Ch 13 Flashcards
4 types of tissue
Nervous
Epithelial
Muscular
Connective
3 functions of nervous system
Sensory
Integrative (process)
Motor
Sensory functions
Gathers information from inside of the body
And from outside environment(stimuli)
Nerves carry information to CNS(brain and spinal cord)
2 divisions of nervous system
CNS
PNS
Divisions of PNS
ANS(autonomic nervous system)(involuntary)(sympathetic, parasympathetic)
ENS(enteric NS)
SNS(somatic NS)(voluntary)
Motor function
Motor nerves convey information from CNS toward muscles and glads
Nervous tissue
Composed of 2 types of cells
Neuroglia(nerve glue) (most abundant)(CNS)…supports, protects, insulates, nourishes neurons (cares for) does not conduct nerves impulses
Neurons- transmission of electrical signals
Different shapes and sizes
3 parts of neurons
Dendrites, cell body, axon
Myelin sheath
Surrounds and protects nerve axon
Develops during 4th month of fetal life and continues through adolescence
White and gray matter
White matter=myelinated axons
Nerve impulses
3 parts
Polarization (resting)
Depolarization (stimulated)
Re-polarization(resting)
Weight of brain
Amount of oxygen
3 pounds
Consumes 20% of bodies oxygen supply
Primary source of energy for brain
Glucose
Hypoglycemia
Low glucose levels Mental confusion Dizziness Seizures Loss of consciousness Death
4 major areas of the brain
Cerebrum
Diencephalon
Brain stem
Cerebellum
Cerebrum
initiation and coordination of voluntary activity in the body.
Diencephalon
containing the epithalamus, thalamus, hypothalamus, and ventral thalamus and the third ventricle.
Distinct parts of diencephalon perform numerous vital functions, from regulating wakefulness to controlling the autonomic nervous system
Brain stem
the central trunk of the mammalian brain, consisting of the medulla oblongata, pons, and midbrain, and continuing downward to form the spinal cord.
regulates vital body functions such as cardiac and respiratory functions
Cerebellum
the part of the brain at the back of the skull. Its function is to coordinate and regulate muscular activity.
