-
Central Nervous System
- brain and spinal cord
- sorts sensory information
- generates thought and emotions
- forms and stores memories
- stimulates muscle contractions
- stimulates glandular secretions
-
Peripheral Nervous System
- connects sensory receptors, muscles, and glads to the CNS
- Afferent Neurons (sensory)
- Efferent Neurons (motor)
-
Afferent Neurons (Sensory)
conduct nerve impulses from sensory receptors toward the CNS
-
Efferent Neurons (Motor)
conduct nerve impulses away from the CNS to muscles and glands
-
Autonomic Nervous System
- sensory neurons from viscera to CNS
- efferent neurons to smooth muscle, cardiac muscle, and glands
- unconscious control
- two divisions: sympathetic division-stimulatory effect (on), parasympathetic division-inhibitory effect (off)
-
-
Dendrite
detects signals (efferent)
-
-
Axon
- long, thin, cylindrical processes
- may be mylinated (insulated)
-
Synapse
- send message to the next cell
- release neurotransmitters to carry signal to the next nerve
-
Neuroglia
- cells to nurture neurons
- types of neuroglia found in the CNs: astrocytes, oligodendrocytes, microglia, ependymal
-
Astrocytes
- star-shaped cells
- form a blood brain barrier, link neurons and blood vessels
-
Oligodendricytes
- small cells
- support neurons and make a lipid and protein covering (myelin sheath) in the CNS
-
White Matter
myelinated axons
-
Gray Matter
nerve cell bodies, dendrites, ganglia, and axon terminals
-
Actions Potential
- resting potential (Na+ out and K+ in)
- stimulus reaches threshold potential
- Na+ channels open; K+ channels still closed
- Na+ channels close; K+ channels open
- undershoot: K+ channels close slowly
-
Reflex Arc
- fast, predictable, automatic responses
- sensory neuron→interneuron→motor neuron
-
Cerebrum
most of the cranium with right and left hemispheres
-
Cerebellum
the posterier-inferior portion of the brain
-
Brain Stem
the medulla oblongata, the pons, and the midbrain
-
Diencephalon
thalamus and hypothalamus
-
Meninges
- brain protection
- dura mater: outer layer
- arachnoid mater: middle layer
- dia mater: inner layer
-
Cerebrospinal Fluid
- nourishes and protects brain and spinal cord
- continuouly circulated by cilia
-
Front Lobe
- motor areas voluntary movement
- carry on high level intellectual processing
-
Parietal Lobe
- sensory areas interpret sensations like touch , pressure, and pain
- understanding speech
-
Temporal Lobe
- hearing and balance
- interpret sensory experience
-
Occipital Lobe
- visual processing an interpretation
- visual images with sensory experience
-
Gyrus (Gyri)
ridges on brian
-
Sulcus (Sulci)
grooves in brain
-
Medulla Oblongata
- breathing
- heart rate
- coughing, vomiting, swallowing, and hiccuping
-
Pons
- lies superior to the medulla oblongata
- helps control respiration
-
Midbrain
- superior to the pons
- connects the brain stem to the diencephalon
-
Thalamus
- 80% of the diencephalon
- principle relay station between the various sections of the brain
-
Hypothalamus
- small portion located below the thalamus
- the main regulator of homeostasis
- thirst, hunger, satiety (feeling satisfied)
-
Alzheimer's Disease
- 11% of population
- dementia due to atrophy of neurons of the frontal and occipital lobes
-
Amyotropic Lateral Sclerosis (ALS of Lou Gehrig's Disease)
- degeneration of the motor neurons of the spinal cord, medulla, and cortex
- no known cure
-
Bacterial Meningitis
- infection of the meninges
- symptoms: severe headaches, fever and even death
- more common in college students
-
Cerebral Palsy
- loos of muscle control
- damage to the motor areas of the brain during fetal development, during birth and during infancy
-
Epilepsy
- short, recurrent, periodic, neuronal malfunction
- seizures-involuntary skeletal muscles contractions
-
Multiple Sclerosis
- the progressive destrucion of the myelin sheaths of neurons in the CNS
- "short circuits" nerve transmission
- cause is unknown, no cure
-
Parkinson's Disease
- over 60, loss of nerve function
- tremors (shaking), muscle weakness, and a peculiar gait
-
Cerebral Vascular Accident (Stroke)
- slurred speech, loss of or blurred vision
- Ischemic CVA: due to lack of blood supply
- Hemorrhagic CVA: due to the rupture of a blood vessel
-
Fibrous Tunic
- thick, outermost layer of the eyeball
- sclera: the posterior "white" portion
- cornea: the anterior transparent portion of the fibrous tunic
-
Vascular Tunic
- supplies blood to the eye
- choroid: posterior, thin, dark brown membrane lines the internal sclera
- ciliary body: anterior, thick portion of smooth muscle fibers
- iris
- lens
-
Iris
contraction of smooth muscle to dilate or constrict pupil
-
Lens
alteration of the shape of the lens
-
Nervous Tunic
- inner layer of eye
- retina: a thin fragile layer of neurons and photorecptors
- optic nerve: axons and ganglion cells to transmit images to the occipital lobe
-
Rods
eleongated cylindrical dendrites that are sensitive to light
-
-
Pituitary Gland
- pituitary gland is found near the diencephalon of the brain
- often called the master gland because it secretes hormones that control other endocrine glands
- hGH, TSH, ACTH,
-
Thyroid Gland
- located just below the larynx with its lobes lying on either side of the trachea
- secretes thyroxine
-
Cortisol
- a family of stress hormones
- made in adrenal glands
- peaks shorty before dawn
-
Adrenal Medulla
- inner region of the adrenal glands
- two sets of hormone producing cells
- under the control of the ANS
-
Pancreas
- a flattened oblong organ located just posterior and slightly inferior to the stomach
- is both an endocrine and exocrine gland
-
-
Insulin
absorbing glucose
-
Diabetes Mellitus
a group of disorders that lease to an elevation of blood glucose (hyperglycoma)
|
|