Final answer:
The three main types of life cycles in multicellular organisms are diploid-dominant, haploid-dominant, and alternation of generations life cycles.
Step-by-step explanation:
The three main types of life cycles in multicellular organisms are the diploid-dominant, haploid-dominant, and alternation of generations life cycles.
- In the diploid-dominant life cycle, the dominant phase is the diploid stage, where the organism has two sets of chromosomes. This is commonly observed in animals.
- In the haploid-dominant life cycle, the dominant phase is the haploid stage, where the organism has one set of chromosomes. This is commonly observed in fungi and some algae.
- In the alternation of generations life cycle, both the diploid and haploid stages are distinct and alternate in a regular pattern. This is commonly observed in plants.
An example of an organism that employs each life cycle: diploid-dominant - human, haploid-dominant - fungi, and alternation of generations - ferns.