2.2 Control and communication (1) Flashcards
Why do multicellular organisms need communication systems
In order to survive the human body must be able to take information from the outside world and respond to it. Organs and systems within the body must be able to share information to coordinate processes
Identify the two internal communication systems in the human body.
Nervous system
Endocrine system
Identify the three main structures that make up the nervous system of an animal
Brain
Spinal cord
Nerves
Identify the two structures that make up the central nervous system (CNS)
Central nervous system (CNS)= brain+spinal cord
What is the function of the CNS
The CNS processes information from the sense organs, sends about messages along motor neutrons to bring about a response in either a muscle or a gland (part of endocrine system)
What are the three main parts of the brain and state the function of each part
- Medulla, controls breathing and heart RATE
- Cerebrum, conscious thoughts, personality, problem solving, memories ect
- Cerebellum, co-ordination of balance
What does the spinal cord do?
Links brain and nerves
How is information transmitted along neurons?
Information is transmitted along neurons as electrical impulses
What do the sense organs contain?
The sense organs contain receptors, these receptors pick up stimuli (info) about the enviorment
What happens with the information that is picked up by the receptors
The information is then passed to the CNS. Depending on the info the body may need to respond
What are the parts of the body which bring about a response to stimuli?
The parts of the body which bring about a response are called effectors
What are effectors?
Effectors= Muscle or glands in the body
Identify the tiny gaps that separate neurones from each other
Neurons do not come into physical contact with each other. They are separated by tiny gaps called synapses
Explain stage one of the synapse diagram
- Electrical impulse arrives at the end of the neutron
Explain stage two of the synapse diagram
2.Impules cause vesicles containing neurotransmitters to fuse with the cell membrane
Explain stage three of the synapse diagram
- Neurotransmitters diffuse across the synapse
Explain stage four of the synapse diagram
- Neurotransmitters bind with receptors on the next neuron
Explain stage five of the synapse diagram
- Electrical impulse generated in the next neuron
What is a reflex action
A reflex action is an automatic response to a stimuli that happens very fast. It does not involve the brain
Describe the role of the CNS in processing and responding to information from the sense
Sensory neurons pick up a stimuli and transmit an impulse to the CNS which contains interneurons- This is where processing decides if a response is required or not.Many stimuli are detected and receive by to the CNS but not all are responded to, many are filtered out. If processing determines that a response is required, another impulse will then be sent.
Identify two types of response triggered by a motor neuron
A muscle contraction to bring about movement or secretion from a gland releasing a chemical messenger (hormone.)
Identify the sequence of neurons involved in a reflex arc
Sensory neuron - detects the stimulus
Inter neuron- Receives signal from the sensory neuron and passes it to the motor neuron
Motor neuron- Carries the signal to bring about a response
(SIM)
