Osmosis And Tonicity Worksheet Answer Key 2020-2024 - Fill and ... - Free Printable

Explanation:
We are given two diagrams showing osmosis across a semi-permeable membrane. In both cases, the membrane allows water to pass but not solute (like sugar or salt). Osmosis is the movement of water from an area of lower solute concentration to an area of higher solute concentration — that is, from *more water* to *less water* (since more solute means less free water).

Let’s analyze each diagram carefully.

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Diagram 1:
- Left side: 50% glucose solution
- Right side: 0% glucose (pure water)
→ So left has high solute (glucose), right has no solute.
→ Water will move from right to left (from pure water into the 50% glucose solution) to try to balance concentrations.

Now answer the questions for Diagram 1:

A. What is the % of water inside the cell?
→ The cell is the left side (50% glucose), so water = 100% − 50% = 50% water

B. What is the % of water outside the cell?
→ Outside is pure water → 100% water

C. Will water move in?
→ Yes, because outside has more water (100%) than inside (50%), and water moves toward higher solute (left side). So water moves in → Yes

D. If so, in what direction will water move?
→ From outside to inside → Into the cell

E. Will glucose diffuse?
→ Glucose cannot cross the semi-permeable membrane (as stated in instructions), so No

F. Will the cell shrink or swell?
→ Water enters → cell swells → Swell

G. How do you know?
→ Because water moves into the cell due to osmosis (from low solute to high solute side)

H. This diagram shows the cell in a(n) [hypotonic / hypertonic / isotonic] solution.
→ The solution outside has *lower* solute concentration than inside → it's hypotonic
(Recall: *hypo* = less solute → water enters cell)

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Diagram 2:
- Left side: 20% glucose
- Right side: 40% glucose
→ So left has less solute, right has more solute
→ Water will move from left to right (from 20% glucose side into 40% glucose side)

Now answer the questions for Diagram 2:

A. What is the % of water inside the cell?
Assume the cell is the left side (20% glucose) → water = 100% − 20% = 80% water

B. What is the % of water outside the cell?
Outside = 40% glucose → water = 60% → 60% water

C. Will there be a net change in water concentration?
→ Yes, because concentrations differ → water will move until equilibrium (if possible) → Yes

D. Will water move in?
→ “In” means into the cell (left side). But water moves *out* of the cell (left → right), so No

E. Will glucose diffuse?
→ No — membrane is semi-permeable, blocks glucose → No

F. Will the cell shrink or swell?
→ Water leaves the cell → cell shrinks → Shrink

G. How do you know?
→ Water moves out of the cell toward the higher solute concentration (right side)

H. This diagram shows the cell in a(n) [hypotonic / hypertonic / isotonic] solution.
→ Outside has *higher* solute (40%) than inside (20%) → solution is hypertonic
(*hyper* = more solute → water leaves cell)

I. If the diagram shows the cell in an isotonic solution, what would you see?
→ Isotonic means equal solute on both sides → no net water movement → cell size unchanged
So: No change in cell size; water moves equally in both directions (no net movement)

J. What would you see after several hours? Why?
→ In Diagram 1 (hypotonic): cell swells, possibly bursts (lysis) if animal cell
→ In Diagram 2 (hypertonic): cell shrinks (crenation in animal cells)
But since question says “the diagram” (singular), likely referring to Diagram 2 (since I was just asked about isotonic), but actually J follows I, and I is general. However, looking at the structure, J is part of Diagram 2 section (it’s labeled under Diagram 2, question J). So for Diagram 2:
→ Cell would shrink because water keeps leaving until concentrations equalize (or membrane limits further change).
Why? Because outside is hypertonic → water leaves cell by osmosis.

But wait — the worksheet labels questions clearly:
- Diagram 1: Q A–H
- Diagram 2: Q A–J
So J is for Diagram 2.

Thus for J:
After several hours, the cell would shrink (lose water) because the external solution has higher solute concentration, so water continues moving out until equilibrium or physical limits.

Now verify all answers:

Diagram 1:
A. 50%
B. 100%
C. Yes
D. Into the cell
E. No
F. Swell
G. Water moves from low solute to high solute (outside to inside)
H. Hypotonic

Diagram 2:
A. 80%
B. 60%
C. Yes
D. No
E. No
F. Shrink
G. Water moves from low solute (inside) to high solute (outside)
H. Hypertonic
I. Cell size stays the same; no net water movement
J. Cell shrinks because water leaves due to osmosis into the hypertonic solution

All consistent.

Final Answer:
Diagram 1:
A. 50%
B. 100%
C. Yes
D. Into the cell
E. No
F. Swell
G. Water moves toward higher solute concentration (into the cell)
H. Hypotonic

Diagram 2:
A. 80%
B. 60%
C. Yes
D. No
E. No
F. Shrink
G. Water moves toward higher solute concentration (out of the cell)
H. Hypertonic
I. No change in cell size; water moves equally in both directions (no net movement)
J. The cell would shrink because water leaves the cell by osmosis into the hypertonic solution.