BI110 Chapter Notes - Chapter 15: Kinesin, Basal Body, Treadmilling
Document Summary
Co(cid:374)tai(cid:374)s protei(cid:374)s that (cid:373)ai(cid:374)tai(cid:374) cell"s shape & helps (cid:449)ith (cid:373)o(cid:448)e(cid:373)e(cid:374)t. Cytoskeleton: fibrous network of proteins that organizes the cellular components & facilitates cellular activities. *structures differ in size, structure, composition, function: support the cell, and preserves shape, inner framework, provides strength to cell, can easily disassemble and reorganise, network provides anchorage sites for enzymes+ organelles, motility & movement of components inside. Example: cilia & flagella, enable movement, contain pair of microtubules that can move relative to one another = bending. Prokaryotic cells: have cytoskeleton, but component fibers differ. During movement, projection called pseudopodia is formed from growth of microfilaments. P attaches to surface, then actin-myosin filaments contract, pulling cells forward: actin-myosin ring aids in cleavage furrow in mitosis. Ring contracts = parent cell split into two daughter cells: actin-myosin may be responsible for cytoplasmic streaming (circular movement of cytoplasmic fluid that facilitates an even distribution of substances within cell) Chloroplasts move in response to light: due to actin microfilaments.
