BIO_181_Test_Bank_1

BIO_181_Test_Bank_11)Pancake-shaped cells explores the environment – moving filopodia with receptors extend from cell surface all over cell and “sense” environment. (1 point) 2) Then in some area filopodia stop moving due to signal received (biochemical cascade changes cell in that area). (1 point) 3) That area restructures to extend large, lamellipodium that pushes out against the plasma membrane; the mechanism causing this is a new network of actin filaments. (1 point) 4) When lamellipodium touches substrate cell-equivalent of super glue/adhesion plaque holds substrate. (1 point) 5) Cell equivalent of a muscle (i.e. actin and myosin) assembles and attaches to adhesion plaque and extends towards nucleus. (1 point) 6) The muscle contracts pulling the back end of the cell forward. (1 point) 7) The above process repeats itself as cell walks directionally. The students must mention that the process repeats (ie you can’t tell if a person is walking if they just stick out their left leg.) (1 point)