Question

you will have two attempts to complete this homework and the highest score will be kept.
question 1
what is the ultimate source of energy for almost all living organisms?
glucose
lipids
oxygen
the sun
question 2
in order for a cell to maintain a high degree of order, it must constantly ____?
use energy
increase energy
release energy
produce energy
question 3
suppose the free energy of the reactants is greater than the free energy of the products. such a reaction is referred to as a(n) ____.
exergonic reaction
endergonic reaction
activation reaction
entropic reaction

Explanation:

• Question 1: Plants use sunlight for photosynthesis to make food (glucose). Other organisms either eat plants or plant - eating organisms. So, the sun is the ultimate energy source.
• Question 2: According to the second law of thermodynamics, the entropy (disorder) of the universe tends to increase. For a cell to maintain order (low entropy), it must use energy (from processes like ATP hydrolysis) to counteract the natural tendency towards disorder.
• Question 3: In an exergonic reaction, the free energy of reactants (\(G_{reactants}\)) is greater than the free energy of products (\(G_{products}\)), i.e., \(\Delta G=G_{products}-G_{reactants}<0\). Energy is released in such reactions.

Answer:

• Question 1: The sun
• Question 2: use energy
• Question 3: Exergonic reaction