Enter your Sign-on user name and password.

Forgot password?
  • Follow us on:
Loading video...

Start Learning Now

Our free lessons will get you started (Flash® 10 required).
Get immediate access to our entire library.

Sign up for Educator.com

Features Overview

  • Get on-demand access to our complete library
  • Search and jump to exactly what you need to learn
  • Track your progress
  • Download practice and lesson files
  • *Ask questions and get answers from our community & instructors

Cellular Communication

  • In plants, channels called plasmodesmata provide a means for communication between cells by allowing the cytoplasm of adjacent cells to be in contact with one another.
  • Cell junctions are connections between cells which allow for communication between cells and coordination of activities. Three types of cell junctions are desmosomes, tight junctions and gap junctions.
  • The first phase of cell signaling is the reception phase. This involves the binding of a ligand to a receptor. This interaction induces a conformational change in the receptor.
  • Three types of cell membrane receptors are G-protein coupled receptors, ligand gated ion channels and receptors with intrinsic enzyme activity, such as receptor tyrosine kinases.
  • Signal transduction is the transmission of the message from the surface of the cell to the inside of the cell via a cascade of steps, which involve the activation of enzymes and proteins.
  • Second messengers such as cAMP, cGMP, IP3 and DAG often mediate the signal transduction pathway.
  • The binding of a signal molecule to a receptor elicits a response by the cell. Responses include increasing or decreasing the transcription of a gene or increasing or decreasing the activity of a protein.

Cellular Communication

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

AP Biology Intro