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
#12 is D
9. The answer is d. both a and b. A molecule shaped like a double helix or a spiral staircase is typical of both deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
10. The answer is b. ATP (adenosine triphosphate) is important to living organisms because it stores energy from food to be used by cells.
11. The answer is a. For a chemical reaction to occur, energy must be taken in or given up. Chemical reactions require energy input to proceed.
12. The answer is d. all of the above. An enzyme is not used up when catalyzing a reaction, it lowers the activation energy of a reaction, and it bonds with a substrate molecule at the enzyme's active site.
13. The answer is b. High magnification and good resolution are both needed to make small objects easier to see. These characteristics allow for clear visualization and detail of small objects.
14. The answer is a. Surface area is an important factor in limiting cell growth because the cells may become too large to remove enough wastes. The larger the cell's surface area compared to its volume, the more efficiently it can exchange materials with its environment.
9. The molecule shaped like a spiral staircase (double helix) is typical of deoxyribonucleic acid (DNA). To determine the correct answer, you can recognize the description of the molecule and its shape. The double helix structure is a unique characteristic of DNA, which is made up of two strands of nucleotides twisted together.
10. ATP (adenosine triphosphate) is important to living organisms because it stores energy from food to be used by cells and has two extra sugar groups. To identify the correct answer, you need to understand the function and structure of ATP. ATP is the main energy currency in cells, storing and providing energy for various cellular processes.
11. The correct answer is a. For a chemical reaction to occur, energy must be taken in or given up. This statement accurately describes the relationship between energy and chemical reactions. In a chemical reaction, energy is required for bonds to be broken and formed. The energy needed can either be absorbed or released during the reaction.
12. The correct answer is d. An enzyme is not used up when catalyzing a reaction, it lowers the activation energy of a reaction, and it bonds with a substrate molecule at the enzyme's active site. Enzymes are biological catalysts that speed up chemical reactions in living organisms. They are not consumed during the reaction and can be used repeatedly.
13. The correct answer is b. High magnification and good resolution are both needed to make small objects easier to see. High magnification allows for the object to appear larger, while good resolution ensures that the details of the object are clear and distinguishable. Both factors are important in microscopy to observe and study small objects.
14. The correct answer is a. Surface area is an important factor in limiting cell growth because the cells may become too large to remove enough wastes. As cells grow, their surface area to volume ratio decreases, making it harder for them to effectively exchange materials with their environment. This can restrict the removal of waste products, leading to cellular dysfunction.