B6 Flashcards
What is a reflex?
A reflex is an automatic response to a stimulus. Reflex actions have a fixed pathway of neurons that allows the very rapid response to take place as their isn’t any processing of the information by the brain.
What do humans use reflex actions for? Give an example.
Humans use reflex actions in only some of their behaviour, for example controlling the eye’s pupil size.
How does a stimulus lead to a response?
Stimulus Receptor Sensory neurons Relay neurons (spinal cord) Motor neurons Effectors Response
What are the newborn reflexes?
Stepping reflex
Grasping reflex
Sucking reflex
What are human reflexes?
Pupil reflex
Knee jerk
Dropping hot objects
Blinking
What is the nervous system made up of?
Brain
Spinal cord
Neurones (nerve cells)
What are receptors, stimuli and effectors?
Receptors are groups of specialised cells. They can detect changes in the environment (stimuli) and turn them into electrical impulses. Receptors are often located in the sense organs, such as the ear, eye and skin. Effectors are parts of the body that produce a response, e.g a muscle contradiction to move an arm.
What is the central nervous system made up of?
Brain
Spinal cord
What does the peripheral nervous system consist of?
Peripheral nerves
What are the 3 main parts of the brain?
Cerebrum - largest part of the brain, controls speaking, thinking, hearing, vision and all voluntary acts
Cerebellum - controls balance + muscle coordination
Medulla - controls all involuntary acts (breathing, heart beat, digestion, reflexes)
What are nerves?
Nerves are bundles of specialised cells called neurons. Neurons carry nerve impulses. There are tiny gap between the neurons called synapses. Chemicals are released from the sensory neuron and it diffuses across the synapse.
What are the difference parts of the neuron?
Dendrites - receivers
Myelin sheath - insulation fatty layer which speeds up transmission
(Long) Axon - the conducting fiber
What is sensory memory?
Sensory memory can be used to store sound and visual information for a short time.
What was Pavlov’s experiment?
Pavlov trained his dogs to expect food whenever he rang a bell and so they started salivating.
What are Beta Blockers?
Prescription drugs that block the transmitter molecule adrenalin so they reduce the heart rate, they are used to treat people with heart rhythm problems, some people use it to control anxiety (sports etc)
