Post on 28-May-2019
transcript
Unit 2
The Nervous, Limbic, and Endocrine systems
Parts of the Nervous System
� Central Nervous System (CNS)� Brain and spinal cord
� Peripheral Nervous System (PNS)� Carries messages to and from CNS
Central nervous system
Peripheral nervous system
Sympathetic and parasympathetic divisions of the nervous system
Split brain operation—procedure used to reduce recurrent seizures of severe epilepsy
Corpus Callosum—thick band of axons that connects the two cerebral hemispheres
axon terminal
dendrite receptors
How Neurons Work
� Input comes in from/goes to part of the body� You want to move your arm
� An electrical impulse is sent down the axon to a nerve ending
� The electrical impulse stops at the synapse� Neurotransmitters (for movement) are released by
the axon terminal into the open space� Once in the open space the chemicals float to the
dendrite receptor for movement� The excited dendrite sends an electrical impulse to
the next cell and so on� The electrical impulse travels ends at muscle
receptors and your arm moves (120 yards / sec)
Neurotransmitters
� Acetylcholine� Regulates body processes such as movement� Memory � In Alzheimer’s disease patients it often is not working
properly� Dopamine
� Involved in the CONTROL of bodily movements� Parkinson’s disease patient have a shortage of it
� Endorphins� Relieve pain and increase our sense of well being� Creates the “runner’s high”
The Limbic System
� Hypothalamus� Amygdala� Hippocampus
� Contains structures involved in basic emotions, motivations, and memory
� Amygdala� Emotional responses like aggression, rage, and
fear
� Hippocampus � Enables us to form memories (not memory
storage)� If there’s damage to the hippocampus, we can’t
make new memories
The Limbic System
Hypothalamus� Contains nuclei involved in a variety
of behaviors� sexual behavior� hunger, thirst� sleep� water and salt balance� body temperature regulation� circadian rhythms� role in hormone secretion
Endocrine System: hormones
� Pituitary gland� Master gland� Growth hormones
� Thyroid� Regulates your metabolism (speed of body processes)
� Adrenal Glands� Secrete adrenaline. Prepares the body for emergencies
� Gonads: � sex glands make eggs or sperm for reproduction� Ovary in females (estrogen)� Testis in males (androgen)
Endocrine System