Textbook Notes (368,460)
United States (206,052)
Biology (392)
CAS BI 108 (112)
Chapter 7

Chapter 7.docx

2 Pages
Unlock Document

CAS BI 108
Francis Monette

Savan Shah CH 110 Outline Chapter 7 Chapter 7: Cell Communication and Multicellularity I. WhatAre Signals, and How Do Cells Respond to Them? -Signal Transduction Pathway  Sequence of molecular events and chemical reactions that lead to a cell’s response to a signal (Signal, Receptor, Response) • Autocrine  Diffuse to and affect cells that make them (ex: tumor cells reproduce uncontrollably because they make and respond to signals that stimulate cell division) • Juxtacrine  Affects only cells adjacent to cell producing the signal • Paracrine  Diffuse to and affect nearby cells (ex: Neurotransmitter made by one nerve cell that diffuse to nearby cell and stimulates it) • Hormones  Signals that travel through the circulatory systems of animals or vascular systems of plants • Only cells with appropriate receptors can respond oEither activated or inactivated to bring about cellular changes oActivity of protein can be regulated by mechanisms that control its location in cell oCrosstalk  Interactions between different signal transduction pathways  Signal transduction pathways often branch  Single activated protein might activate enzymes or transcription factors in multiple pathways  Multiple signal transduction pathways might converge on single transcription factor  Can result in activation of one pathway and inhibition of another II. How Do Signal Receptors Initiate Cellular Response? -Receptor protein recognizes its signal very specifically  Specificity ensures that only those cells that make specific receptor will respond to given signal • Ligand  Molecule that binds to receptor site on another molecule (initiates cellular response) • Sensitivity of cell to signal is determined in part by affinity of cell’s receptors for signal ligand • Binding is reversible  If ligand were never released, the receptor would be continuously stimulated • Dissociation Constant (K D  The lower the K ,Dthe higher the binding ability of ligand for the receptor; Higher the K D need more ligand to set off their signal transduction pathways
More Less

Related notes for CAS BI 108

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.