sci_mod16 Flashcards
The system of nerves which carries instructions from the CNS to the body’s smooth muscles, cardiac muscle and glands
Autonomic nervous system
The system of nerves which carries information from the body’s receptors to the CNS
Sensory nervous system
The system of nerves which carries instructions from the CNS to the skeletal muscles
Motor nervous system
What are the two main types of cells in the human nervous system?
Neurons and neuroglia are the two principal kinds of cells in the human nervous system.
What do dendrites do?
Dendrites carry electrical signals to the cell body.
What do axons do?
Axons carry electrical signals away from the cell body.
What is a synapse?
A synapse is a small gap between the axon of a neuron and the receiving end of another cell.
Explain how a signal crosses from the axon of a neuron to the receiving cell.
When the electrical signal reaches the end of the axon, neurotransmitters are released which travel across the synapse. Once they reach the receiving cell, they create a new electrical signal.
What is the function of neuroglia?
Neuroglia support the neurons by performing tasks which make it possible for the neurons to do their job.
A nerve runs down the leg, carrying signals to the foot. Is it a part of the PNS or the CNS?
The nerve is a part of the PNS. The PNS contains all nerves that run off of the spinal cord. If it is in the leg, it is off the spinal cord.
What two main structures make up the CNS?
The CNS is made up of the brain and the spinal cord.
What two things protect the brain?
The skull and the cerebrospinal fluid protect the brain.
What protects the spinal cord?
The vertebral column protects the spinal cord. You could also say “the backbone.”
What is the brain’s gray matter composed of?
Gray matter is made up mostly of neuron cell bodies.
What is the brain’s white matter composed of?
White matter is made up mostly of the axons of neurons.
What is the function of the corpus callosum?
The corpus callosum allows the two sides of the brain to communicate with one another.
What does the cerebellum primarily control?
The cerebellum is mostly in charge of voluntary muscle movements, especially fine movements.
What part of the brain deals mostly with the higher level thinking skills?
The cerebrum is in charge of most higher level thinking skills.
Do the two sides of the brain do exactly the same things?
The two sides of the brain do not do exactly the same things. The left side of the cerebrum, for example, tends to be responsible for speaking, logic, and math. The right side is more involved with spatial relationships, recognition, and music.
What side of the PNS does the left side of the brain control?
The left side of the brain controls the right side of the PNS.
What is the blood-brain barrier and why is it important?
The blood-brain barrier is a system that insulates the brain from the blood. It is important because many of the chemicals in our blood are toxic to brain cells. The blood-brain barrier selectively transports “good” chemicals into the brain and leaves the “bad” chemicals in the capillaries, insulated from the brain.
What does the sympathetic division of the autonomic nervous system do?
The sympathetic division increases the rate and strength of the heartbeat and raises the blood pressure. It also stimulates the liver to release more glucose in the blood, producing quick energy for the “fight or flight” response that we experience when we are frightened or angry.
What does the parasympathetic division of the autonomic nervous system do?
The parasympathetic system slows the heart rate and lowers the blood pressure. In addition, it takes care of certain “housekeeping” activities such as causing the stomach to churn while it is digesting a meal.
What are the four basic tastes that we can detect?
Humans detect four basic tastes: salty, sour, sweet, and bitter.
