Diplontic

Definition

Diplontic organisms spend the majority of their life cycle in the diploid state, where cells contain two sets of chromosomes. This is contrasted with haplontic life cycles, where the majority of the life cycle is spent in the haploid state.

5 Must Know Facts For Your Next Test

1. Diplontic life cycles are common in animals and some algae.
2. The diploid phase produces gametes through meiosis.
3. Fertilization between gametes restores the diploid chromosome number.
4. In diplontic organisms, mitosis occurs only in the diploid phase.
5. Seedless plants such as ferns exhibit a dominant sporophyte (diploid) phase.

Review Questions

• What is the main characteristic of a diplontic life cycle?
• How does fertilization affect the chromosome number in diplontic organisms?
• Which phase undergoes mitosis in a diplontic organism?

Related terms

Haplontic: Life cycle primarily in the haploid state with a short-lived diploid phase.

Sporophyte: The diploid generation that produces spores via meiosis in plants.

Gametophyte: The haploid generation that produces gametes through mitosis in plants.