A)Antibiotics can always be used to treat bacterial infections.
Answer:
Plus end and kinesin.
Explanation:
Three important cytoskeleton components are microtubules, microfilaments and intermediate filaments. Microtubules are the polymer of tubulin and plays an important role in the movement of cell organelles and its structure.
Microtubules shows the process of polymerization and depolymerization at different ends. The plus end shows the polymerization and minus end shows the depolymerization process. The kinesin protein is required for the process of polymerization.
Thus, the correct answer is option (D).
Biosphere. Bio means life, and Biosphere means ALL life on earth.
Answer:
Option A, oxygen in the atmosphere
Explanation:
The highest level of oxygen reached during this phase of the geological cycle of earth. The oxygen level in Carboniferous period accounted for 35% as compared to 21% of oxygen in the atmosphere in present time.
Due to high oxygen content, the giant and wide varieties of terrestrial animal and plant species evolved. For example – size of insects and carwlies increased, plant became extremely giant, increase in number of tree ferns etc.
