Membrane Transport, Diffusion & Osmosis — Drills · Grade 7 Science
Chapter: Cells, Transport & Cellular EnergyWhat these drills covers
By the end of Membrane Transport, Diffusion & Osmosis you should be able to:
- I can explain membrane transport, diffusion & osmosis.
- I can use evidence, a model, and stated assumptions to support a biological explanation.
4 questions, multiple choice, numeric and written answer, each with a worked explanation.
Vocabulary used: diffusion, concentration, osmosis, selectively permeable, equilibrium.
Problem 1
What moves in the simple osmosis model?
- Only cell walls
- Water across the selective membrane
- Every solute equally
- Whole organ systems
Answer and explanation
Water across the selective membrane
Osmosis concerns net water movement across a selectively permeable membrane.
Problem 2
A model compartment has 12 solute units in 3 volume units. Find concentration.
Answer and explanation
4 solute units/volume unit
12/3=4 in the stated model units.
Problem 3
Why can particle count alone fail to show concentration?
Answer and explanation
Concentration depends on both amount and volume; counts in unequal volumes are not directly comparable.
Problem 4
What must be known before predicting osmosis?
Answer and explanation
Which materials can cross, their concentrations, and relevant pressure or other conditions; a membrane is not universally permeable.