Question

1. some bacteria live in hot springs. their cells contain enzymes that function best at temperatures of 70°c or higher. at a temperature of 50°c, how will the enzymes in these bacterial cells most likely be affected? a. the enzymes will be destroyed. b. the enzymes will lose their bond structure and fall apart. c. the enzymes will require less energy to function at 70°c. d. the enzymes will not increase the rate of reactions as much as they would at 70°c. 21. many land plants store energy in starch. when energy is needed, the starch molecules can be broken down quickly. this chemical reaction produces which of the following? a. monosaccharides b. lipids c. amino acids d. dna 22. in red blood cells, the compound carbonic anhydrase increases the rate at which carbon dioxide is converted to bicarbonate ions for transport in the blood. in red blood cells, carbonic anhydrase acts as which of the following? a. an hormone b. an enzyme c. a lipid d. a sugar 23. ovalbumin is a protein found in eggs. which of the following best describes the molecular structure of ovalbumin? a. a group of six carbon atoms joined in a ring. b. a chain of amino acids folded and twisted into a molecule. c. a set of three fatty acids attached to a molecule of glycerol d. a sequence of nitrogen bases attached to a sugar - phosphate backbone. 24. if scientists search other planets for possible life, they are likely to focus on the presence of molecule containing which of the following elements? a. iron b. carbon c. potassium d. sodium

Explanation:

• Question 20: Enzymes have optimal temperature ranges. These bacteria - specific enzymes work best at 70°C or higher. At 50°C, they won't be as effective in increasing reaction rates as at their optimal temperature.
• Question 21: Starch is a polysaccharide. When broken down, it produces monosaccharides.
• Question 22: Carbonic anhydrase increases the rate of a chemical reaction in red - blood cells, which is the function of an enzyme.
• Question 23: Proteins are composed of chains of amino acids that are folded and twisted into a molecule. Ovalbumin is a protein.
• Question 24: Carbon is the basis of organic compounds and is essential for life as we know it. Scientists searching for life on other planets would likely look for carbon - containing molecules.

Answer:

1. D. The enzymes will not increase the rate of reactions as much as they would at 70°C.
2. A. Monosaccharides
3. B. an enzyme
4. B. A chain of amino acids folded and twisted into a molecule.
5. B. carbon