The answer is d to the question!!!
One: The cell is able to move material in and out of the cell
Two: It helps the cell maintain necessary conditions for life
Answer & Explanation:
Humans have changed the landscape through the construction of residences and other structures, as well as through the development of ski resorts, mines, and roads. Hunting, oil drilling, and other activities have polluted the environment and have threatened wildlife in tundra ecosystems.
<h2><u>Answer:</u></h2>
The correct option is B (in one direction)
<h3><u>Explanation:</u></h3>
The two atrioventricular (AV) valves, the mitral valve (bicuspid valve), and the tricuspid valve, which are between the upper chambers (atria) and the lower chambers (ventricles). The two semilunar (SL) valves, the aortic valve and the aspiratory valve, which are in the conduits leaving the heart.
So the atrioventricular valves enables blood to spill out of the atria to the ventricles. be that as it may, regularly keeps the reverse of blood and opening. ... these valves to open and after that blood goes through from the atria into the ventricles. and afterward when the weight is developing in the ventricles.