Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Do you really want to delete this prezi?
Neither you, nor the coeditors you shared it with will be able to recover it again.
Make your likes visible on Facebook?
You can change this under Settings & Account at any time.
Copy of AP Bio- Cells 5: Communication
Transcript of Copy of AP Bio- Cells 5: Communication
Two mating types (a and alpha). Each makes signaling molecules that the other recieves.
The reception of a mating factor leads to the production of a mating "Shmoo"
Fusion of shmoo's = diploid yeast cell.
Meiosis soon ensues
Yeast shmoo mutants & the shmoo formation pathway
Graphic Yeast Sex
Fruiting Body Formation in Soil Bacteria in response to poor environmental conditions
Plaque Biofilm All Up On Your Teeth!
communication among microbes that triggers group response once particular population densities are reached
A bacterium that lives inside organs in marine animals.
When population density hits a threshold, they begin to produce a light-producing protein.
This gives the host animal bioluminescence.
Model of quorum sensing in V. fischeri.
Don't worry about the specifics, focus on the big picture
Biofilms are bacterial ecosystems that are established and maintained due to elaborate quorum sensing networks
It's All About Signal Reception!
Why do cells communicate?
What does cellular communication look like?
How is cellular communication utilized in unicellular and multicellular life?
Make Sure You Can
How Cells Communicate: Signal Transduction
The 3 Phases of Signal Reception
How Signals are Recieved
The ligand isn't important.
The Response is!
Cells Amplify A Message
Things Get Complicated Quickly
An Epinephrine Receptor
What kind of hormone is epinephrine (polar or non-polar)?
Epinephrine signal transduction is mediated by G-Protein linked receptors.
It has multiple effects, but one response is the inhibition of glycogen synthesis and the acceleration of glycogen breakdown (why?)
Internal signalling molecules released due to external ("first") signals. Trigger sub-response pathways.
Programmed cell death is programed because of the signalling pathway that it is programmed to.
Epinephrine is a polar amine ligand
Why Cells Communicate: Some Examples
How Signals Are Sent
Long Distance Signals
The Nervous and endocrine systems handle these things in animals. We will talk about them in depth, later in the course
Widely conserved among all domains (why?)
G-Protein Linked Reception
Ligand-gated Ion Channels
proteins activated by the transfer of a phosphate from a molecule of GTP.
The first step in the protein relay
Kinase: A protein that "phosphorylates" (adds a phosphate) to another molecule
proteins that form dimers. Tyrosine amino acid residues are active in the transfer of phosphates to relay proteins.
Remain active as long as the ligand is attached.
The incoming ions trigger the response
Cyclic AMP: A typical second messenger that affects metabolism.
Calcium ions are another common second messenger.
A common hormone in vertebrates.
Involved in short term stress ("fight or flight") response.
More from less
What kind of feedback?
A "Branching Network"
Simplicity leads to Complexity
Pretty much any chemical or energy source could serve as a biological signal...
...though most are biologically created molecules
Note: We will only look at unicellular examples in this lesson (animals and plants later!)
How can this kind of behavior evolve?
Notice that death proteins are present in an inactive form prior to signal reception (Why?)
Explain why and how cells communicate with the environment.
Explain the common features shared among cellular communication processes.
Compare the purpose of cellular communication in unicellular and multicellular organisms
Describe the major features of signal transduction pathways in cells.
Connect cellular signaling patways to actual examples as discussed in this presentation.
Discuss the evolutionary/adaptive considerations of cellular signaling pathways.
Here's an example: