Answer: c
Explanation: Plants and animals need nitrogen to make proteins but they cannot take it in from the air. Because nitrogen is unreactive as a gas, it has to be transformed into a new molecule. When bacteria in the soil takes nitrogen from the air, it becomes nitrates. Finally, it can move through the food chain in this form.
Answer:
11: Independent variable
12: Sink
13: Depends on whether your teacher will let you play once a lesson is over but in most classrooms I would say it is not allowed
14:Theory
15: Objective
16: 3
Explanation:
3) C. Stomata, as I explained in my previous answer.
4) B. Nonvascular, low-hanging plants living in moist environs don't have to fight gravity nearly as much as tall ones do. So they needn't highly developed vessels to transport to their tips
5) B. Gravity, see above. The higher trees/plants grew, the further their apical structures were from ground water sources, so the lignin-supported, strong vascular tissue (phloem) allows the transport of water against gravity, using a capillary method (benefiting from the adhesive effect of water molecules).
improved water habitats for human recreation.
Answer:
Extreme warm weather, glacial melting, rising sea levels, Ocean Acidification,Animal Migration and Extinction of Species, The Increase of Health Issues and Costs.
