b2.1 the nervouse system Flashcards
(16 cards)
What is the role of sensory receptors?
Sensory receptors detect specific stimuli (like light, sound, heat) and convert them into electrical impulses.
What types of sensory receptors are there?
Examples include photoreceptors (light), mechanoreceptors (pressure/touch), thermoreceptors (temperature), and chemoreceptors (chemicals).
What is the function of the central nervous system (CNS)?
The CNS processes information from sensory neurons and coordinates responses by sending signals via motor neurons.
What is the role of the myelin sheath on neurons?
It insulates the neuron and speeds up the transmission of electrical impulses.
How do motor neurons connect to muscles?
Motor neurons transmit impulses to muscles, causing them to contract and produce movement.
What happens at a neuromuscular junction?
Neurotransmitters are released from a motor neuron to stimulate a muscle to contract.
Why is the reflex arc faster than normal responses?
Because it bypasses the conscious brain by routing impulses through the spinal cord for an automatic response.
What is the master gland in the human body?
The pituitary gland.
It controls the activity of other endocrine glands by releasing hormones that regulate growth, reproduction, and metabolism.
What is adrenaline released by?
Adrenal glands
What effect does adrenaline have on heart rate?
Increases heart rate to pump blood faster
How does adrenaline affect airways?
Dilates airways for more oxygen
What does adrenaline do to glycogen?
Converts glycogen to glucose for quick energy
What is negative feedback?
Negative feedback reverses changes in the body to keep conditions stable, like insulin lowering high blood sugar.
How does a synapse transmit an impulse?
Neurotransmitters are released into the gap between neurons, cross it, and bind to receptors on the next neuron to pass the impulse on.
How does the pancreas respond after a meal?
The pancreas releases insulin to lower blood glucose levels.
Excess glucose is converted to glycogen for storage.
What does the pancreas release between meals?
The pancreas releases glucagon.
Glucagon converts glycogen back into glucose to raise blood glucose levels.
