Cells and Tissues

Question 1

What is Primary Active Transport?

Answer 1

The transport across the membrane is energised my ATP.
It moves from low concentration to high concentration against the concentration gradient.
(This is the opposite to diffusion and osmosis) because this is not the natural direction.
Energy is required to make it work (ATP)

Question 2

What is Secondary Active Transport? (Contransport)

Answer 2

Couples the transport of one solute (Na+ and/ or H+) down it’s concentration gradient with movement of another up/ against it’s concentration gradient.
Because a Na+ or H+ is established by primary active transport, secondary active transport indirectly uses the energy obtained from the hydrolysis of ATP.

Question 3

If the transporters move both substances in the same direction they are are called____

Answer 3

Symporters

Question 4

If transporters move both substances in the opposite direction they are called____

Answer 4

Antiporters

Question 5

What is vesticular transport?

Answer 5

When fluids containing large particles and macromolecules are transported across cellular membranes inside vesicles- bubble like membranous sacs.

Question 6

Vesicular transport of substances moving into a cell is called?

Answer 6

Endocytosis

Question 7

What are three types of endocytosis?

Answer 7

• Receptor Mediated Endocytosis: extracellular substances binding to specific receptors (ligands)
• Phagocytosis: is large solid particles (to eat)
• Bulk phase endocytosis ( Pinocytosis): ECF containing solutes (to drink)

Question 8

Vesicular transport of substances moving out of a cell is called?

Answer 8

Exocytosis

Question 9

What substances are commonly excreted from cells via exocytosis?

Answer 9

Hormones, Neurotransmitters, Mucous, Waste

Question 10

What is osmosis?

Answer 10

Passive movement of water molecules across a selectively permeable membrane from an area of higher to lower water concentration until equilibrium is reached.

Question 11

What is Diffusion?

Answer 11

Movement of molecules or ions down a concentration gradient due to their kinetic until they reach equilibrium.

Question 12

What is facilitated diffusion?

Answer 12

Passive movement of a substance down its concentration gradient through the lipid bilayer by transmembrane proteins that functions as channels of carriers.

Question 13

What is simple diffusion?

Answer 13

Passive movement of a substance down its concentration gradient through the bilayer of the plasma membrane without the help of membrane transport proteins.

Question 14

What is passive processes?

Answer 14

Movement of substances down a concentration gradient until equilibrium is reached; do not require cellular energy in the form of ATP.

Question 15

What is active processes?

Answer 15

Movement of substances against a concentration gradient: requires cellular energy in the form of ATP.

Question 16

What is Endocytosis?

Answer 16

Movement of substances into a cell in vesicles.

Question 17

What is exocytosis?

Answer 17

Movement of substances out of a cell in secretory vesicles that fuse with the plasma membrane and release their contents into the extracellular fluid.

Question 18

What is Transcytosis?

Answer 18

Movement of a substance through a cell as a result of endocytosis on one side and the exocytosis on the opposite side.

Question 19

Resting Membrane Potential

Answer 19

• A voltage difference on either side of the cell membrane, particularly important in muscle and nerve cells.
• Typically ranges from -50 to -90 mV depending on the cell type, indicating that the inside of of the cell is negative compared to the outside which is positive.

Question 20

Which are the key ions on each side of the cell membrane creating the voltage difference?

Answer 20

Inside: K+ and large negatively charged proteins and small amounts of Na+

•Outside: Na+, Cl and some K+

Question 21

What is the organelle that moves over a cell’s surface?

Answer 21

Cilia

Question 22

Which organelles produces most of a cells ATP?

Answer 22

Mitochondria