Nervous System Flashcards
What is a neuron?
A basic cell of the nervous system which carries impulses around the body
What’s a receptor?
A special sensory cell that detects changes in the environment
What is a nerve?
A bundle of hundreds or thousands of neurons
What is the central nervous system?
Your Brain and spinal cord (used for processing information)
What is a sensory neuron?
A neuron which carries impulses from a sensory organ to the central nervous system
What’s an effector organ?
Muscles and glands that respond to impulses from the nervous system
What is a motor neuron
A neuron that carries impulses from the central nervous system to the effector organs
What is a reflex?
A rapid automatic response of the nervous system that doesn’t involve conscious thought
What is the reflex arc?
The sense organ, densely neuron, relay neuron, motto neuron, and effort or organ which brings out a reflex action
What a synapses?
The gap between neurons where the transmission of information is chemical rather than electrical
What are the root like appendages callers around the cytoplasm and nucleus of a nerve cell?
Dendrites
What covers the nucleus on a nerve cell?
Cytoplasm
What is the long tail called on a nerve cell?
The axon
What covers the axon and protects are body from electrical impulses in a nerve cell?
The myelin sheath
What are the root like appendages at the end of the axon on a nerve cell called?
Dendrites
Describe thermoregulation (high body temperature)
Body temp high
Hypothalamus in brain detects change
Hairs flatten so air isn’t trapped to insulate
Sweat absorbs heat
Vasodilation (widening blood vessels)
Body temperature decreases
Describe thermoregulation (low body temp)
Body temperature low
Hypothalamus detects change
Hairs rise to trap air
Shivering makes heat
Vasoconstriction (vessels narrow)
Body temperature increases
Describe osmoregulation (water high)
Over hydrated
Pituitary gland releases less hormone ADH
Kidneys reabsorb les water and ions
Excess water excretes (urine)
Less water taken in through drink food and respiration
Water ion balance decreases
Describe osmoregulation water balance low
Dehydration
Pituitary gland releases more hormone ADH
Kidneys reabsorb more water ions
Less water excreted in urine
More water taken in through drink food and respiration
Water and ion balance increases
Describe how our bodies deal with high glucose levels
Glucose levels high
Insulin released by pancreas, inhibiting glucagon
Glucose taken in by tissue cells for energy
Glucose take in by liver to be stored as glycogen
Blood glucose levels fall
Describe how our body deals with low glucose levels
Glucose levels low
Glucagon released by pancreas, inhibiting insulin
Glycogen in liver broken down into glucose and released into blood
Blood glucose levels rise
Describe the sensory arc
Stimulus v Sensory receptor v sensory neuron v Relay neuron v Motor neuron v Motor end plate v Effector organ
What is an impulse?
An electrical signal carried along the neurons
