Module 20 Flashcards
Cell commuication and cell cycle
Population
All the individuals of a given species that live and reproduce in a particular geographic area
Steps of communication
A stimulus
The release of the signal
The reception of the signal
Response
What does the signalling cell do
Receives and responds to a STIMULUS
How do signalling cells respond to stimulus
By making and releasing signalling molecules
Signalling Molecules
chemicals released by cells that alter the activity of other cells
AKA Ligands
Receptor Protiens
Proteins on a cells surface or in a cell’s interior that bind specific signalling molecules
The Target Cell
The cell that receives the signal released by a signal cell
Ligands
Signalling Molecules; chemicals released by cells that alter the activities of other cells
Ligand-receptor interaction
The signalling molecule must be specifically matched or must complement the receptor protein
What is the purpose of ligand-receptor interactions
To make sure that a signal is received ONLY by the appropriate cell
What kind of bond hold ligand-receptor interactions
Weak, noncovalent bonds
Quorum sensing
Communication among bacteria that leads to a response ONLY when there are a HIGH number of bacteria present in a given area
Why must there be high population density in order for Quorum sensing to work
It turns on a communication pathway
At low population density there is very little signal in the environment, so they are unlikely to bind to bacteria’s protein receptors
At high population density, more signal molecules are released and are able to bind to protein receptors.
Bacteria then respond by synthesizing chemicals like bioluminescence
All target cells respond the same
False, for example target cells triggered by adrenaline increases heart rate , increasing the amount of oxygen delivered throughout the body. when target cells in the lung receives the signal molecule, the lungs cells relax
Identify the four steps of cell communication in the fight or flight
Stimulus: being startled
Signalling Cells produce signalling molecules: adrenal glands and adrenaline
Molecule binds to receptor: Receptor proteins on the heart and lungs
Response: increased heart rate and relaxed lung cells
What determines what a target cell is
The corresponding receptor protien
Hormone
A type of signaling molecule that travels in the CIRCULATORY system and effects DISTANT cells