Cellular Transport

Question 1

What are the 3 Proteins Embedded in the Cell Membrane?

Answer 1

Transport: some proteins, called trans-membrane, transport molecules in or out of the cells
Recognition Sites/Identity Markers: Proteins that protrude from the membrane and act as recognition sites for certain molecules
Structural support: proteins which protrude and have cytoskeleton filaments to give structural support to the cell

Question 2

Passive Transport

Answer 2

A natural process which moves particles through air or water from high concentration to low concentration

Question 3

Simple Diffusion

Answer 3

Movement of particles down the concentration gradient (can go into or out of the cell)

Question 4

Facilitated Diffusion

Answer 4

Movement of molecules that are charged, polar or relatively large across the cell membrane
Can use carrier proteins or channels

Question 5

Osmosis

Answer 5

Diffusion of Water through the cell membrane

Water cannot diffuse directly due to its high polarity, usually uses aquaporins

Question 6

What are the 3 types of Osmosis?

Answer 6

Hypertonic: water concentration is higher inside the cell than outside leading to diffusion of water out of the cell
Isotonic: water concentration is equal
Hypotonic: water concentration is higher outside of the cell leading to diffusion into the cell

Question 7

Active Transport

Answer 7

Movement of particles up the concentration gradient (against the natural flow)
Requires energy

Question 8

How does ATP provide energy?

Answer 8

ATP is unstable and breaks into ADP and a free phosphate ion
Phosphate ion carries energy and tranfers it to a carrier protein
Desired molecule attaches to the carrier protein and the Phosphate ion detaches

Question 9

Bulk transport and its 2 types

Answer 9

Used to move large molecules or large amounts of molecules in and out of the cell
Form of active transport and therefore requires ATP
Endocytosis: moves large stuff into the cell
Exocytosis: moves large stuff out of the cell

Question 10

What are the 3 types of Endocytosis

Answer 10

Phagocytosis: used to bring in large clumps of material. Cell membrane pinches off and creates a vacuole
Pinocystosis: used to take in extracellular fluid. same principle as phagocytosis
Receptor-Mediated: used to take in specific types of molecules. when receptors are full, the cell creates a coated vesicle for transport