Lecture 3: features of host cells

Rough ER

closest to the nucleus, little network within the cytoplasm studded with ribosomes

Ribosomes

make proteins after binding to messenger RNA, attached to rough ER or free, rER make proteins for lumen where they are modified and folded

golgi complex

vesicles from rough ER bring proteins here where enzymes complete modifications they then are sent out to the cell

protein transport

some to cell membrane others to internal part of the cell

lysosomes

proteins are packaged into these, they digest complex biological molecules, enzymes for the lysosome function better at a pH of 5 so damage if the lysosome breaks is mitigated

mitochondria

where ATP is produced

cytoskeleton

microtubules, microfilaments and intermediate filaments provide structure and place for vesicles to move along

bulk transport

For larger molecule intake into the cell, does endocytosis and exocytosis

exocytosis

proteins packaged in secretory vesicles by golgi travel to membrane where they fuse and are released

endocytosis

material from the exterior enclosed in cavity from the plasma membrane by bulk phase or receptor mediated

receptor mediated endocytosis

receptors on cell membrane are activated and at clathrin coated pits caveolin forms a membrane pit (caveolae) inside the vesicle looses the clathrin coating

G1 phase

normal cellular growth, some cells never continue past and enter G0

S phase

chromosomes copied to prepare for division

G2

cell grows more and prepares for mitosis, checkpoint passed

M phase

mitosis occurs