6.3: Plant Anatomy

Question 1

What are the three basic plant organs, and what are their functions?

Answer 1

1. Roots:
   ○ Anchor the plant in the soil.
   ○ Absorb water and nutrients (e.g., nitrogen, phosphorus).
   ○ Store carbohydrates and other nutrients.
   2. Stems:
   ○ Support leaves and reproductive structures.
   ○ Transport water and nutrients via xylem and phloem.
   ○ May store food (e.g., tubers).
   3. Leaves:
   ○ Primary site of photosynthesis.
   ○ Exchange gases (CO₂ and O₂) through stomata.
   ○ Regulate water loss via transpiration.

Question 2

What are the three plant tissue systems, and what are their components and functions?

Answer 2

1. Dermal Tissue:
   ○ Epidermis: Outer protective layer; includes cuticle to reduce water loss.
   ○ Periderm: Replaces the epidermis in woody plants.
   2. Vascular Tissue:
   ○ Xylem: Transports water and dissolved minerals from roots to shoots.
   ○ Phloem: Transports sugars and other organic compounds.
   3. Ground Tissue:
   ○ Functions in photosynthesis, storage, and support.
   ○ Includes parenchyma, collenchyma, and sclerenchyma cells.

Question 3

: What are the different types of cells in ground tissue, and what are their functions?

Answer 3

1. Parenchyma Cells:
   ○ Perform photosynthesis in leaves.
   ○ Store starch and nutrients in roots.
   2. Collenchyma Cells:
   ○ Provide flexible support for growing plant parts (e.g., stems, leaves).
   3. Sclerenchyma Cells:
   ○ Provide rigid support with lignin-reinforced walls.
   ○ Found in mature plant parts (e.g., fibers and sclereids).