Question

Both sporophyte and gametophyte are multicellular in which life cycle?

• A. Haplontic
• B. Diplontic
• C. Haplodiplontic and Diplontic
• D. Haplodiplontic and Diplohaplontic

Hint:

Remember:
• Haplontic \(\rightarrow\) Gametophyte dominant
• Diplontic \(\rightarrow\) Sporophyte dominant
• Haplodiplontic \(\rightarrow\) Both phases multicellular

Answer 1

The Correct Option is D

Concept: Plant life cycles are characterized by alternation of generations involving two multicellular phases:
• Gametophyte (haploid)
• Sporophyte (diploid) The relative dominance of these phases determines the type of life cycle.

Step 1: Study the haplontic life cycle.
In a haplontic life cycle: \[ \text{Only gametophyte is multicellular} \] while the sporophyte is represented only by the zygote. Therefore both phases are not multicellular.

Step 2: Study the diplontic life cycle.
In a diplontic life cycle: \[ \text{Only sporophyte is multicellular} \] The gametophytic phase is represented only by gametes. Thus both phases are not multicellular.

Step 3: Study the haplodiplontic life cycle.
In this life cycle: \[ \text{Both gametophyte and sporophyte are multicellular} \] and may be independent of each other.

Step 4: Apply the concept.
Since both multicellular phases coexist only in haplodiplontic (diplohaplontic) life cycles, the correct answer is \[ \boxed{\text{Haplodiplontic and Diplohaplontic}} \]