Unit 4 Lectures Flashcards
What are the 2 main divisions of the nervous system?
Central Nervous system and peripheral nervous system
What are the general divisions within the peripheral nervous system?
Sensory (afferent) and Motor (efferent)
What are the divisions of the motor division?
Somatic and Autonomic
What are the divisions of the autonomic?
Sympathetic (fight or flight)
Parasympathetic (rest and digest)
What is the difference between neurons and neuroglia?
Neurons are conductors while neuroglias are supporters of the conduction
What is the function of the neuroglia?
They protect, repair, regulate and aid neurons and their neuronal impulse transmission
What is the relationship between tumors and neuroglia?
Tumors can be caused by uncontrolled neuroglia growth
What are the Central nervous system neuroglia?
Astrocytes (form blood brain barrier)
Microglia (macrophages that eat pathogens)
Ependymal Cells (help make CSF)
Oligodendrocytes (form myelin sheath)
What are the peripheral nervous system neuroglia?
Schwann Cells (form myeline around neurons) Satellite cells (protect neuron bodies and ganglia by regulating environment)
What is the difference between myelinated and unmyelinated axons?
Myelination: speeds up rate of impulse conduction
What are some general features of neurons?
- transmit impulses
- highly sensitive to external changes
- high metabolic rate
- cannot divide
- extreme longevity
What is the synaptic terminal?
The knobs at the end of theneuron that form synapses and release neurotransmitters
What is the general track of the neuron impulses?
- begins at dendrites, goes through the cell body, down the axon, ends at terminal buttons
Types of neurons?
Anaxonic
Bipolar (special senses)
Pseudounipolar (sensory)
Multipolar (most common)
White matter vs gray matter?
White matter is due to myelination of fibers
Gray matter indicates we have unmyelinated fibers
What are nerves made up of?
Axons and dendrites bundled together.
What are the developing regions of the brain in a 3 week embryo?
Forebrain (proencephalon)
Midbrain (mesencephalon
Hindbrian (rhomboencephalon)
What are the adult regions of the brain (developed)?
Forebrain is made of telencephalon and diencephalon
Midbrain is made of mesencephalon
Hindbrain is made of metencephalon and myelencephalon
Telencephalon develops…
cerebrum
Diencephalon develops…
thalamus and hypothalamus
Mesencephalon develops
cerebral peduncle and corpora quadrigemina
Metencephalon develops…
pons and cerebellum
Myelencephalon develops…
medulla oblongata
3 meninge layers of the brain
Dura mater
Arachnoid
Pia mater
What are the 2 layers of the dura mater?
Endosteal and meningeal
What is the function for the Cerebral spinal fluid?
protect, cushion and nourish the brain and spinal cord (remove waste)
What does the choroid plexus do?
It produces the cerebral spinal fluid since it is composed of ependymal cell and capillaries
Where is the CSF found?
brain, spinal cord, and ventricles
What is hydrocephalus?
This is when our arachnoid villi are blocked and can cause back flow of CSF
What is the function of the cerebrum?
Store memory, conscious though and learning
What is the purpose of the frontal lobe?
Control of skeletal muscles
Prefrontal cortex is responsible forintellect. learning, personality ,etc
What is the function ofthe parietal lobe?
Touch, pressure, pain, temp perception
What is the function of the occipital lobe?
Vision
What is the function of the temporal lobe?
Sound and smell
What is the function of the thalamus?
Sensory relay station to the cerebral cortex
What is the function fo the hypothalamus?
Control center for autonomic NS and endocrine system. Controls emotions and sleep-wake cycle
What is the function of corpora quadrigemina?
Visual and auditory reflexes
What is the function of the cerebellum?
Receives information from cerebrum, inner ear, and body
Coordinate body, equilibrium
What is the function of the pons?
Links the cerebellum with brain and spinal cord
Respiratory rhythm
What is the function of the medulla oblongata?
Contains centers for autonomic functions
All cranial nerves attaced to brainstem except?
Olfactory
What is the space between meninges and bone of vertebra called?
Epidural space - contains fat, blood vessels, ct
What is the end of our spinal cord?
Conus medullaris
What is the cauda equina?
It has our spinal nerves gorwing out of vertebrae
What is the filum terminale? its function?
It comes out of the cauda equina and it anchors our spinal cord down (prevent superior)
What anchors our spinal cord laterally?
Denticulate ligament
What are denticulate ligaments made of?
Pia mater and attach to arachnoid
why would a lumbar puncture be performed?
To obtain a sample of CSFand test health of our nervous system
Spinal cord sensory impulses to the brain are…
Afferent and ascending
The spinal cord motor impulses are …
Efferent and descending
What is the parts of the spinal cord gray matter?
Lateral, anterior, posterior horn, gray commissure
Impulse from lateral horn is responsible for what motor function?
Visceral
Impulse from anterior horn is responsible for what motor function?
somatic
Impulse coming in goes through which structures?
It will go thorugh dorsal ganglion, dorsal root, dorsal horn
Impulse from dorsal horn is responsible for what motor function?
both somatic and visceral sensory
D.A.V.E means?
dorsal (horn) is afferent (sensory)
Ventral (horn) is efferent (motor)
What are the parts of the white matter in the spinal cord?
lateral column
Anterior column
posterior column
What are the parts of reflex arc?
- receptors are stimulated
- Sensory impulse sent to the spinal cord
- Impulse travels to interneuron of spinal cord
- Impulse comes back through motor neuron
- will stimulate or inhibit the cell or organ
All spinal nerves carry sensory and motor neurons except..
the phrenic nerve
What forms spinal nerves?
The fusion of ventral and dorsal roots
The dorsal ramus nerves innervate what region of the body?
The back
T1- L2
The ventral ramus nerves innervates what region of the body?
Sides and front (all plexuses are here)
How many nerve plexus do we have?
4, the thoracic dont form a network
What is the difference between lumbar and sacral plexus?
Lumbar plexus is anteriorside of leg
Sacral plexus is posterior side of leg
What are dermatomes?
Areas of the body that are controlled by a specific nerve
What neurotransmitter does our somatic spinal cord nerves have?
acetylcholine (excite skeletal muscle)
What neurotransmitter does our visceral motor divsion (spinal cord)?
Acetylcholine and norepinephrine (excite or inhibit)
What are some functions of the autonomic nervous system?
Regulate body temp
Coordinate cardiovascular respiration, digestion, reproduction,etc
Sympathetic is also known as
Thoracolumbar
Parasympathetic is also known as
Craniosacral
What is the function of sympathetic chain ganglia?
send signals to the rest of the body (after ventral ramus)
What are preganglionic neurons?
Thisis one ofthe first neurons that allow electrical signal from CNS to organs
Preganglionic neurons general strucutre?
Branch off spinal cord
Cell bodies are in lateral gray orn
Axons enter ventral root
In Sympathetic what is the Preganglionic vs postganglionic length?
Preganglionic are short
Postganglionic are long
What neurotransmitter is released at the sympathetic division?
Norepinephrine
What is the function of the adrenal gland?
It releases epinephrine and norepinephrine
It has a long lasting effect
Where do we find preganglionic neurons?
In brainstem and sacral segments
In parasympathetic what is the length for pregnaglionic and postganglionic neurons?
long preganglonic
Short postganglionic
What is released in parasympathetic?
Acetylcholine
Parasympathetic vs sympathetic responses?
Parasympathetic: constrict pupils, increase saliva, decrease heart rate, increase digestion
Sympathetic:
dilated pupils, decrease saliva, increase heart rate, decrese digestion
What must occur for action potential to occur at receptors?
Stimulus must be strong enough (meet the threshold
What is sensory adaptation?
It is when the threshold changes. EX: going in a pool may be cold at first but your bodies threshold changes and gets used to it.
General receptor vs special sense receptors?
General: all throughout body (skin, muscles, organs, etc)
Special Sense: concentrated in complex organs
What is receptive field?
That is when our sensory neurons collect impulses from multiple receptor within a field.
The smaller the receptive field, the more accurate area of stimulus
What is a mechanoreceptor?
Receptor that detects physical change (touch sensation, etc)
What are the types of mechanoreceptors?
Propioreceptor: detects position of body in space
Tactile receptors: poking skin
What is a thermoreceptor?
Detection of heat or cold (change in temperature)
What is a chemoreceptor?
Detects chemical changes in taste, smell, etc
What is a photorecceptors?
Detects photons of light (only in eye)
What is a nociceptor?
A receptor that detects pain and tissue damage
Where are most of our receptors found?
In the eye (70%)
What is the difference between cones and rods?
Cones and rods are both photoreceptors
Cones: detect color (red green and blue)
Rods: detect light and dark
What are the 3 layers of the eye?
Fibrous tunic
Vascular Tunic
Nervous Tunic
What is part of the fibrous tunica?
Cornea and Sclera
What is part of the vascular tunic?
Choroid (absorbs light)
Iris (adjusts light)
Lens (focuses image on retina by getting pulled)
Ciliary body (adjusts shape of lens and secretes aqueas humor)
Ciliary body secretes __________ and the _________ absorbs it
Ciliary body secretes aqueous humor
Canal of Schlemm absorbs the aqueous humor
What is part of the nervous tunic? (retina)
Optic disc (blind spot) and the Fovea (focal point that has cones)
What are the layers of cells in the retina?
Ganglion, bipolar, rods and cones
We have a pigmented retina
Which glands produce wax of ear?
Ceruminous glands (it has anticrobial qualities)
What are the ossicles of the ear?
Malleus, incus, stapes
Where is the inner ear embedded into?
The temporal bone
What is the hearing sense? What is the equilibrium?
Hearing: cochlea
Vestibule: equilibrium `
What type of receptor is hearing?
Mechanoreceptor
What is the beginning of the hearing tracing?
external ear, middle ear bones, fluid in inner ear, bend receptors in cochlea
Where are equilbrium receptors found?
In the semicircular canals and vestibule
What are the parts of the vestibule?
Utricle and Saccule
What is static equilibrium?
When standing still and you tilt your head.
This allows equilirbium because the crystals in the vestibule (utricle and saccule) send signals for equilibrium when the head is tileted
What is dynamic equilirbium?
It occurs within semicricular ducts and there is endolymph that hits mechanoreceptors that send signals for equilirbium
What receptors are used for smell?
Chemoreceptors
What condition must be for chemoreceptors?
They MUST be in fluid
What is the only special sense that does not synapse in thalamus?
Olfaction because it is not attached to brain
What receptors are used for taste?
Chemoreceptors
Impulses for taste are processed where?
Parietal lobe
What are the 3 different taste buds?
Circumvallate papillae
Fungiform paillae
Filiform papillae (spiky)
Where are the taste cells found?
In the taste buds
What 3 cranial nerves innervate the tongue for taste?
Facial nerve, Glossopharyngeal and the vagus
What is the difference between exocrine and endocrine
Exocrine: have duct, produce secretion into duct, prduct empited into epithelial surface
Endocrine: have no duct, form hromones, hormonmes are diffuse into blood vessels, hormones have target organ
What is the differences between nervous system and endocrine system?
Nervous: short term effect, specific targeted organs, neurotransmitter released at synapse, immediate response and recovery
Endocrine: long term effect, general target organs, hormones released into blood, slow response and recovery
Neuroendocrine organs?
Hypothalamus, pituitary gland, adrenal gland and pancreas
How is the hypothalamus neuroendocrine?
Endocrine: regulates endocrine system, releases hormones, synthesizes hormones, etc
Nervous: control emotions, regulate body temp, control day-night cycle
How is the pituitary neuroendocrine?
Endocrine: The pituitary gland as the adenohypophysis which produce and release hormones
Nervous: the neurohypophysis is made from brain
How is the adrenal gland neuroendocrine?
The adrenal cortex secretes hormones
The adrenal medulla releases epinephrine and nor epinephrine (adrenaline)
What does the hypothalamus release?
Antidiuretic hormone (ADH) and oxytocin (triggers uterus to contract)
What does ADH target?
Kidneys
What does the anterior pituitary gland release?
Growth hormon, prolactin, FSH, LH, TSH, ACTH
What is pituitary dwarfism?
this is when the gland does not produce normal Growth horomones
What is gigantism?
High growth hormone before puberty
What is acromegaly
high GH but affects hands, feet, organs
What hormones are released by thyroid gland?
Thyroxine and calcitonin
What does thyroxine do?
increases metabolic rate, oxygen, nutrient consumption, etc
What does calcitonin do?
decreases blood calcium level and increases bone production
What is hypothyroidism?
Low thyroxine and the gland can enlarge (big throat)
If you have this for a long time, it can lead to myedema which can lead to brain damage and death
Short term stress vs long term stress
Adrenal medulla: short term
Adrenal cortex: long term (corticoids)
