diffusion and osmosis and active transport

Question 1

What is diffusion?

Answer 1

Diffusion is the transfer of energy from an area of high concentration to an area of low concentration. It travels down a concentration gradient and the larger the concentration gradient, the quicker the rate of reaction. It is a passive reaction mad it doesn’t require energy. Only takes place in liquids and gasses as particles only vibrate in solids.

Question 2

Describe the gas exchange process between the alveoli and the bloodstream

Answer 2

CO2 is diffused from the bloodstream and back into the alveoli.
O2 is diffused from the alveoli into the bloodstream to be taken around the body.

Question 3

What is osmosis?

Answer 3

The movement of WATER from a dilute (high water concentrated) solution to a concentrated (low water concentration) solution. It works down a concentration gradient and the particles are separated through a partially permeable membrane. It is a passive reaction.

Question 4

What is a hypertonic solution?

Answer 4

Dilute/high water concentrated solution.

Question 5

What is an isotonic solution?

Answer 5

A balanced solution

Question 6

What is a hypotonic solution?

Answer 6

A concentrated/low water concentrated solution.

Question 7

What happens when a cell is put in a hypertonic solution?

Answer 7

Because the solution has a low water concentration, the water leaves via osmosis meaning the cell wilts.

Question 8

What happens when a cell is put into an isotonic solution?

Answer 8

The same amount of water both exits and leaves. The cell is in balance because the water concentration outside the cell is the same as inside the cell.

Question 9

What happens when a cell is put into a hypotonic solution?

Answer 9

Because the solution is concentrated (low water concentration) that means that water enters the cell and the cell swells and eventually bursts.

Question 10

Define a solute

Answer 10

Solid. A substance we put into a liquid. E.g. Sugar

Question 11

Define a solution

Answer 11

What happens when the solute dissolves in the solvent.

Question 12

Define concentration

Answer 12

How strong a solution is

Question 13

Define a dilute solution

Answer 13

There are more water particles. High water concentration.

Question 14

Define a concentrated solution

Answer 14

Less water particles. Low water concentration.

Question 15

What happens to the cells inthe plant if there is enough water?

Answer 15

The plant cell vacuole is full of water and pushes against the cell wall. The cell wall stops the cell from bursting. We say that the cell is turgid.

Question 16

Define a weak solution

Answer 16

More water particles/dilute

Question 17

What happens when too much water enters or leaves a red blood cell?

Answer 17

In blood there is a substance called plasma. When it is placed in a CONCENTRATED SOLUTION (low water concentration), cells will shrivel as water is exiting the rbc to go into the solution. When the rbc is placed into distilled water (high water concentration) the cells swell as water is being added

Question 18

Describe the potato experiment

Answer 18

We cut potato cylinders and tested the rate of osmosis. When the potato gained weight the solution it was put into had a higher water solution as compared to inside the potatoes cells. When the potato lost weight the solution it was put in had a lower water concentration as compared to inside the potato cells. The rate of reaction was quickest at both the biggest and lowest concentrations as the concentration gradient is largest.

Question 19

What is active transport?

Answer 19

Active transport is a process that does require energy as it goes against the concentration gradient from an area of low concentration to an area of high concentration. Carrier proteins carry the molecules through. Carrier proteins require energy that comes from respiration that flea place in mitochondria.

Question 20

Give an example of active transport.

Answer 20

If the concentration of minerals in the soil is greater than inside the plant itself. The minerals would move inside the cell via active transport.

Question 21

What is the effect of temperature on active transport?

Answer 21

Because active transport requires proteins and enzymes are proteins. If we heat up the molecules the enzymes/carrier proteins will denature meaning the reaction will stop.