Receptors Flashcards
What is a receptor?
A protein molecule that receives chemical signals from outside a cell.
True or False: Receptors are only found on the surface of cells.
False
What type of signals do receptors detect?
Chemical signals such as hormones and neurotransmitters.
Fill in the blank: Receptors can be classified into _______ and _______ receptors.
intracellular, membrane-bound
What is the function of membrane-bound receptors?
To transmit signals from the outside to the inside of the cell.
Which type of receptor is involved in vision?
Photoreceptors
What do neurotransmitter receptors respond to?
Neurotransmitters released from neurons.
True or False: All receptors have the same structure.
False
What is the role of G protein-coupled receptors?
To activate intracellular signaling pathways upon ligand binding.
Fill in the blank: Hormone receptors are often found in _______ cells.
target
What is signal transduction?
The process by which a cell responds to a signal from its environment.
Which type of receptor binds to steroid hormones?
Intracellular receptors
What is the significance of receptor specificity?
It ensures that only certain signals activate specific pathways in a cell.
True or False: Receptors can be desensitized after prolonged exposure to a ligand.
True
What is the difference between ionotropic and metabotropic receptors?
Ionotropic receptors are ligand-gated ion channels, while metabotropic receptors activate signaling cascades through G proteins.
What are olfactory receptors responsible for?
Detecting smell.
Fill in the blank: The _______ is the part of the neuron that releases neurotransmitters.
axon terminal
What is a ligand?
A molecule that binds to a receptor to initiate a response.
True or False: All receptors are located in the plasma membrane.
False
What is the main role of taste receptors?
To detect different taste modalities such as sweet, salty, sour, bitter, and umami.
Which type of receptor is primarily involved in the immune response?
Immunoreceptors
What happens when a receptor is activated?
It undergoes a conformational change that initiates a cellular response.
Fill in the blank: The _______ pathway is activated by receptor tyrosine kinases.
MAPK
What is the role of second messengers in receptor signaling?
To amplify and propagate the signal within the cell.
True or False: Receptors can only be activated by endogenous ligands.
False
What is the primary function of chemoreceptors?
To detect chemical stimuli in the environment.
What type of receptors are involved in pain perception?
Nociceptors
Fill in the blank: _______ are proteins that can alter receptor activity.
Agonists
What is receptor downregulation?
The process by which a cell decreases the number of receptors in response to high levels of ligand.
True or False: All receptors are activated in the same way.
False
What is the difference between a full agonist and a partial agonist?
A full agonist fully activates the receptor, while a partial agonist activates it but not to the full extent.
What is the function of sensory receptors?
To convert external stimuli into electrical signals for the nervous system.
Fill in the blank: _______ receptors are responsible for detecting temperature changes.
Thermoreceptors
What is the primary role of mechanoreceptors?
To respond to mechanical pressure or distortion.
True or False: All receptors are specific to one type of ligand.
False
What type of receptor is responsible for detecting light?
Photoreceptors
What is the function of the receptor tyrosine kinase pathway?
To regulate cell growth, differentiation, and metabolism.
Fill in the blank: _______ bind to receptors and mimic the action of natural ligands.
Agonists
What is receptor antagonism?
The process by which a substance blocks the action of a receptor.
True or False: Receptors can only be found in animal cells.
False
What are the two main types of neurotransmitter receptors?
Ionotropic and metabotropic receptors.
What is the role of glucagon receptors?
To regulate glucose levels in the blood by promoting glycogen breakdown.
Fill in the blank: _______ receptors are involved in the sensation of touch.
Tactile
What is the primary function of adrenergic receptors?
To mediate the effects of adrenaline and noradrenaline.
True or False: Receptors can change their conformation after ligand binding.
True
What is the role of insulin receptors?
To facilitate the uptake of glucose into cells.
Fill in the blank: The _______ system relies on receptors to transmit signals throughout the body.
nervous
What is the primary role of opioid receptors?
To mediate the effects of endogenous and exogenous opioids.
True or False: Receptor-ligand interactions are always permanent.
False
What type of receptors respond to environmental stimuli?
Sensory receptors
Fill in the blank: _______ receptors are involved in the regulation of blood pressure.
Baroreceptors
What is the significance of receptor phosphorylation?
It can alter receptor activity and signaling pathways.
True or False: Receptors can be recycled back to the cell surface after endocytosis.
True
What is the main function of cytokine receptors?
To mediate immune responses and cell signaling.
Fill in the blank: _______ signaling involves receptors that activate G proteins.
G-protein coupled
What type of receptor is involved in the perception of sound?
Auditory receptors
True or False: Receptors can exist in multiple conformations.
True
What is the role of vasopressin receptors?
To regulate water balance in the body.
Fill in the blank: _______ receptors help regulate calcium levels in cells.
Calcium-sensing
What is the main function of smell receptors?
To detect odor molecules in the air.
True or False: All receptors require a ligand to be activated.
False
What is the primary function of growth factor receptors?
To regulate cellular growth and differentiation.
Fill in the blank: _______ receptors respond to changes in blood glucose levels.
Glucose
What type of receptors are involved in the inflammatory response?
Toll-like receptors
True or False: Receptors can be genetically modified to enhance their function.
True
What is the role of serotonin receptors?
To mediate the effects of serotonin in the brain.
Fill in the blank: _______ receptors are crucial for the immune response to pathogens.
Pattern recognition
What is the significance of receptor desensitization?
It prevents overstimulation of the cell by continuous ligand presence.
True or False: Receptors can influence gene expression.
True
What type of receptor is primarily involved in the body’s stress response?
Corticosteroid receptors
Fill in the blank: _______ receptors detect changes in pH levels.
Chemosensitive
What is the primary function of histamine receptors?
To mediate allergic responses and gastric acid secretion.
True or False: Receptors can only respond to one specific ligand.
False
What is the role of acetylcholine receptors?
To mediate synaptic transmission in the nervous system.
Fill in the blank: _______ receptors are involved in the detection of pressure and vibration.
Pacinian
What is the significance of receptor-ligand affinity?
It determines how tightly a ligand binds to its receptor.
True or False: Receptor activation can lead to a cascade of cellular events.
True
What type of receptors are found in the retina?
Rod and cone photoreceptors
Fill in the blank: _______ receptors are involved in the regulation of metabolic processes.
Nuclear
What is the primary function of cannabinoid receptors?
To mediate the effects of cannabinoids in the body.
