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What are receptors?
Receptors are specialized structures that detect stimuli.
What are stimuli?
Stimuli are changes in the environment that can elicit a response.
What are neurons?
Neurons are the basic building blocks of the nervous system.
What are the three types of neurons?
- Sensory neurons
- Motor neurons
- Interneurons
What are synapses?
Synapses are junctions between neurons that allow for communication.
How do synapses work?
Synapses work by neurotransmitters being released from one neuron and binding to receptors on another.
What are neurotransmitters?
Neurotransmitters are chemicals that transmit signals across a synapse.
What are the parts of the brain?
- Cerebrum
- Cerebellum
- Brainstem
What are hormones?
Hormones are chemical messengers produced by glands.
How are hormones different from neurotransmitters?
Hormones travel through the bloodstream, while neurotransmitters act locally at synapses.
What are the functions of hormones?
- Regulate metabolism
- Control growth and development
- Influence mood
What are the main glands in the body?
- Pituitary gland
- Thyroid gland
- Adrenal glands
How do hormones send messages?
Hormones send messages by binding to specific receptors on target cells.
What is the negative feedback system?
A mechanism that maintains homeostasis by reversing a change.
What is the stimulus-response model?
A model that describes how stimuli lead to responses.
What is reflex action?
A quick, automatic response to a stimulus.
Fill in the blank: The three types of neurons are sensory neurons, motor neurons, and _______.
interneurons
True or False: Hormones act immediately and locally like neurotransmitters.
False
What is the function of sensory receptors?
To detect stimuli from the environment.
Name four types of sensory receptors and the stimuli they detect.
- Photoreceptors - light
- Mechanoreceptors - pressure and sound
- Thermoreceptors - temperature
- Chemoreceptors - chemicals
Describe the roles of the following parts of a neurone: axon.
Transmits electrical impulses away from the cell body.
Describe the roles of the following parts of a neurone: dendrite.
Receives signals from other neurones.
Describe the roles of the following parts of a neurone: nucleus.
Contains the genetic material and controls cell activities.
Describe the roles of the following parts of a neurone: myelin sheath.
Insulates the axon to speed up electrical impulses.
Describe the roles of the following parts of a neurone: axon terminal.
Releases neurotransmitters into the synapse.
Describe the roles of the following parts of a neurone: cell body.
Contains the nucleus and organelles; integrates signals.
Explain how the nervous system sends messages.
Messages travel along axons as electrical impulses and are transmitted across synapses using neurotransmitters.
Describe the impact the deterioration of the myelin sheath has on the disease MS.
Leads to slower transmission of impulses and potential loss of function.
Using a diagram, explain how signals are transferred between neurones.
Includes terms: synapse, neurotransmitter, pre-synaptic axon terminal, receptor, post-synaptic dendrite, electrical impulse, vesicle, chemical signal.
Contrast the role of sensory, motor and interconnecting neurones.
- Sensory neurones - carry messages to the CNS
- Motor neurones - carry messages from the CNS to effectors
- Interconnecting neurones - connect sensory and motor neurones within the CNS
Define the terms stimulus, receptor, effector and response.
- Stimulus - change in the environment
- Receptor - detects the stimulus
- Effector - carries out the response
- Response - reaction to the stimulus
Construct a stimulus-response model for: decrease in body temperature resulting in shivering.
Stimulus: Decrease in body temperature; Receptor: Thermoreceptors; Effector: Muscles; Response: Shivering to generate heat.
Construct a stimulus-response model for: catching a ball.
Stimulus: Ball approaching; Receptor: Vision; Effector: Arm muscles; Response: Reaching out to catch the ball.
Discuss the importance of reflexes.
Reflexes allow for immediate responses that protect the body without needing to send signals to the brain.
Why is a message travelling to the spinal cord more beneficial than travelling to the brain?
It allows for faster reactions to stimuli, reducing potential harm.
Name the parts that make up the CNS and PNS.
- CNS: Brain, spinal cord
- PNS: Nerves outside the CNS
Identify the difference between the CNS and PNS.
CNS processes information; PNS transmits signals between the CNS and the rest of the body.
Describe the function of the frontal lobe.
Involved in decision-making, problem-solving, and controlling behavior.
Describe the function of the temporal lobe.
Involved in processing auditory information and memory.
Describe the function of the occipital lobe.
Responsible for visual processing.
Describe the function of the parietal lobe.
Processes sensory information related to touch, temperature, and pain.
Name the major endocrine glands.
- Pituitary gland
- Thyroid gland
- Adrenal glands
- Pancreas
- Gonads (ovaries/testes)
What hormones do the major endocrine glands release?
- Pituitary gland - growth hormone
- Thyroid gland - thyroxine
- Adrenal glands - adrenaline
- Pancreas - insulin, glucagon
- Gonads - estrogen, testosterone
Explain how hormones work in the body.
Hormones are released into the bloodstream and affect target cells by binding to their receptors.
Complete the following table comparing the Nervous and Endocrine Systems: Speed of the message.
- Nervous System: Fast
- Endocrine System: Slow
Complete the following table comparing the Nervous and Endocrine Systems: Speed of Response to stimuli.
- Nervous System: Immediate
- Endocrine System: Gradual
Complete the following table comparing the Nervous and Endocrine Systems: Duration of response.
- Nervous System: Short-term
- Endocrine System: Long-term
Complete the following table comparing the Nervous and Endocrine Systems: Type of message.
- Nervous System: Electrical impulses
- Endocrine System: Chemical signals
Discuss the role of the hypothalamus in the endocrine system.
Regulates hormones and maintains homeostasis through the pituitary gland.
Discuss the role of the pituitary gland in the endocrine system.
Secretes hormones that control other endocrine glands.
Define the term homeostasis.
The maintenance of a stable internal environment despite external changes.
Define the term negative feedback loop.
A process that counteracts a change to maintain homeostasis.
Provide an example of where negative feedback is used to maintain homeostasis.
Regulation of body temperature.
Explain thermoregulation using a negative feedback model.
When body temperature rises, mechanisms such as sweating are activated; when it falls, shivering occurs.
Explain the control of blood glucose using a negative feedback model.
Stimulus: High glucose levels; Insulin released; Stimulus: Low glucose levels; Glucagon released.
Explain water regulation using a negative feedback model.
High blood volume triggers diuresis; low blood volume triggers retention of water.
negative feedback loop for glucose
negative feedback loop for water level
negative feedback loop for temperature
