The Nervous System and Senses Flashcards

Flashcards about the nervous system including cells, divisions, actions potentials, and senses

What are the two kinds of cells in nervous tissue?

Neurons and Neuroglia

What is the function of neurons?

Intercellular communication

What is the function of neuroglia?

Essential to survival and function of neurons; preserve structure of nervous tissue.

What are the divisions of the nervous system?

Central Nervous System (CNS), Peripheral Nervous System (PNS), and Enteric Nervous System (ENS)

What does the CNS consist of?

Brain and spinal cord

What are the divisions of the PNS?

Afferent and Efferent

What is the function of the afferent division of the PNS?

Carries sensory information

What is the function of the efferent division of the PNS?

Controls skeletal muscle contractions, subconscious actions, contractions of smooth and cardiac muscle, and glandular secretions.

What are the divisions of the efferent division?

Somatic and Autonomic

What are the divisions of the Autonomic Nervous System?

Sympathetic and Parasympathetic

What is the function of the sympathetic division of the ANS?

stimulating effect

What is the function of the parasympathetic division of the ANS?

relaxing effect

What is the Enteric Nervous System (ENS)?

100 million neurons in walls of digestive tract that initiates and coordinates visceral reflexes locally without instructions from CNS

What are the key components of neurons?

Cell body (soma), dendrites, axons, telodendria, and axon terminals

What are the structural classifications of neurons?

Anaxonic, Bipolar, Unipolar, and Multipolar

What are the functional classifications of neurons?

Sensory, Motor, and Interneurons

What are the types of neuroglia in the CNS?

Astrocytes, Ependymal cells, Oligodendrocytes, and Microglia

What are the types of neuroglia in the PNS?

Satellite cells and Schwann cells

What is the function of astrocytes?

Maintain blood-brain barrier, provide structural support, regulate ion/nutrient/dissolved gas concentrations, absorb/recycle neurotransmitters, and form scar tissue after injury

What is membrane potential?

Electrical signals by ion movements

What is equilibrium potential?

Membrane potential at which there is no net movement of a particular ion across cell membrane

What is the function of the sodium-potassium exchange pump?

Ejects 3 Na+ for every 2 K+ brought in and stabilizes resting membrane potential

What is the resting membrane potential?

-70 mV

What is depolarization?

Membrane becomes less negative inside

What is repolarization?

Membrane returns to resting potential after depolarization

What is hyperpolarization?

Membrane becomes more negative than resting potential

What happens during the absolute refractory period?

The membrane cannot respond to further stimulation.

What happens during the relative refractory period?

The membrane can respond only to a larger-than-normal stimulus.

What is a synapse?

Specialized site where a neuron communicates with another cell

What are the types of Synapses?

Electrical and Chemical

What is the function of the Spinal Cord?

Carries sensory and motor information between the brain and most other parts of the body

What are the three specialized membranes surround the spinal cord?

Dura mater, Arachnoid mater, Pia mater

What is the function of meninges?

Protect the spinal cord. Carry blood supply. Continuous with cranial meninges.

What are the masses of gray matter within the central nervous system called?

nuclei

List the five components of a reflex arc

Sensory receptor, Sensory neuron, Information processing in CNS, Motor neuron, Effector

What are the four regions of the brain?

Cerebrum, Cerebellum, Diencephalon, Brainstem

What is the brainstem composed of?

Midbrain, Pons, Medulla oblongata

What is the function of the medulla oblongata?

Relays sensory information and Regulates autonomic functions

What are the three layers of cranial meninges?

Dura mater, Arachnoid mater, Pia mater

What is Proprioception?

Body position

What are the general senses?

Temperature, Pain, Touch, Pressure, Vibration, Proprioception

What are the special senses?

Olfaction, Gustation, Vision, Equilibrium, Hearing

What is a receptive field?

Area monitored by a single receptor cell

What is adaptation?

Reduction of receptor sensitivity in the presence of a constant stimulus

What are tonic receptors?

Always active and show slow adaptation

What are phasic receptors?

Normally inactive and Provide information about intensity and rate of change of a stimulus

What is the other name for for pain receptors?

Nociceptors

What is the the function of thermoreceptors?

temperature

What are the chemicals detected by chemoreceptors?

pH, CO2, O2

What are the three classes of mechanoreceptors?

Tactile receptors, Baroreceptors, Proprioceptors

What are Tactile receptors?

sensations of touch (shape or texture), pressure (degree of mechanical distortion), vibration (pulsing pressure)