cell adhesion

transport proteins!

A mnemonic for remembering the types of transport proteins:
Can I Carry The Ruddy Red Apple?

  • Can: Channel Proteins
    • open passageways for certain hydrophilic substances (polar/charged molecules)
    • example: aquaporins are a passage for water
  • I: Ion Channels
    • passage for ions
    • example: gated channels (nerve/muscle cells) open to specific chemical/electrical signals
  • Carry: Carrier Proteins
    • bind to specific molecules that are transferred across when protein changes shape
    • example: glucose enters cells by carrier proteins
  • The: Transport Proteins
    • use energy (ATP) to actively transport materials across membrane
    • example: sodium potassium pumps use ATP to maintain Na+/K+ concentrations outside/inside cell
  • Ruddy: Recognition Proteins
    • gives cells unique identification, recognize self and foreign cells
    • actually glycoproteins, proteins with short polysaccharide chains
    • example: different blood types have cells with different recognition proteins
  • Red: Receptor Proteins
    • binding sites for hormones/other triggering molecules
    • specific cell response activated
  • Apple: Adhesion Proteins
    • attach cells to neighboring cells 
    • provide anchors for internal filaments/tubules

List of proteins from (Cliffsnotes AP Biology Workbook 4th Edition)
Mnemonic credits to Caitlin ^-^

Trichomonas vaginalis is a protozoan parasite of the urogenital tract in men and women and causes a sexually transmitted disease, trichomoniasis, in about half of infected women. Infections are associated with pelvic inflammatory disease, adverse pregnancy outcomes, infertility, an increased incidence of aggressive prostate cancers, and an increase in HIV-1 transmission.

Image: Scanning electron micrograph of Trichomonas vaginalis (yellow-green) with epithelial cells (pink) where adhesion of the parasites to host cells is seen.

Illustration of the feeding mechanism of the sea gooseberry. When relaxed its tentacles expand, acting like a spider’s web to capture prey. Instead of stinging cells, these tentacles are lined with special adhesive cells to prevent prey from escaping. 

They had these little guys at the Monterey Bay Aquarium for a while, and I was absolutely fascinated by how much their tentacles can stretch. Really cool!