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Communication+Homeo
questions on communication and homeostasis and the nervous system
Question | Answer |
---|---|
What is a stimulus? | A change in the internal or external environement |
What is a receptor? | Detects stimuli. They are specfic and can can only detetct a particular stimulus |
What is an effector | Effectors bring about a response to the stimulus to produce an effect eg. muscle or gland |
What is cell signalling? | Communication between distant or adjacent cells. In nerves, cells communicate by a chemical called neurotransmitters which send signals to other cells. |
What is the purpose of cell surface receptors? | They allow cells to recognise chemicals involved in cell signalling |
Why is it important that organisms respond to stimuli? | To increase their chances at survival |
Give one reason why communication systems are needed in multicelluar organisms. | To ensure that the organisms activities are coordinated and working effectively |
What is a sensory neurone? | Transmits nerve impulses from receptors to the CNS |
What is a motor neurone? | Transmits nerve impulses from CNS to effectors |
What is a relay neurone? | Transmit nerve impulses between sensory neurones and motor neurones |
What are dendrites and dendrons? | They carry nerve impulses toward the cell body |
What is the structure of a sensory neurone? | Short dendrites and one long dendron that carries nerve impulses from receptor cells to the cell body. They also have one axon that carries nerve impulses from cell body to CNS |
What is the structure of a motor neurone? | Many short dendrites that carry nerve impulses from CNS to cell bod, one long axon that carries nerve impulses from cell body to effector |
What is the structure of a relay neurone? | Many short dendrites that carry nerve impulses from sensory neurones to the cell body and many short axons that carry nerve impulses from the cell body to motor neurones |
What is the order of evenst that takes place when a stimulus is detected? | Stimulus - Receptor - Sensory Neurone to CNs - Motor Neurone to effector - Response |
What is a transducer? | Converts one form of energy into another. Sensory receptors convert the energy of a stimulus into electrical energy |