Intercellular commication and signal transduction
1 / 18

Intercellular Commication and Signal Transduction - PowerPoint PPT Presentation

  • Uploaded on

Intercellular Commication and Signal Transduction. Chapter 4. Intercellular Communication. Cells of body must communicate with one another Coordinates organ systems Takes place directly: Physical contact between cells Gap junctions Direct linkage of surface markers Or indirectly

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Intercellular Commication and Signal Transduction' - lester

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

Intercellular communication
Intercellular Communication

  • Cells of body must communicate with one another

  • Coordinates organ systems

  • Takes place directly:

    • Physical contact between cells

      • Gap junctions

      • Direct linkage of surface markers

  • Or indirectly

    • Extracellular chemical messengers or signal molecules

    • Specific to target cell receptors

Chemical messengers
Chemical Messengers

  • Four types of chemical messengers

    • Paracrines

      • Local chemical messengers

      • Exert effect only on neighboring cells in immediate environment of secretion site

    • Neurotransmitters

      • Short-range chemical messengers

      • Diffuse across narrow space to act locally on adjoining target cell (another neuron, a muscle, or a gland)

Chemical messengers1
Chemical Messengers

  • Hormones

    • Long-range messengers

    • Secreted into blood by endocrine glands in response to appropriate signal

    • Exert effect on target cells some distance away from release site

  • Neurohormones

    • Hormones released into blood by neurosecretory neurons

    • Distributed through blood to distant target cells

Chemical messengers2
Chemical Messengers

  • Cell responses brought about primarily by signal transduction

    • Incoming signals conveyed to target cell’s interior

  • Binding of extracellular messenger (first messenger) to receptor brings about intracellular response by either

    • Opening or closing channels

      • Chemically gated receptor channel

    • Activating second-messenger systems

      • Activated by first messenger

        • Receptor-enzyme

      • Relays message to intracellular proteins that carry out dictated response

        • G-protein coupled receptor

Intercellular commication and signal transduction


Tyrosine kinase pathway


  • Endocrinology

    • Study of homeostatic activities accomplished by hormones

  • Two distinct groups of hormones based on their solubility properties

    • Hydrophilic hormones

      • Highly water soluble

      • Low lipid solubility

    • Lipophilic hormones

      • High lipid solubility

      • Poorly soluble in water

Class questions
Class Questions messenger pathway

  • There are 3 ways cells communicate. The 2 direct means of communication is through ___________ and _______________. Cells indirectly communicate through _______________.

  • Name and describe the 4 types of chemical messengers. Include which fluid medium they travel through: blood, extracellular fluid, intracellular fluid.

  • Why is a neurotransmitter different than paracrine signalling?

  • What is a syncytium?

  • What is a ligand? What is a receptor?

  • How does a chemical messenger “know” which organ to affect?

  • Name 3 ways that an extracellular chemical messenger can bring about an intracellular response.

  • Is the response between a chemical messenger and a particular receptor always the same?

  • How can a chemical receptor elicit a different response inside a cell?

  • In a second messenger system, where does the first messenger bind? Where is the second messenger?

Class questions1
Class Questions messenger pathway

  • There are 2 major 2nd messengers: cyclic AMP and Ca2+ . Describe the action of a hydrophilic hormone via activation of the cyclic AMP 2nd messenger pathway. If you draw pictures, you must label everything and explain what is happening.

  • How does using an 2nd messenger system amplify the response inside the cell?

  • How do some chemical messengers affect gene activity (hence, protein synthesis) within a cell?

  • Which type of hormone can affect gene activity, hydrophilic or lipophilic? Why?