Practice Questions

Water enters the central vacuole, pushing the protoplast against the tough cell wall; this builds turgor pressure, keeping the plant upright.

Lacking a rigid cell wall to resist hydrostatic pressure, animal cells absorb water via osmosis until the plasma membrane ruptures.

Animal cells incorporate cholesterol into their membranes to regulate fluidity across temperatures; plants use alternative sterols (phytosterols).

The middle lamella acts as a cellular glue between neighboring plant cells, composed primarily of sticky sticky pectin compounds.

Lignin is a complex, non-carbohydrate aromatic polymer deposited in secondary plant cell walls, rendering them woody, waterproof, and rigid.

The rigid cell wall prevents pinching; instead, the phragmoplast guides Golgi vesicles to fuse at the equator, forming a new cell plate from the inside out.

Animal cells form a contractile ring of actin and myosin filaments that pinches the plasma membrane inward, creating a cleavage furrow.

Leukoplasts are non-pigmented plastids found in non-photosynthetic plant tissues (like roots or tubers) that store starches (amyloplasts) or fats.

The rigid, box-like cellulose cell wall forces plant cells to maintain structured, geometric, or rectangular morphologies.

The development of a massive, turgid central vacuole forces the cytoplasm and the nucleus to the periphery against the plant cell wall.