Answer:
Substances can move from areas of low concentration to high concentration.
Explanation:
For the first one, substances CAN move in and out of cells in an active transport.
As for the second one, active transports do require energy. That is what makes them "active" and sets them apart from <em>passive transports</em> which don't require energy.
Lastly, substances can move across a membrane regardless of if they are water soluble (such as lipids, or fats that the cell does not use. Think of it as a way for the cell to eat, drink, and defecate or remove waste.)
Answer: Erythropoiesis is the process which produces red blood cells (erythrocytes). It is stimulated by decreasing oxygen in circulation detected by the kidney which then secrete erythropoietin that proliferate and differentiate red blood precursors & produce red blood cells.
Explanation: The use of erythropoietin to boost red blood cells is called blood doping. The more red blood cells are present in the body, the more the energy expenditure and the slower you will burn calories during physical activities.
<u>Answer:</u>
<em>The true statement concerning complex multi-cellular organism is Bulk transport systems move substances faster than simple diffusion.</em>
<u>Explanation:</u>
<em>Bulk transport</em> is the mechanism that is used by the cells to transport the large quantity of small and tiny molecules and particles. Bulk transport works on the <em>mechanism of pressure gradient and single diffusion</em> is based on the concentration gradient.
The<em> transportation on single diffusion</em> is due to random motion of molecules but in bulk transport the solute and water is moved <em>together and in a faster pace. </em>
I believe the correct answer is B. Nephridia are excretory organs. They are organs found in invertebrate animals that are present in pairs and are responsible for performing functions that are similar to the kidney of a vertebrate. They excrete wastes from metabolic processes.
answer is D ( totipotent cells can differentiate into more types of cells )
