Dominant phase in life cycle of most algae and fungi is

Options

A. Haploid
B. Diploid
C. Triploid
D. Tetraploid.

Answer

**Step-by-Step Solution:**

1. **Understanding Life Cycles**: In the life cycles of organisms, there are typically two main phases: the haploid phase and the diploid phase. The haploid phase contains one set of chromosomes (n), while the diploid phase contains two sets of chromosomes (2n).

2. **Identifying the Dominant Phase**: In most algae and fungi, the dominant phase of their life cycle is the haploid phase. This means that the majority of their life cycle is spent in the haploid state.

3. **Gametophyte Stage**: The haploid phase is often referred to as the gametophyte stage. In this stage, the organism produces gametes (sperm and eggs) through mitosis.

4. **Transition to Diploid Phase**: The haploid phase alternates with the diploid phase, which is initiated when two gametes fuse to form a zygote. The zygote is diploid (2n) and undergoes meiosis to produce haploid spores, which will grow into new gametophytes.

5. **Conclusion**: Since the dominant phase in the life cycle of most algae and fungi is the haploid phase, the correct answer to the question is option (a) haploid.

**Final Answer**: The dominant phase in the life cycle of most algae and fungi is (a) haploid.

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