Answer: Two flagella, one lateral and one longitudinal, with stiff cellulose plates on the cell wall.
- A Two flagella, one lateral and one longitudinal, with stiff cellulose plates on the cell wall
- B Largely absent flagella combined with a chitinous exoskeleton-like cell wall structure
- C Locomotion mainly by amoeboid movement using extending pseudopodia structures
- D An infectious spore-forming stage characteristic of their typical parasitic life cycle
Correct answer: A. Two flagella, one lateral and one longitudinal, with stiff cellulose plates on the cell wall
Explanation: Dinoflagellates are mostly marine and photosynthetic, bearing two flagella (one lateral, one longitudinal) and a cell wall with stiff cellulose plates. Some, like Gonyaulax, cause red tides.
Whittaker's five-kingdom system (1969) groups all cellular life by cell structure and nutrition; viruses, viroids, and lichens fall outside this system entirely since they aren't independently classifiable as one of the five.
Concept context
Whittaker's five kingdom system covering Monera, Protista, Fungi, plus viruses, viroids, and lichens. A foundational NEET chapter on how living organisms are grouped.