Answer:
The correct option is B. Activation energy
Explanation:
The activation energy is usually used to designate the minimum energy necessary for a given chemical reaction to occur, that is, the basic requirement for the reaction to proceed.
For a reaction to occur between two molecules, they must collide in the correct orientation and have a minimum amount of energy. As the molecules approach, their electron clouds are rejected. This requires energy (activation energy) and comes from the heat of the system, that, is, from translational, vibrational energy, etc of each molecule. If the energy is sufficient, the repulsion is overcome and the molecules are close enough for a rearrangement of the bonds of the molecules.
The concept of Activation energy was introduced by Arrhenius in 1889. Arrhenius suggested that molecules must prossess a minimum amount of energy to react. That energy comes from the kinetic energy of the clliding molecules. Kinetic energy serves to cause reactions, but if the molecules move very slowly, the molecules will only bounce when they collide with other molecules and the reaction does not happen. In order for the molecules to react, they must have a total kinetic energy that is equal to or greater than a certain minimum value of energy called activation energy.
Answer:
The correct answer is c) The first statement is true; the second is false.
Explanation:
To be able to perform its role, a hormone must bind a specific receptor in its target cell. The receptor can be located inside the cell (in cytosol) or in the surface of the cell (transmembrane receptor). By regulating the expression of the receptor, the target cell regulates the hormonal activity.
The number of hormone receptors in a cell is not constant, it can vary depending on sereral factors, such as the age of the organisms, the effect of several drugs, mutations or diseases.
Explanation:
The glow-worm begins its life in the autumn as a pale yellow egg. The freshly laid egg is extremely fragile but within a day its surface has hardened into a shell.
Well, pollution is probably the main reason, but i think all of them are reasons why animals are dying off, if there isn't any choice for all of them, then your best bet would be to do a, pollution.