Nervous System, Sleep Flashcards
Nervous System:
Provides ____ responses by integrating ____ and ____ information.
Provides “rapid” responses by integrating “internal” and “external” information.
Cnidarian nervous system
diffuse nerve net
Echinoderm nervous system
nerve ring
Cephalization
clustering of sensory neurons and interneurons at anterior end
The human brain has ___ # nerve cells
100 billion neurons
Parts of a neuron: Dendrites
Receives signals from other neurons
Parts of a neuron: Maintains cell health
Cell body
Parts of a neuron: Axon hillock
generates signal
Parts of a neuron: Axon
Sends signal to terminal branches
Parts of a neuron: Myelin sheath
Nourishes, insulates and protects axon, also allows for a special function:
Parts of a neuron: Synaptic terminals
sends signal to other cells
Central Nervous System (CNS)
Information processing: Brain AND Spinal Cord
Peripheral Nervous System (PNS)
Non-central nervous system
Afferent Neurons/System
Involved in SENSING stimuli
Efferent Neurons/System
Controls REACTION to those stimuli determined by the central nervous system beforehand.
What are two subcategories of the Efferent System?
The autonomic nervous system, and the motor system.
3 subcategories of the Autonomic Nervous System
The Sympathetic, Parasympathetic, and Enteric divisions
Autonomic Nervous System: Sympathetic Division– What increases, and what decreases?
Controls fight or flight response, arousal, energy, increased heart rate, epinephrine, and LOWERED digestion.
Autonomic Nervous System: Parasympathetic Division– What increases, and what decreases?
Calming. Lowers heart rate and epinephrine, but INCREASES digestion.
Autonomic Nervous System: Enteric Division–
Controls digestive tract, pancreas, gallbladder, persistalsis
Form matches function: Sensory Neurons
Very long axons
Form matches function: Motor Neurons
about average size and branching
Form matches function: Interneurons
Exist in brain, extremely branched
Glial Cells
General name for brain supporting cells
How many glial cells for every neuron?
at least 50
Oligodendricytes: Which system, function
Myelination of axons to increase signal speed in the CENTRAL NERVOUS SYSTEM
Schwann Cells: Which system, function
Myelination of axons to increase signal speed in the PERIPHERAL NERVOUS SYSTEM
Astrocytes 2 functions
provide metabolic support to neurons and create a blood brain barrier.
What is the function of the blood brain barrier?
allows small particles to pass through, but not bacteria or large molecules
Membrane Potential
voltage e- difference across the plasma membrane.
Resting Potential Differences
The inside of the cell is MORE NEGATIVE by about 70mV.
Resting Potential: which ions are located inside cell?
High amounts of K+ and A-
Resting Potential: which ions are located outside the cell?
High amounts of Na+ and Cl-
Membrane is selectively _____ due to ____ ___ ___ ___.
Membrane is selectively permeable due to active transport ion channels.
3 main types of membrane proteins
Sodium Potassium Pumps, Potassium channels, and sodium channels.
Function of a Sodium Potassium Pump
Pushes Na+ ions out of cell, and K+ ions into the cell. (proponent of Resting Potential)
Graded Potential
amplitude depends on strength of the stimulus