Ch. 4 Diffusion/Osmosis

Question 1

Solution (2)

Answer 1

• homogeneous mixture (particles are distributes evenly throughout)

(Gases, liquids, and solids all form solutions)
(An alloy of metals is a common metallic solution)

Question 2

solutions are composed of ________ known as _________and_________

Answer 2

2 phases:

Solvent and solute

Question 3

Solvent

Answer 3

Most abundant phase

Question 4

Solute

Answer 4

• the phase present in the lesser amount

* dissolves in solvent

Question 5

Alloy

Answer 5

A solution of 2 or more metals

Ex: steel

Question 6

Dynamic equilibrium

Answer 6

The equilibrium is considered dynamic since there is still movement of molecules but their distribution remains balanced

Question 7

Diffusion

Answer 7

• no energy required

* goes from high concentration to low concentration

Question 8

Concentration gradient

Answer 8

Movement is “down a concentration radiant” since the molecules move from areas of higher concentration to areas of low concentration

Question 9

Agar (3)

Answer 9

Gel - like substance
extracted from seaweed
often used in laboratory experiments

Question 10

A MOLE of substance is ________

Answer 10

The amount of a substance equal to the molecular mass of that substance (expressed in grams)

Total amount of a substance = molecular mass

Question 11

Molecular mass

Answer 11

Determined by adding the atomic mass of each element in a compound

Question 12

Osmosis (5)

• definition
• form of _______
• ________ process
• requires ____ energy
• follows the ________ of molecules

Answer 12

• the movement of WATER molecules across a plasma membrane

• form of diffusion
• passive process (like diffusion)
• requires no energy
• follows the concentration gradient of water molecules

Question 13

Tonicity

Answer 13

Used when COMPARING THE CONCENTRATION OF SOLUTES inside and outside the plasma membrane

Question 14

Hypotonic

Answer 14

Environment exists outside the cell when the solute concentration outside the cell is lower than the solute concentration in the the cells cytoplasm

• when the concentration outside is LOWER than inside

• swells
• “blows up like a hypo”

Question 15

Hypertonic

Answer 15

When the solute concentration outside the cell is higher than that inside the cell

• when the concentration outside is HIGHER than the inside

“Hyper” - high amount of solute
- shrinks

Question 16

Hypothesis

Answer 16

• prediction

- first step in the scientific method

Question 17

Scientific method

Answer 17

• procedures and waiting time are the experiment part

Question 18

Conclusion of the scientific method

Answer 18

Relate to the hypothesis

- either uphold or discount the prediction

Question 19

Differently / selectively permeable

Answer 19

only certain materials can move across them

Question 20

Plasma membrane ***

Answer 20

In animals the plasma membrane is usually the outermost limit of the cell

• have fairly rigid cell wells
• made of cellulose as their outer limit
• the plasma membrane immediately interior
• (like blood cells) if they have no protective cell wall and will swell and burst (process called lysis) under hypotonic conditions
• plant cells central vacuole will fill and press the plasma membrane against the interior of the cell wall

Question 21

Turgid **

Answer 21

The cells condition

Question 22

Turgor pressure

Answer 22

The resulting water pressure

Question 23

Plasmolysis

Answer 23

in hypertonic conditions:

• an animal cell will shrink
• a plant cell undergoes plasmolysis as its plasma membrane is pulled away from the cell wall when the central vacuole is emptied