Cell wall Knowledge-Based Download PDF

Questions

1. 1.

   When placed in a hypotonic environment, plant cells absorb water by osmosis without bursting, whereas animal cells typically undergo lysis. Which feature or function of the cell wall directly prevents plant cells from bursting under these conditions?

   • A) Its selectively permeable lipid bilayer actively pumps excess water back into the extracellular environment.
   • B) Its contractile protein network actively expels incoming water into neighboring vascular channels.
   • C) Its rigid structural framework exerts mechanical counterpressure against internal turgor pressure.
   • D) Its outer hydrophobic wax layer creates an impermeable barrier that completely halts water influx.
2. 2.

   Which structures penetrate the plant cell wall to establish cytoplasmic continuity and facilitate intercellular communication between neighboring cells?

   • A) Gap junctions
   • B) Plasmodesmata
   • C) Desmosomes
   • D) Tight junctions
3. 3.

   In plant cells that produce a secondary cell wall, where is this layer specifically deposited relative to existing structures, and which polymer typically reinforces it?

   • A) Outside the middle lamella; pectin
   • B) Between the primary cell wall and the middle lamella; cutin
   • C) Directly on the external surface of the primary cell wall; suberin
   • D) Between the plasma membrane and the primary cell wall; lignin
4. 4.

   Which layer of the plant cell wall complex is rich in pectin and functions as an adhesive layer that cements adjacent cells together?

   • A) Secondary cell wall
   • B) Middle lamella
   • C) Plasma membrane
   • D) Tonoplast
5. 5.

   Which of the following statements correctly identifies the primary structural carbohydrate of the plant cell wall and its main role in plant cells?

   • A) It is composed primarily of cellulose and provides mechanical support to prevent osmotic lysis under hypotonic conditions.
   • B) It is composed primarily of glycogen and functions as a selective barrier regulating solute transport into the cytoplasm.
   • C) It is composed primarily of peptidoglycan and synthesizes adenosine triphosphate through cellular respiration.
   • D) It is composed primarily of chitin and forms a flexible fluid bilayer that facilitates endocytosis.