Chapter 14 - response to stimuli Flashcards
What is the definition of a stimulus?
A stimulus is any change in the environment that can provoke a response from an organism.
What is the role of receptors in response to stimuli?
Receptors detect stimuli and convert them into electrical impulses.
True or False: Effectors are organs that bring about a response.
True
Fill in the blank: The nervous system is responsible for _____ responses.
rapid
What are the two main types of responses to stimuli?
Nervous response and hormonal response.
What is the function of a synapse?
A synapse is the junction between two neurons where neurotransmitters are released to transmit signals.
What is a reflex action?
A reflex action is an involuntary and rapid response to a stimulus.
Identify the pathway of a reflex arc.
Stimulus → Receptor → Sensory neuron → Relay neuron → Motor neuron → Effector.
What is the difference between a voluntary and involuntary response?
Voluntary responses are consciously controlled, while involuntary responses occur automatically without conscious thought.
Name the type of neuron that carries impulses from receptors to the central nervous system.
Sensory neuron.
What is the role of the central nervous system?
The central nervous system processes information and coordinates responses.
True or False: Hormonal responses are usually slower than nervous responses.
True
What type of cells are involved in the response to stimuli in plants?
Plant cells with receptors, such as auxins.
Fill in the blank: The _____ is responsible for processing sensory information.
brain
What is the function of neurotransmitters?
Neurotransmitters transmit signals across synapses between neurons.
What is the role of the motor neuron in a reflex action?
The motor neuron carries the impulse from the relay neuron to the effector.
What is an example of a plant response to stimuli?
Phototropism, where plants grow towards light.
How do hormones affect responses in the body?
Hormones act as chemical messengers that regulate physiological processes and responses.
What is the role of the spinal cord in reflex actions?
The spinal cord facilitates the reflex action by connecting sensory and motor neurons.
True or False: All stimuli result in a response.
False
What is the term for the process by which organisms detect and respond to their environment?
Sensory processing.
What is meant by ‘threshold level’ in response to stimuli?
Threshold level is the minimum stimulus intensity required to trigger a response.
What is the function of the endocrine system in response to stimuli?
The endocrine system releases hormones that regulate long-term changes in response to stimuli.
What is the primary type of response mediated by the autonomic nervous system?
Involuntary responses.
Fill in the blank: The _____ is involved in voluntary movement and coordination.
cerebellum
What is the role of the hypothalamus in response to stimuli?
The hypothalamus regulates homeostasis and coordinates responses to internal stimuli.
What do we call the change in behavior or physiology in response to a stimulus?
Response.
What is the term for the gradual decrease in response to a constant stimulus?
Habituation.
True or False: The peripheral nervous system includes the brain and spinal cord.
False
Name one example of a stimulus that can trigger a hormonal response.
Stress.
What is the function of the somatic nervous system?
The somatic nervous system controls voluntary movements of skeletal muscles.
What type of receptor responds to changes in light?
Photoreceptors.
Fill in the blank: The _____ system regulates fight or flight responses.
sympathetic
What is the role of the parasympathetic nervous system?
The parasympathetic nervous system promotes ‘rest and digest’ functions.
What is the significance of the ‘all-or-nothing’ response in neurons?
It means that a neuron either fires fully or not at all, depending on whether the threshold is reached.
What is an example of a voluntary response?
Deciding to move your hand away from a hot surface.
What kind of stimuli can affect plant growth?
Light, gravity, and water.
True or False: Receptors can be specific to certain types of stimuli.
True
How do sensory neurons transmit information to the brain?
They send electrical impulses through the nervous system.
What is the purpose of a reflex test?
To assess the integrity of the nervous system and the reflex arc.
