Answer:
cutting down trees over a large area
The answer is b. An animal that relies on the digestive tract for digestion breaks down food via extracellular digestion. The digestive tract uses mechanical and chemical processes to digest the food. Extracellular digestion is a type of digestion that happens in an opening as part of a digestive system where the nutrients produced from digestion is transferred to the blood or other body fluids. The digestive tract serve as the opening.
Answer:
Genetic variation
Explanation:
It could lead to natural selection, but natural selection isn't the cause. Many years down the road you could see a particular variation having a higher population, which is the result of natural selection/survival of the fittest via better camouflaging from predators.
Explanation:
Cells in each germ layer differentiate into tissues and embryonic organs The ectoderm gives rise to the nervous system and the epidermis, among other tissues
