Lecture 5 Flashcards
vesicular transport
move large particles, fluid droplets, or numerous molecules at once through the membrane in vesicles– bubble-like enclosures of membrane; utilizes motor proteins energized by ATP
Endocytosis: ________
types:
process of active transport by which molecules are moved from outside to inside of the cell
phagocytosis: takes large particles
pinocytosis: takes fluid & solutes
receptor-mediated endocytosis: whatever is getting taken in has receptors
exocytosis
process of active transport by which molecules move from inside to outside of the cell
transcytosis
transport of material across the cell by capturing it on one side and releasing it on the other; pinocytosis or endocytosis moves it into the cell and exocytosis moves it out the other side
cytoskeleton (non-membranous): network of protein filaments and cylinders
-determines cell _____, supports ______, organize cell contents, directs movement of materials within cell, contributes to movements of the ____ as a whole
shape, structure, cell
The cytoskeleton contains
1.
2.
3.
- actin filaments
- microtubules
- intermediate filaments
organelles: internal structure of a cell, carry out specialized _______ tasks suspended in the jelly like _______
2 types:
metabolic; cytoplasm
membranous and non-membranous
The Nucleus (membranous)
nuclear envelope:
-_______ membrane around nucleus
-perforated by nuclear _____ formed by rings of proteins: regulate molecular traffic through envelope
_____ the two membrane layers together
nucleoplasm- material in nucleus
-_______ (thread-like) composed of DNA and protein
-Nucleoli: masses where _______ are produced
double
pores
hold
chromatin
ribosomes
Rough Endoplasmic Reticulum (membranous)
-system of channels (_____) enclosed by membrane
-flattened sacs covered with ________
-continuous with outer membrane of nuclear envelope, often largest organelle
-produces ________ and ______ of nearly all cell membranes
-synthesizes ______ that are packaged in other organelles or secreted form cell
cisterns
ribosomes
phospholipids; proteins
proteins
Smooth Endoplasmic Reticulum (membranous)
-lacks ribosomes
-cisterns more _______ and branching
-cisterns thought to be continuous with rough ER
-synthesizes ______ and other _____
-_______ storage
-detoxifies _______ and other drugs
-functionally different parts of the same network
tubular
steroids; lipids
calcium
alcohol
Ribosomes (non-membranous)
-small granules of ______ and _____
-found in nucleoli, in cytosol, and on outer surfaces of rough ER and nuclear envelope
-they “____” coded genetic messages (mRNA) and assemble amino acids into _______ specified by the code
protein; RNA
read
proteins
Golgi Complex (membranous)
-a system of cisterns that synthesizes _______ and puts finishing touches on _______ synthesis
-receives newly synthesized ________ from rough ER
-sorts proteins, splices some, adds carbohydrate moieties to some, and _______ them into membrane-bound Golgi _______
-some vesicles become ______
-some vesicles ______ to plasma membrane and fuse to it
-some become _______ vesicles that store a protein product for later release
-carbohydrates; protein
-proteins
-packages
-lysosomes
-migrate
-secretory
lysosomes (membranous)
-package of ________ bound by a membrane
Functions:
-intracellular ________ ________ of proteins, nucleic acids, complex carbohydrates, phospholipids, and other substances
-autophagy:
-autolysis:
enzymes
hydrolytic digestion
-digestion of cells surplus organelles
-“cell suicide” digestion of its own cell (not purposeful)
autophagy
digestion of cell’s surplus organelles
autolysis
“cell suicide”: digestion of a surplus cell by itself (enzymes leak out and destroys the cell)
