Coordination and Response Flashcards
Receptors
Cells which senses stimuli
Coordination
The method where receptors pick up stimuli and passes information to the effectors
Two ways of sending information from receptors to effectors
- Nerves
- Hormones
Neurons
Contains the same basic parts of a cell (Cytoplasm, nucleus and cell membrane). They are present in long chains, in order to pass messages quickly throughout the body.
Dendrones/Dentrities
The shortest fibre from the thin fibers stretching out of the neuron cell.
Mylein
A layer of fat and protein which wraps the nerve fibers of active animals
Function of mylein
Mylein insulates the nerve fibres, so that they can carry the electrical impulses faster.
Central Nervous system
Consists of the brain and spinal cord, and is made up of neurons, its role is to coordinate the messages travelling through the nervous system. When stimuli detected, sendory neuron sends electrical impulses to brain or spinal cord, which sends impulses to the appropriate effector.
Reflex arc and how it works
When your hand touches a hot plate, the sensory receptor sends a impulse to your signal cord or brain through the sensory neurons along the axon. In the sensory neuron, the impulse is passed to relay neurons because they relay the impulses on to other neurons, this impulse is passed to the brain which again send a impulse through the axon of a motor neuron to trigger muscle cells to contract.
Voluntary and involuntary action
Voluntary action: when an action is produced with the involvement of thoughts, they are called voluntary action. Involuntary actions: actions which take place without consciousness or willingness of an individual are called involuntary actions.
Synapses
a junction between two nerve cells, consisting of a minute gap across which impulses pass by diffusion of a neurotransmitter.
Synaptic clefts
The small gap between the place where neuron meet.
The path taken by impulses
Vesicles in the axon of a neuron, contain transmitter senders, which are bubbled inside the vacoule, which then empties the content into the synaptic cleft. The neurotransmitter diffuses across the tiny gap and attaches to receptor molecules in the cell membrane of the relay neurone. The triggered relay neuron send impulses until the next synapses.
Sense organs
Groups of receptor cells responding to specific stimuli
Structure of the eye
Each eye is in a bony socket of the skull called orbit, The front of the eye is covered in a thin transparent layer called conjunctiva, which is kept mosit by a fluid made in tear glands and contains lysozyme which kills bacteria.
