lOMoARcPSD|4400775
Exam 1 Lecture 4
Animal Physiology (Louisiana Tech University)
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, lOMoARcPSD|4400775
Lecture 4
1. List & describe the different types of cell signaling molecules/messengers.
● Cells need to communicate with each other to coordinate responses to changes in the
internal or external environment
● Many compounds used as messengers cannot diffuse through the cell membrane or enter
through channels/transporters
● How do cells respond to these messengers?
o Message is transferred from outside to inside the cell via membrane proteins in a
process called cell signaling
● Cell signaling:
o Messengers: compounds that alter the behavior/function of cells
▪ Can be classified by how they work or the locations of their target cells
▪ Molecules on the surface of other cells (immune function and contact
inhibition)
▪ Endocrine: hormones released into the bloodstream to reach distant cell
targets
▪ Paracrine: targets nearby cells
▪ Autocrine: target is cell that produces compound
● Autocrine messengers are produced by the cell it acts on
▪ Neurotransmitter: produced by neurons, nearby target
▪ Neurohormone: produced by neurons and released into bloodstream to
reach distant target
▪ Pheromone: produced by cells of one organism with targets in another
organism
2. What are the steps involved in cell signaling? Why is cell signaling necessary?
● Signal reception
o Message needs to be detected by target cell
● Signal transduction
o Process of transferring message from outside to inside the cell and altering
cellular activity
o Generally, involves amplification (multiple product molecules produced)
● Effect
o Change in cell metabolism
o Enzymes turned on/off
o Change in electrical charge of cell membrane (excitable cells: neurons & muscles)
o Change in gene expression
3. Describe the different types of receptors involved in cellular communication.
● Signal reception
o Receptor: molecule (or parts of molecules) found on the cell surface that receives
chemical signals from outside the cell
▪ Intracellular receptors
● Receptors can be found in nucleus or cytoplasm
1
Downloaded by Alexa Martinez ()
Exam 1 Lecture 4
Animal Physiology (Louisiana Tech University)
StuDocu is not sponsored or endorsed by any college or university
Downloaded by Alexa Martinez ()
, lOMoARcPSD|4400775
Lecture 4
1. List & describe the different types of cell signaling molecules/messengers.
● Cells need to communicate with each other to coordinate responses to changes in the
internal or external environment
● Many compounds used as messengers cannot diffuse through the cell membrane or enter
through channels/transporters
● How do cells respond to these messengers?
o Message is transferred from outside to inside the cell via membrane proteins in a
process called cell signaling
● Cell signaling:
o Messengers: compounds that alter the behavior/function of cells
▪ Can be classified by how they work or the locations of their target cells
▪ Molecules on the surface of other cells (immune function and contact
inhibition)
▪ Endocrine: hormones released into the bloodstream to reach distant cell
targets
▪ Paracrine: targets nearby cells
▪ Autocrine: target is cell that produces compound
● Autocrine messengers are produced by the cell it acts on
▪ Neurotransmitter: produced by neurons, nearby target
▪ Neurohormone: produced by neurons and released into bloodstream to
reach distant target
▪ Pheromone: produced by cells of one organism with targets in another
organism
2. What are the steps involved in cell signaling? Why is cell signaling necessary?
● Signal reception
o Message needs to be detected by target cell
● Signal transduction
o Process of transferring message from outside to inside the cell and altering
cellular activity
o Generally, involves amplification (multiple product molecules produced)
● Effect
o Change in cell metabolism
o Enzymes turned on/off
o Change in electrical charge of cell membrane (excitable cells: neurons & muscles)
o Change in gene expression
3. Describe the different types of receptors involved in cellular communication.
● Signal reception
o Receptor: molecule (or parts of molecules) found on the cell surface that receives
chemical signals from outside the cell
▪ Intracellular receptors
● Receptors can be found in nucleus or cytoplasm
1
Downloaded by Alexa Martinez ()
