PNS and endocrine
Anatomy of the Spinal Cord-connection between the brain and brainstem to the rest of the body, 31 pairs of spinal nerves
Cross Section Anatomy- Two grooves divide spinal cord
Gray Matter
White Matter
Peripheral Nerves-Is made up of 31 pairs of spinal nerves and 12 pairs of cranial nerves
Spinal Nerves-Allow the brain and body to communicate
Cranial Nerves
Coverings
Autonomic Nervous System-branch of PNS
Endocrine System-Consists of endocrine glands located throughout the body
Hormones-chemical messengers, produced by endocrine cells, that travel in blood and influence certain cells elsewhere in the body
Hormonal Mechanism and Control
Endocrine Organs of the Brain
Hormones of Pituitary Glands
Cervical Enlargement-C4-T1-Nerves to and from upper limbs
Lumber Enlargement-T9-T12-Nerves to and from lower limbs
Conus Medularis-end of the spinal cord
Cauda Equina="horse's tail" divides into nerves that leave at lower levels
Anterior Median Fissure- deeper
Posterior median sulcus
Lateral Horns- Located on the side cell bodies of motor neurons to cardiac, and smooth muscle and glands
Anterior/Ventral Horns (Motor)- Cell bodies of motor neurons to skeletal muscle
Posterior/Dorsal horns (Sensory)- located in the back
Central Canal-center of gray matter commisure; continuous with fourth ventricle
Descending (Motor) Tracts-Impulses from brain
Ascending (Sensory) Tracts-impulses toward brain
Mixed nerves-carring both sensory and motor information
Posterior/dorsal roots- contain sensory fibers whose cell bodies are located in dorsal root ganglion
Anterior/Ventral roots-contain motor axons and conduct impulses from brain and cord to periphery
VI-Abducens-lateralrectus eye muscle abducts the eye
VII-Facial-motor to muscles of facial expression; sensory-taste
V-Trigeminal-3 branches- motor-chewing;sensory-skin of face
VIII-Vestibulocochclear-sensory-hearing and equilibrium (balance)
IV-Trochlear-superior oblique muscle of eye
IX-Glossopharyngeal-motor secretion of saliva; sensory-taste,regulation of blood pressure, and proprioception of muscles involved with swallowing
III-Oculomotor-mostly motor function-most of muscles of eye, eyelid, and pupillary constriction
X-Vagus-motor-smooth muscle contraction and relaxation, secretion of digestive fluids; heart, lungs-parasympathetic innervation; sensory from visceral organs it supplies and proprioception
II-Optic-Arises from retina of the eye and functions in vision
XI-Accessory-motor:swallowing and movements of head;sensory-proprioception
I-Olfactory-Sensory nerve that functions in sense of smell
XII-Hypoglossal-motor-movement of tongue during speech and swallowing:sensory-proprioception
Perineurium-surrounds fascicles (bundles nerve fibers)
Epineurium-surrounds entire nerve
Endoneurium-surrounds individual neuron
Sympathetic- fight or flight, E- exercise, excitement, emergency, embarrassment
Parasympathetic-daily body functions, feed or breed, D-digestion, defecation, and diuresis (Urination)
Negative Feedback-occurs when there is a drop in the level of a hormone, triggers a chain reaction of responses to increase hormones in the blood
Endocrine Glands of the Body
Pancreas-controls blood sugar levels
Insulin-decrease blood glucose
Thymosin Hormones-stimulates the development of the T-cells involved in the immune response
Adrenal Cortex-outer layer
Parathyroid Hormone (PTH)-increases blood calcium levels
Glucocorticoids or cortisol-responds to stress or injury and releases anti-inflammatory
Calcitonin-decrease blood calcium levels
Adrenal Medulla-inner layer
Thyroid Hormone(Thyroxine,T3 and T4)-control the basal metabolic rate
Epinephrine (adrenaline)-stimulates the fight or flight response
Anterior lobe-makes and releases hormones under the control of the hypothalamus
Posterior lobe-stores and secretes hormones that are made in the hypothalamus, such as antidiuretic hormone and oxytocin,and releases them to the rest of the body as necessary
Pituitary gland=master gland that signals other glands to produce their hormones when needed
Antidiuretic hormone (ADH)-regulates fluid balance by increasing body fluid volume and decreasing urine output
Hypothalamus-produces hormones that stimulates the pituitary gland
Oxytocin-stimulates contraction of the uterus during labor and milk, or ejection from alveoli
Melatonin-controls sleep cycles, alertness, and temperature
Human growth hormone (HGH)-stimulates growth during infancy and puberty
Prolactin-initiates and maintains milk secretion
Adrehocorticotopic hormone (ACTH)-stimulates the adrenal gland to release cortisol
Thyroid stimulating Hormone (TSH)- control basal metabolic rate releasing thyroxine
Luteinizing hormone (LH)-both involved with development of ovaries and testes
Melanocyte stimulating hormone (MSH)-stimulates production of melanin in the skin
Follicle stimulating hormone (FSH)-stimulates egg maturation in the ovary and release sex hormones