Question 1: The correct answer should be the one that shows the producer first, (->) followed by the herbivore, (->) with the carnivore last.
Producers are organisms that harvest their own 'food' using things like the sunlight and water. Examples of producers are grass and other vegetation.

The herbivore, or an organism that consumes only vegetation and/or algae, consumes the producer.

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The carnivore consumes meat, or other animals such as the herbivore. It's the last.

⇒

⇒

Therefore the answer is
B.
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Question 2: I'm pretty sure that succession as well as regrowth after volcanic eruption (Just look at Mount St. Helens. After 30-35 years after the eruption, nature is
still recovering) happens over time/slowly. I would say global warming [C](?) would be the answer.
Answer:
have curved protofilaments at their plus ends
Explanation:
Microtubules are polymers of tubulin proteins that function as the cytoskeleton of eukaryotic cells. Microtubules are dynamic structures that can grow and shrink at a rapid rate. During this process, tubulin subunits can associate and dissociate at the plus end of the protofilament. Tubulin subunits bind to two GTP molecules, one of which is hydrolyzed to GDP after assembly. When microtubules are unstable, protofilaments curl outwards because GDP-bound tubulin has a weak affinity (thereby curving it) and disassemble. The dynamic stability of microtubules is regulated by a feedback loop: when microtubules shrink, free tubulin concentration increases and microtubules start to grow. As microtubules grow, free tubulin concentration decreases and the rate of GTP-tubulin addition also decreases.
DNA, Chromosomes, Nucleus, Cell, Organism
Explanation:
DNA makes up the Chromosomes, which are stored in the nucleus, which is the brain of the cell, and cells make up organisms.