Cell Transport - Passive & Active Transport

Question 1

What are the TWO types of cell transport?

Answer 1

Passive transport & Active transport

Question 2

PASSIVE TRANSPORT

Answer 2

Does NOT require ATP (energy). Moves ALONG the concentration gradient.

Question 3

What are the THREE types of passive transport

Answer 3

Diffusion
Facilitated Diffusion
Osmosis

Question 4

Diffusion (passive transport)

Answer 4

In diffusion particles will randomly spread out from a high concentration to a low concentration. This sets up a concentration gradient. Small uncharged molecules like O2, CO2, glucose, etc can freely pass through the membrane and go down the concentration gradient.

Question 5

Factors that affect diffusion (passive transport)

Answer 5

1. State (gasses diffuse faster than liquids)
2. Size (small particles = faster diffusion)
3. Temperature (higher temp = faster diffusion)
4. Difference of high concentration and low concentration

Question 6

Facilitated Diffusion (passive transport)

Answer 6

• Many ions and molecules cannot diffuse directly through the membrane because they are either too big or carry a charge.
• They need a protein channel or pore through the membrane to enter the cell.
• Transport proteins are specific: they only allow certain molecules to pass
  Transport large molecules, or ions and molecules with a charge (e.g Na+, K+)

Particles still diffuse at random, but must pass through the channel.

Question 7

Osmosis (passive transport)

Answer 7

Osmosis is the process of when water is diffused from a high concentration of water to a low concentration of water through a semi-permeable membrane

Question 8

Osmoregulation

Answer 8

Cells are surrounded by water so they need to control the movement of water across the membrane

Question 9

Hypotonic (low solute concentration, high water)

Answer 9

The concentration of solutes inside the cell is lower than outside of the cell. When a cell is put in a solution with a higher solute concentration and low water potential than the inside of the cell, water will move out of the cell from an area of high water to an area of low water. The cell loses water.

Question 10

Hypertonic (high solute concentration, low water)

Answer 10

The concentration of solutes inside the cell is lower than outside of the cell. When a cell is put in a solution with a higher solute concentration and low water potential than the inside of the cell, water will move out of the cell from an area of high water to an area of low water. The cell loses water.

Question 11

What are the THREE types of Active transport?

Answer 11

1. Protein pump
2. Endocytosis
3. Exocytosis

Question 12

Active Transport

Answer 12

The movement of particles against a concentration gradient, from an area of low concentration to an area of higher concentration. This process requires ATP energy and moves AGAINST the concentration gradient.
- chemical energy in a cell is stored as ATP (Adenosine Triphosphate)
- When ATP to converted to ADP, the reaction released energy. This energy is used to power protein pumps and move molecules across the membrane.
- Active transport is SELECTIVE and moves specific molecules from an area of low concentration to an area of high concentration.

Question 13

Active Transport Process

Answer 13

• Active transport is performed by ion pumps and carrier proteins in the cell membrane.
• Specific substances bind to the carrier protein.
• ATP also binds and the carrier protein converts ATP to ADP, releasing energy.
• Energy causes the carrier protein to change shape, ejecting the substance the other side of the membrane.
• E.g absorption of glucose, moving charged ions.

Question 14

Active Transport - Sodium Potassium ion Pump

Answer 14

Important for the functioning of nerve cells.
- Moves three NA+ out of the cell, and two K+ into the cell, using ATP for energy.

Question 15

Active Transport - What are the two types of Cytosis

Answer 15

Endocytosis & Exocytosis

Question 16

Active Transport - Endocytosis

Answer 16

The process by which substances are taken IN by the cell

Question 17

What are the two types of endocytosis?

Answer 17

1. Phagocytosis
2. Pinocytosis

Question 18

Endocytosis - What is PHAGOCYTOSIS

Answer 18

Solid particles

Question 19

Endocytosis - What is PINOCYTOSIS

Answer 19

Fluids/Liquids

Question 20

Exocytosis

Answer 20

The process by which substances are REMOVED from the cell.
e.g removing waste products
e.g excreting hormones

Substances are stored or packaged into membrane-bound vesicles within the cell. The vesicles are transported to the inner surface of the plasma membrane.

The vesicle membrane merges with the cell membrane, opening the vesicle tot he extra-cellular environment, and releasing the substances.

Question 21

Active Transport - What is the process of active pumps in the membrane?

Answer 21

The process of active transport involves specific protein pumps. The protein pumps are made up of specific proteins called trans-membrane proteins. These pumps first make a complex with the substance to be transported across the membrane, using the energy derived from ATP.