D! The Cell membrane in found in all cells, and it is a single (mono) layer.
2. To focus a microscope using the high power lens you must first in low power center the specimen and make sure it is in focus. Then switch to high power and adjust using the fine adjustment or the smaller knob.
3. It prevents dust from settling on the scope and in the lenses.
Answer:
Epinephrine binds to receptors on some smooth muscles (ex: around arterioles) → Ca++ released from ER → intracellular Ca++ up → stimulates contraction. c. Epinephrine binds to receptors on some smooth muscles (ex: around bronchioles) → phosphorylates protein needed for response to Ca++, preventing response.
The correct answer is B, I know this because none of the other answers are even reasonable. For example-
A is wrong because the size of elephant tusk has not changed over time, elephant tusk just grow...
C is wrong because it makes no sense to hunt elephants with no tusk :/
D is completely wrong because tusk have nothing to do with reproduction, those are two completely separate bodily functions.........
