The substances that protect against oxidative stress and the resultant tissue damage at the cellular level is, option B. Antioxidants. Oxidation can cause imbalance in the body. Antioxidants are used to counteract the damage produced by free radicals. Good natural sources of antioxidants include fruits and vegetables.
I believe a valley or mountain, but I am not 100 percent sure.
An increase in A produces and increase in X
This is a positive feed back mechanism. This mechanism enhance or amplify changes. This tends to alter the balance away from equilibrium because one hormone will increase the release of the other hormone. An example of this is the child birth. During labor, oxytocin is released to increase the uterine contraction the release of oxytoocin will be induced by the contractions of uterus. This will go on until the child was born. Just remember positive feedback enhance the original stimulus.
When the energy from the Sun hits a chloroplast and the chlorophyll molecules, light energy is converted into the chemical energy. Plants use water, carbon dioxide, and sunlight to produce the free energy stored in ATP and NADPH through a process called photosynthesis.
