9. a molecule shaped like a spiral staircase (double helix) is a typical of
a. deoxyribonucleic acid
b. ribonucleic acid
c. carbohydrates
d. both a and b
D?
10. ATP is important to living organisms because it
a. stores hereditary information
b. stores energy from food to be used by cells
c. has two extra sugar groups
d. both b and c
D?
11. Which of the following is true about the relationship between energy and chemical reactions?
a. For a chemical reaction to occur, energy must be taken in or given up
b. Energy input is required to carry out a chemical reaction
c. Chemical bonds are always broken by energy absorption in a chemical reaction
d. Energy-absorbing reactions don't occur in chemical reactions
I know it's not d but I'm not sure which one it is...
12. An enzyme
a. is not used up when catalyzing a reaction
b. lowers the activation energy of a reaction
c. bonds with a substrate molecule at the enzyme's active site
d. all of the aboce
D?
13. High magnification and good resolution
a. are different names for the same thing
b. are both needed to make small objects easier to see
c. make the object itself larger
d. both a and b
B?
14. Surface area is an important factor in limiting cell growth because
a. the cells may become too large to remove enough wastes
b. materials cannot enter the cell if it is too large
c. the cell can burst if the membrane becomes too large
d. waste products cannot leave the cell if it is too small
Not sure...
Thanks
-MC
9. RNA is usually single stranded.
10. What extra sugar groups is in ATP?
11. c is the best answer,
12 correct
13 correct
14 Cells take in food, and excrete waste products. If cells are very large, waste materials in the center will never get to the outside to be transported out, and food intake, and the amount of food needed cannot be taken in.
So, 10 is just B and 14 A?
Thanks
-MC
9. The molecule shaped like a spiral staircase (double helix) is typical of both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). This means that the correct answer is option (d) "both a and b."
To arrive at this answer, we can first eliminate options (c) carbohydrates because carbohydrates do not have a double helix structure. Next, we compare options (a) and (b) - DNA and RNA. DNA is known for its double helix structure, while RNA has a single helix structure. Therefore, the molecule shaped like a spiral staircase is unique to DNA and not RNA. Since the question states that it is typical of both DNA and RNA, the correct answer is (d) "both a and b."
10. ATP (adenosine triphosphate) is important to living organisms because it stores energy from food to be used by cells, and it also contains high-energy phosphate bonds. This means that the correct answer is option (d) "both b and c."
To arrive at this answer, we first eliminate options (a) and (c) as they do not accurately describe the function of ATP. Option (a) states that ATP stores hereditary information, which is not true. Hereditary information is stored in DNA. Option (c) states that ATP has two extra sugar groups, which is incorrect. ATP consists of adenosine and three phosphate groups.
Next, we compare options (b) and (d). Option (b) correctly states that ATP stores energy from food to be used by cells. Option (d) states both option (b) and option (c). Since option (c) is incorrect, we can conclude that the correct answer is option (d) "both b and c."
11. The correct answer is option (a) "For a chemical reaction to occur, energy must be taken in or given up."
To determine the correct answer, we can analyze the relationship between energy and chemical reactions. Energy is required for chemical reactions to occur, as bonds need to be broken and formed. This means that energy must be taken in or given up. Option (a) accurately describes this relationship.
Option (b) incorrectly suggests that energy input is required to carry out a chemical reaction. While energy is required, this answer choice does not encompass the entire relationship. Option (c) and (d) are both incorrect statements about energy and chemical reactions.
12. The correct answer is option (d) "all of the above."
To determine the correct answer, we can analyze the properties and functions of enzymes. An enzyme is a biological catalyst that facilitates chemical reactions without being consumed itself. This means that enzymes are not used up when catalyzing a reaction (option a). Enzymes also lower the activation energy of a reaction, making it easier for the reaction to occur (option b). Additionally, enzymes bond with substrate molecules at their active site to facilitate the reaction (option c). Since all three statements accurately describe enzymes, the correct answer is option (d) "all of the above."
13. The correct answer is option (b) "are both needed to make small objects easier to see."
To determine the correct answer, we need to understand the terms "high magnification" and "good resolution." High magnification refers to the ability to magnify an object to make it appear larger, while good resolution refers to the ability to distinguish fine details of the object. Both high magnification and good resolution are needed to make small objects easier to see. Therefore, the correct answer is option (b) "are both needed to make small objects easier to see."
14. The correct answer is option (a) "the cells may become too large to remove enough wastes."
To determine the correct answer, we need to understand the concept of surface area and cell growth limitations. As cells grow larger, their volume increases faster than their surface area. This creates a problem because the surface area of the cell's membrane is necessary for exchanging nutrients and wastes with the environment. If the cell becomes too large, it may struggle to remove enough wastes through its limited surface area. Therefore, option (a) is the correct answer.