuron
- Effector (muscle or gland
What are some functions of the sympathetic nervous system?
ncreases heart rate, dilates pupils, slows digestion, and increases blood flow to muscles.
What are some functions of the parasympathetic nervous system?
Decreases heart rate, constricts pupils, stimulates digestion, and promotes relaxation.
Explain action potential
When a neuron sends information down an axon away from the cell body.
What key factors affect the resting membrane potential?
- Na/K pump
- Presence of leaky K channels
- Large quantities of negatively-charged protein molecules
