WorksheetsPractice 1
Total questions: 18
Worksheet time: 9mins
Besides storing genetic information, what is another function of nucleic acids?
regulating homeostasis in cell membranes
directing the synthesis of proteins
Which two macromolecules are the main energy sources for cells?
lipids and carbohydrates
carbohydrates and proteins
Chitin is a polysaccharide found in insect exoskeletons. To which major category of biological molecules does chitin belong?
nucleic acids, because chitin provides the blueprint for insect body plans
carbohydrates, because chitin is used for structural support in the insect’s external skeleton
The table shows the composition, uses, and examples of four molecules. Which option correctly completes the table?
A=fructose and lipids, B=cell control and fuel, C=deoxyribose and ribose, D=nucleotides and myosin
A=DNA or RNA, B=cell fuel and support, C=fatty acids and glycerol, D=hemoglobin and amylase
If liver cells lack amino acids, which macromolecule can't they make?
proteins
nucleic acids
The graph shows how the activity of three enzymes changes with pH. What does the graph show about these enzymes?
Each enzyme works in a certain pH range.
All enzymes work at every pH.
What do these enzymes do?
adjust body temperature for reactions
lower the energy needed for reactions
Why does ice form on the surface of a pond in freezing weather?
Water molecules in ice are less dense than in liquid water.
Water molecules in liquid water are less cohesive than in ice.
Michael wants to test how stomach acid concentration affects the solubility of a pill. Which setup would best answer his question?
Expose several pills to different acid concentrations and measure the remaining surface area of each.
Expose several pills to the same acid concentration and measure the remaining surface area of each.
Students want to find out which detergent removes oil stains best. They stain five cloths with oil and wash each with a different detergent, repeating the test two more times. What step should be part of their plan?
Use separate, identical cloths for each oil stain.
Use a different type of oil for each test.
Researchers studied how exercise affects cholesterol. One group of college students ran daily for six weeks. Another group of senior citizens did water aerobics twice a week for a year. Cholesterol dropped slightly in students but significantly in seniors. What should researchers do next to confirm these results?
Decide that exercise lowers cholesterol more in older people than young adults.
Plan more studies on how exercise duration and intensity affect cholesterol in different ages.
Jen and Ori are testing how sand and water absorb energy. They put water in one beaker and sand in another, heat both on a hot plate, and record the temperature every minute. How could they make their experiment more reliable?
repeated the experiment multiple times to see if they obtained the same results
used another heat source in addition to the hot plate to see if different sources of heat changed the amount of energy absorbed
Water makes up about 60% of the human body. Which property of water allows it to transport molecules and play a vital role in life’s functions?
Water molecules are polar and have the ability to dissolve many organic compounds necessary for life.
The strong hydrogen bonds among the water molecules prevent the molecules from being broken apart as they are transported throughout the body.
A student measured the volume of oxygen released when different amounts of catalase were added to hydrogen peroxide. The results are shown below (in mL):
1 mL catalase: 9 mL
2 mL catalase: 12 mL
3 mL catalase: 14 mL
4 mL catalase: 14 mL
5 mL catalase: 14 mL
Which graph best shows the effect of catalase concentration on the volume of water displaced?
Why is it important for life that water has a high heat capacity?
It lets water dissolve many substances, making it a universal solvent.
It lets water absorb a lot of heat before its temperature rises, helping humans keep a steady body temperature.
What does a metalloproteinase enzyme do?
It regulates a chemical reaction.
It is a reactant in a chemical reaction.
Collagen belongs to which type of macromolecule?
nucleic acids
proteins
Which of the following is true for all the molecules?
They all have carbon.
They all have at least one fatty acid.
