Chapter 38 - Nervous And Sensory Systems Flashcards
Nerve net
A diffuse network of neurons that conducts impulses in all directions from a point of stimulus.
Nerve
Transmits impulses of sensation to the brain or spinal cord and impulses from these to the muscles and organs.
Cephalization
Evolutionary trend in which, over many generations, the mouth, sense organs, and nerve ganglia become concentrated at the front end of an animal, producing a head region.
Ganglia
Mass of nerve tissue, a group of nerve cells.
Two components of the central nervous system
The brain stem and spinal cord
Examples of reflex response
When the knee is struck and the leg swings involuntarily
Same situation for the elbow and forearm
What is the function of cerebrospinal fluid? Where is it found?
It acts as a cushion for our brain and spinal cord. Supplies nutrients to the nervous system. Also removes waste from the cerebral metabolism. It is found in the central canal and the ventricles.
Distinguish between grey and white matter.
Grey: contains the cell bodies, dendrites, and axon terminals of a neuron. This is where all the synapses are.
White: made of axons connecting different parts of grey matter to each other
What are the specialized support cells that have other functions, including myelination, structure support, and protection?
Glia
What’s makes up the peripheral nervous system (PNS)? What is the function of the PNS?
Everything except the cranial and spinal nerves are what make up the PNS. The function is to move information from the CNS to the rest of the body
What is dubbed the “voluntary nervous system”?
The motor system
What is dubbed the “involuntary?”
Autonomic nervous system
What would be the effect of stimulation by the sympathetic nervous system on heart rate?
It would raise the heart rate.
What would be the effect of stimulation by the parasympathetic nervous system on peristalsis?
It would ease it and make it rest
Which division of the autonomic nervous system would likely be activated if you learned that an exam you had forgotten about were to start in 5 minutes?
The sympathetic division would likely be activated. It mediates the flight or fight response. This means that the vasoconstriction of many blood vessels will occur.
Brainstem (pons,medulla)
Pons connects upper and lower parts of the brain, helps relay messages front the cortex to the cerebellum, also plays a key roll in REM
Medulla carries out and regulates life sustaining functions such as heart rate and breathing.
Cerebrum
The cerebrum is what is made up from the 4 cortexes (frontal, parietal, occipital, temporal)
Cerebellum
Responsible for balance and coordination of muscles and the body also responsible for fine motor functions.
Thalamus
Responsible for relaying information from the sensory receptors to proper areas of the brain where it can be processed
Hypothalamus
Responsible for behaviors such as hunger and thirst, as well as the maintenance of body temp. Also a key role in connections of the endocrine system and the CNS
Frontal lobe
Reasoning, planning, parts of speech, movement, decision making, problem solving.
Temporal lobe
Perception/recognition of auditory stimuli
Memory
Speech
Parietal lobe
Movement
Orientation
Recognition
Perception of stimuli
Occipital lobe
Visual processing
Mechanoreceptors
Receptors in skin and other organs to sense touch Tactile corpuscle Merkel nerve ending Lamellar corpuscle Bulbous corpuscle
Chemo receptors
Can detect changes in pH of spinal fluid
Located in the ventrolateral surface of the medulla oblongata
Taste buds
EM receptors
A neurological receptor that responds to light electricity and magnetism
Photoreceptors respond to light
Electroreceptors detect electrical energy
Thermoreceptors
Located in the dermis skeletal liver hypothalamus
Includes 2 types of receptors that signal innocuous warmth and cooling respectively
Pain receptors
3 types of pain receptor
Mechanical
Thermal
Chemical
What is perception?
The cognitive illusion are assumed to arise by interaction with assumptions about the worlds leading to “unconscious inferences”
Statocysts
A type of mechanoreceptor that functions in equilibrium in invertebrates through the use of statoliths which stimulates hair cells in relation to gravity
Statoliths
A grain or dense granule that settles in response to gravity and is found in sensory organs that function in equilibrium.
Auditory canals
Collects sound waves and channels them to the tympanic membrane.
Tympanic membrane
Membrane forming part of the organ of hearing, which vibrates in response to sound waves. It forms the eardrum between the outer and middle ear in higher vertebrates
Malleus, incus, stapes
Malleus a small bone in the middle ear that transmits vibrations of the eardrum to the incus, the incus is an anvil shaped bone in the middle ear, transmitting vibrations between the malleus and stapes, the stapes is stirrup shaped and transmits sound from the incus to the cochlea.
