Question

q3. what would happen to an egg in an iso - tonic solution? explain using your knowledge of osmosis, solutes, and concentration gradients.
q4. critical thinking question: animal cells prefer isotonic solutions and plant cells prefer hypotonic solutions to maintain homeostasis (\balance\). what might be the reasoning behind this? what organelles do plant cells have that animal cells do not?

Explanation:

For Q3, in an isotonic solution, there is no net movement of water across the egg - cell membrane due to equal solute concentrations inside and outside the cell, so the egg's size and shape remain unchanged. For Q4, animal cells prefer isotonic solutions because in hypertonic solutions they lose water and shrink (crenation), and in hypotonic solutions they gain water and may burst (lysis). Maintaining homeostasis is crucial for proper cell function. Plant cells prefer hypotonic solutions as they have a cell wall that can withstand the turgor pressure generated when water enters the cell, which helps maintain plant rigidity. Organelles like the vacuole in plant cells play a role in regulating water balance and maintaining cell turgor.

Answer:

Q3: The egg's size and shape remain unchanged because there is no net movement of water due to equal solute concentrations inside and outside the cell (isotonic means equal solute - water concentration gradient).
Q4: Reason for preference: Animal cells need to maintain a stable internal environment to function properly. Extreme water loss or gain can disrupt cellular processes. Organelles in plant cells: The large central vacuole stores water and helps maintain turgor pressure, and chloroplasts (for photosynthesis) and cell walls also contribute to the cell's ability to handle hypotonic conditions.