Answer: They secrete protease and other hydrolytic enzymes to digest prey, primarily gaining nitrogen and phosphorus to supplement growth in nutrient-poor environments.
- A They rely on passive decomposition by ambient soil microbes to break down trapped insects, slowly releasing trace minerals the plant then absorbs over several weeks
- B They secrete protease and other hydrolytic enzymes to digest prey, primarily gaining nitrogen and phosphorus to supplement growth in nutrient-poor environments
- C They absorb potassium and other cations released by their prey, though this contributes relatively little toward meeting their overall nitrogen requirements
- D They mechanically trap and crush their prey using specialized leaf structures, with most nutrient absorption happening afterward through the root system
Correct answer: B. They secrete protease and other hydrolytic enzymes to digest prey, primarily gaining nitrogen and phosphorus to supplement growth in nutrient-poor environments
Explanation: Carnivorous plants secrete digestive enzymes (proteases, esterases, nucleases) onto captured prey. They absorb the digestion products - mainly nitrogen (as amino acids/NH4+) and phosphorus - to supplement their photosynthetically produced carbon. This adaptation allows survival in N-poor, acidic, waterlogged soils.
Atmospheric N₂ is fixed into ammonia by nitrogen-fixing bacteria (protected from oxygen by leghaemoglobin in root nodules), converted to nitrate via nitrification for plant uptake, and eventually returned to the atmosphere as N₂ via denitrification, completing the cycle.
Concept context
Essential mineral elements, their roles and deficiency symptoms. Nitrogen fixation and soil nutrition.