Nervous system and hormones Flashcards
What is the nervous system
is a fast, short acting electronic signals
What are the two nervous systems
the central nervous system (CNS) – the brain and spinal cord
the peripheral nervous system – nerve cells that carry information to or from the CNS
What are neurons?
Neurones are long cells which carry electrical signals along their length
What is the central nervous system made up?
the brain and the spinal cord
How are neurons adapted to their function?
Name the stimuli…
Temperature, taste,smell, light and sound
What is the reflex action?
involves the stimulus, pressure receptor, spinal cord, the effector (muscle) which reacts.
stimulus → receptor → sensory neurone → association neurone → motor neurone → effector → response
What is the sensory neurone
This neurone carries the impulse from the receptors in the hand into the spinal cord.
What is the motor neurone
This neurone leaves the spinal cord via the ventral root and continues into the effector in the arm.
What is the advantage to the body of a reflex action?
Prevents harm and damage to the body.
What are hormones
Hormones are chemical messengers released by glands into the blood and carried to a target organ or organs.
What is homeostasis?
Homeostasis is the ability of the body to maintain an almost constant internal environment.
Give an example of homeostasis
controlling the concentration of glucose in the blood by the hormone insulin and controlling body temp.
What organ makes insulin?
Pancreas
What is diabetes?
is the inability to control blood glucose.
