Because they change over time
In active transport particles move by making use of energy in the form of ATP.
<u>Explanation:</u>
Unlike in passive transport particles have to move against the concentration gradient in active transport. Thus particles require energy to do so and this energy is in the form of ATP. Osmosis and simple diffusion are examples of passive transport where substances move from a region of high concentration to a region of low concentration.
This movement is down the concentration gradient. In active transport particles move from a region of low concentration to a region of high concentration which is against the concentration gradient. Active transport is of two types.
In the first type called primary active transport energy is directly used in the form of ATP. In the second type called secondary active transport an electrochemical gradient created by ATP is used to facilitate the transport.
Answer;
-are mirror images of one another.
Thalidomide and l-dopa, shown below, are examples of pharmaceutical drugs that occur as enantiomers, or molecules that are mirror images of one another
Explanation;
-Enantiomers are chiral molecules that are mirror images of one another. Furthermore, the molecules are non-superimposable on one another. This means that the molecules cannot be placed on top of one another and give the same molecule. Chiral molecules with one or more stereocenters can be enantiomers.
Enantiomers have identical chemical and physical properties in an achiral environment. They rotate the direction of plane polarized light to equal, but opposite angles and interact with other chiral molecules differently.
The best answer to the question above would be the first statement. Cardiorespiratory endurance affects physical fitness in such a way that it increases the efficiency with which the body delivers oxygen and nutrients to its cells.
