Question

The larva stage shown by coelenterate is called (a) Amphiblastula (b) Parenchymula (c) Planula (d) All of these

Short answer

The larva stage shown by coelenterate is called Planula (c).

Step-by-step solution

Identify the requirement of the question

The question is straightforward and asks for the larva stage of coelenterate. This is a direct recall from your biology lessons or textbook and it's about remembering facts, not solving a problem or proposition.

Recall Information

This question requires recall of fact. The coelenterate's larva stage is called 'Planula'. You would know this if you have correctly learned and remembered your biology related to coelenterate's life cycle.

Key concepts

Planula

The 'Planula' stage plays a crucial role in the life cycle of coelenterates, which are a fundamental group of aquatic animals known for their simple body structure. A planula is typically a free-swimming and flattened larval form that arises post-fertilization. Coelenterates reproduce both asexually and sexually, and after the gametes have united, they form a zygote, which then develops into a planula larva.
This stage is pivotal as it allows for the dispersion of the species within the aquatic environment. The planula, propelled by cilia, swims in the water until it finds a suitable substrate to settle upon. Once it attaches to a surface, it undergoes a remarkable transformation known as metamorphosis, where it develops into a polyp, thereby kick-starting the next phase of its complex life cycle.
Understanding the planula larva is not only important for biology students but also for individuals interested in marine biology and ecology, as the dispersal and settlement of planulae can significantly affect the distribution of coral reefs and other vital marine ecosystems.

Biology NEET Exam

The Biology NEET exam, or National Eligibility cum Entrance Test, is a highly competitive entrance examination in India for students aspiring to pursue undergraduate medical and dental courses. This comprehensive test assesses a candidate's knowledge across various biology topics, including genetics, ecology, human physiology, and of course, the diversity of life where understanding the life cycles of different species like coelenterates is essential.
Questions related to coelenterates, including their larva stage 'Planula', often appear in the NEET exam. Aspiring medical professionals need to master such detailed biological concepts, as the examination extensively covers the taxonomy and life processes of various organisms. Remembering the facts, such as the planula stage of coelenterates, can make a significant difference in a student's score. Rigorous study and a thorough understanding of biology not only aid in excelling in NEET but also lay a strong foundation for future medical studies.

Coelenterates Life Cycle

The life cycle of coelenterates is fascinating and involves distinct stages that showcase biological complexity and diversity. Coelenterates, including creatures like jellyfish, corals, and sea anemones, exhibit a life cycle that typically includes both a polyp stage and medusa stage in some species.
The life cycle begins when mature medusae release sperm and eggs into the water, leading to external fertilization. The resulting planula larvae subsequently settle onto a substrate and develop into polyps. These polyps may reproduce asexually through budding, fission, or stolons, leading to the formation of new, genetically identical polyps.
Some polyps undergo a process called strobilation, where segments of the polyp stack up to form medusae, which will eventually break off and become free-swimming. This alternation between the sessile polyp and the free-swimming medusa is known as 'alternation of generations,' a characteristic pattern for many coelenterates. This life cycle is not only critical for species propagation and genetic diversity but is also an important concept in evolutionary biology.