Question

1. which of the following is not matched correctly? a. carbohydrates- provide short energy; structural part of cell walls b. lipids- provide long term energy; component of cell membranes c. proteins- provide energy needed for protein synthesis d. nucleic acids- stores genetic information; protein synthesis 9. many of the proteins in the human body are enzymes that catalyze chemical reactions. what is the relationship between enzymes and activation energy? enzyme action reactants: glucose + o₂ products: co₂ + h₂o a. when an enzyme catalyzes a reaction, it increases the activation energy of the reaction and speeds it up. b. when an enzyme catalyzes a reaction, it increases the activation energy of the product and speeds it up. c. when an enzyme catalyzes a reaction, it decreases the activation energy of the reaction and speeds it up. d. when an enzyme catalyzes a reaction, it does not affect the activation energy of the reaction. 11. large bodies of water, such as lakes and oceans, do not quickly fluctuate in temperature. what is the reason for this phenomenon? a. water is an acid. b. water is a versatile solvent. c. water acts as a buffer. d. water has a high heat capacity.

Explanation:

• For question 7: Carbohydrates provide short - term energy but are not a structural part of cell walls (cellulose in plants is a polysaccharide but not the general function of all carbohydrates). Lipids provide long - term energy and are components of cell membranes. Proteins are involved in many functions but not directly providing energy for protein synthesis. Nucleic acids store genetic information and are involved in protein synthesis.
• For question 9: Enzymes are biological catalysts that lower the activation energy of a chemical reaction, thus speeding up the reaction rate.
• For question 11: Water has a high heat capacity, which means it can absorb or release a large amount of heat energy without a significant change in temperature. This property helps large bodies of water maintain a relatively stable temperature.

Answer:

1. A. Carbohydrates - provide short energy; structural part of cell walls
2. C. When an enzyme catalyzes a reaction, it decreases the activation energy of the reaction and speeds it up.
3. D. Water has a high heat capacity.