control and regulation revision Flashcards
What is the function of sensory receptors?
To detect stimuli from the environment and convert them into electrical signals for the nervous system
Sensory receptors include photoreceptors, mechanoreceptors, thermoreceptors, and chemoreceptors.
Name four types of sensory receptors and the stimuli they detect.
- Photoreceptors - light
- Mechanoreceptors - pressure and sound
- Thermoreceptors - temperature
- Chemoreceptors - chemicals
These receptors are essential for processing sensory information.
Describe the roles of the following parts of a neuron: axon, dendrite, nucleus, myelin sheath, axon terminal, and cell body.
- Axon - transmits electrical impulses away from the cell body
- Dendrite - receives signals from other neurons
- Nucleus - contains genetic material
- Myelin sheath - insulates the axon to increase signal speed
- Axon terminal - releases neurotransmitters to communicate with other neurons
- Cell body - contains the nucleus and organelles
Each part plays a crucial role in neuron function and communication.
What direction does a message travel in the nervous system?
From sensory receptors to the central nervous system (CNS) and then to effectors
Messages travel in a specific pathway: sensory neurons → interneurons → motor neurons.
What is the impact of the deterioration of the myelin sheath in multiple sclerosis (MS)?
It disrupts the transmission of electrical impulses, leading to symptoms like weakness, numbness, and coordination issues
MS is an autoimmune condition affecting the nervous system.
Explain how signals are transferred between neurons.
Signals are transferred across a synapse using chemical signals (neurotransmitters) released from the pre-synaptic axon terminal to bind with receptors on the post-synaptic axon terminal
The process involves electrical impulses triggering vesicles to release neurotransmitters.
Contrast the roles of sensory, motor, and interconnecting neurons.
- Sensory neurons - carry messages from receptors to the CNS
- Motor neurons - carry messages from the CNS to effectors
- Interconnecting neurons - connect sensory and motor neurons in the CNS
Each type of neuron has a distinct function in processing and responding to stimuli.
Define the terms: stimulus, receptor, effector, and response.
- Stimulus - a change in the environment
- Receptor - detects the stimulus
- Effector - responds to the stimulus
- Response - the action taken as a result
These terms are fundamental to understanding how organisms interact with their environment.
Contrast a stimulus-response model for a) Decrease in body temperature resulting in shivering.
Stimulus: decrease in body temperature; Receptor: thermoreceptors; Effector: muscles; Response: shivering
This is an example of a physiological response to maintain homeostasis.
Contrast a stimulus-response model for b) catching a ball.
Stimulus: ball approaching; Receptor: visual receptors; Effector: arm muscles; Response: catching the ball
This response involves rapid processing and motor coordination.
Discuss the importance of reflexes.
Reflexes provide a quick response to stimuli, allowing for immediate action without involving the brain, which is beneficial for survival
This rapid response minimizes potential harm.
Draw a reflex arc to show someone touching a hot iron.
Reflex arc includes: sensory neuron, spinal cord (interneuron), motor neuron, effector (muscle)
This illustrates the pathway of a reflex action.
Name the parts that make up the CNS and PNS.
CNS: brain, spinal cord; PNS: nerves outside the CNS
The CNS processes information, while the PNS connects the CNS to the rest of the body.
Describe the function and location of the frontal lobe.
Function: reasoning, planning, problem-solving; Location: front part of the brain
The frontal lobe is crucial for higher cognitive functions.
Describe the function and location of the temporal lobe.
Function: processing auditory information, memory; Location: side of the brain
The temporal lobe is involved in understanding language and storing memories.
Describe the function and location of the occipital lobe.
Function: visual processing; Location: back part of the brain
The occipital lobe is essential for interpreting visual stimuli.
Describe the function and location of the parietal lobe.
Function: sensory perception and integration; Location: top part of the brain
The parietal lobe processes tactile information.
Name the major endocrine glands.
- Pituitary gland
- Thyroid gland
- Adrenal glands
- Pancreas
- Gonads
Each gland releases specific hormones that regulate various bodily functions.
Explain how hormones work in the body.
Hormones are released into the bloodstream and bind to target cells with specific receptors to elicit a response
This process regulates numerous physiological functions.
Compare the nervous and endocrine system.
- Nervous system - fast, short-term responses via electrical impulses
- Endocrine system - slower, long-term responses via hormones
Both systems are crucial for maintaining homeostasis.
Discuss the role of the hypothalamus in the endocrine system.
The hypothalamus regulates hormonal secretions from the pituitary gland and maintains homeostasis
It links the nervous system to the endocrine system.
Discuss the role of the pituitary gland in the endocrine system.
The pituitary gland secretes hormones that regulate various bodily functions and control other endocrine glands
Often referred to as the ‘master gland’.
Define the term homeostasis.
The maintenance of a stable internal environment despite external changes
Homeostasis is vital for the proper functioning of organisms.
Define the term negative feedback loop.
A process that counteracts a change to maintain homeostasis
An example is the regulation of body temperature.
Explain thermoregulation using a negative feedback model.
When body temperature rises, mechanisms like sweating are activated; when it drops, shivering occurs
Both the nervous and endocrine systems are involved in this process.
Explain the control of blood glucose using a negative feedback model.
When blood glucose levels rise, insulin is released to lower it; when levels fall, glucagon is released to raise it
This regulation is essential for energy balance.
Explain water regulation using a negative feedback model.
When blood volume is high, the body increases urine production; when low, it conserves water
This regulation maintains fluid balance.
