B3.1 - The Nervous System Flashcards
What are the 2 types of nervous system?
CNS and PNS.
What does CNS stand for? And what body parts does it travel through?
Central Nervous System. The brain and spinal cord.
What does PNS stand for? And what body parts does it travel through?
Peripheral Nervous System. All other body parts.
What causes a stimulus?
A change in the environment.
What are all the steps in a reflex arc?
stimulus - sensory receptors - sensory neurone (synapse) - relay neurone in CNS (synapse) - motor neurone (synapse) - effector (muscle or gland) - response
What are the parts in a basic neurone?
dendrites, dendron, myelin sheath, cell body (+ nucleus), axon, axon terminal
What is the definition of a neurone?
Neurone: a specialized cell that transmitts nerve impulses.
What are the 5 main parts of a brain?
Cerebral cortex, cerebellum, corpus callosum, hypothalamus, pituitary gland.
What does the cerebellum do?
controls body coordination, movement and balance
What does the cerebral cortex do?
It controls language, learning, intelligence and consciousness.
What does the hypothalamus do?
maintains body temperature and produces hormones for the pituitary gland. + homeostatis.
What does the pituitary gland do?
stores and releases hormones such as FSH and LH.
What does the corpus callosum do?
connects the cerebral hemispheres to allow the left and right brain to communicate.
What happens in the eye when you focus on an object far away?
The ciliary muscle relaxes, suspensory ligaments tighten/get taut, and the lens has a less rounded shape so it refracts light less.
- Paralell light rays
What happens in the eye when you focus on an object close?
Ciliary muscle contracts, suspensory ligament slackens, lens has a rounded shape to refract light more.
- Diverging light rays.
