1 / 18

Cell Communication

Cell Communication. Ch. 6, 7, and 11. Direct Contact. Plants plasmodesmata connect cytoplasm. Figure 6.31. Cell walls. Interior of cell. Interior of cell. Plasma membranes. Plasmodesmata. 0.5 m. Direct Contact. Bacteria quorum sensing coordinate behaviors to produce a biofilm. 1.

easter
Download Presentation

Cell Communication

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. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. CellCommunication Ch. 6, 7, and 11

  2. Direct Contact • Plants plasmodesmata connect cytoplasm

  3. Figure 6.31 Cell walls Interiorof cell Interiorof cell Plasma membranes Plasmodesmata 0.5 m

  4. Direct Contact • Bacteria quorum sensing coordinate behaviors to produce a biofilm

  5. 1 2 3 Figure 11.3 Individualrod-shapedcells Aggregation in progress 0.5 mm Spore-formingstructure(fruiting body) 2.5 mm Fruiting bodies

  6. Direct Contact • Animals have nonmotile cilia that function like a receiving antenna • Most vertebrate cells have one per cell • Crucial for brain function and embryonic development

  7. Animal cell junctions • Tight junctions-prevent leakage of extracellular fluid (skin cells are watertight) • Anchoring junctions (desmosomes)- act like rivets to anchor cell to cell (form strong sheets of cells, bind muscle cells together) • Gap junctions- like plasmodesmata in plants; these are communicating junctions necessary for communication especially in heart muscle and embryoes

  8. Plasma membranes Figure 11.4 Gap junctionsbetween animal cells Plasmodesmatabetween plant cells (a) Cell junctions (b) Cell-cell recognition

  9. Tight junctions preventfluid from movingacross a layer of cells Figure 6.32 Tight junction TEM 0.5 m Tight junction Intermediatefilaments Desmosome TEM 1 m Gapjunction Ions or smallmolecules Spacebetween cells TEM Extracellularmatrix Plasma membranesof adjacent cells 0.1 m

  10. Membrane Structure • Membrane carbohydrates allow for cell to cell recognition • Usually are glycoproteins but may be lipoproteins

  11. Local Regulators • Influence cells in vicinity • In animals growth factors stimulate nearby cells to grow and divide • Paracrine signaling- local regulator diffuses through extracellular fluid • Synaptic signaling- neurotransmitters

  12. Figure 11.5a Local signaling Electrical signalalong nerve celltriggers release ofneurotransmitter. Target cell Neurotransmitter diffuses across synapse. Secretingcell Secretoryvesicle Local regulatordiffuses throughextracellular fluid. Target cellis stimulated. (b) Synaptic signaling (a) Paracrine signaling

  13. Long Distance Signaling • Hormones using signal transduction pathways

  14. Long-distance signaling Figure 11.5b Endocrine cell Bloodvessel Hormone travelsin bloodstream. Target cellspecificallybinds hormone. (c) Endocrine (hormonal) signaling

  15. Cell Signaling • Leads to regulation of transcription factors or cytoplasmic factors • All cell communication relies on specific receptor molecules for binding

  16. Growth factor Reception Receptor Figure 11.15 Phosphorylationcascade Transduction CYTOPLASM Inactivetranscriptionfactor Activetranscriptionfactor Response P DNA Gene NUCLEUS mRNA

  17. Apoptosis • Programmed cell death is a means of cell communication • When this mechanism is activated or deactivated will determine body structures

  18. Figure 11.22 Cells undergoingapoptosis Space betweendigits 1 mm Interdigital tissue

More Related