Deck 2 (MR): Some Basic Chemistry

Question 1

Which of the following statements are true of chemical reactions (Select all that apply)?

A)In a synthesis reaction,bonds are formed.
B)In a decomposition reaction,bonds are broken.
C)The body's chemical reactions take place in water.
D)Synthesis reactions are directly necessary for energy release from food.
E)The ionization of a molecule of sodium chloride is a synthesis reaction.
F)Digestion of food involves decomposition reactions.

Answer 1

A,B,C,F

Question 2

Which of the following statements are true of pH and solutions (Select all that apply)?

A)A solution with a pH of 7 is considered neutral.
B)Only a pH of 8 or higher is alkaline.
C)The entire pH scale ranges from 1 to 15.
D)As the number of H+ ions in a solution increases,so does the pH value.
E)A solution with a pH of 4 is four times as acidic as a solution with a pH of 1.
F)The pH of the blood is important for the chemical reactions that take place in the blood.
G)A body fluid such as gastric juice has the same pH range as blood because both are extracellular fluids.
H)Among the organs that help regulate the pH of the blood are the kidneys.

Answer 2

A,F,H

Question 3

Which of the following statements are true of trace elements (Select all that apply)?

A)Iron is part of the hemoglobin in RBCs.
B)Vitamin B12 contains the mineral copper.
C)The transmission of nerve impulses depends on sodium and potassium.
D)Cobalt is needed for the hormone thyroxine.
E)Phosphorus is part of DNA and RNA.
F)The mineral necessary for blood clotting is iodine.g.The mineral that helps store oxygen in muscle cells is magnesium.
H)Sulfur is part of some proteins.

Answer 3

A,C,E,H

Question 4

Which of the following statements are true of the active site theory of enzyme functioning (Select all that apply)?

A)The shape of the enzyme is important.
B)The shape of the substrate is important.
C)The shape of the active site may be altered by changes in pH.
D)The active site portion of the enzyme is not affected by temperature changes.
E)The active site is a specific sequence of amino acids.
F)Most enzymes are proteins,but a few are lipids.

Question 5

Which of the following statements are true of water and its functions (Select all that apply)?

A)The human body changes temperature slowly because it is 90% water.
B)Excessive sweating may lead to dehydration.
C)Excess body heat may be lost in the evaporation of sweat on the skin surface.
D)The sense of taste depends on the lubricant function of water.
E)Urine is a fluid in which waste products are dissolved.
F)Synovial fluid is mostly water,and is a lubricant in the digestive tract.
G)Water prevents sudden,drastic changes in temperature because of its low heat capacity.
H)The sense of smell depends on the solvent function of water.

Question 6

Which of the following statements are true of elements (Select all that apply)?

A)C,H,and O stand for carbon,hydrogen,and oxygen.
B)Cu and Cl stand for copper and chlorine.
C)Fe and I stand for iron and iodine.
D)N and Na stand for nitrogen and potassium.
E)Ca and K stand for calcium and sodium.
F)Z and M stand for zinc and magnesium.

Question 7

Which of the following statements are true of ions and ionic bonds (Select all that apply)?

A)When an atom loses one electron,it then has a charge of negative 1.
B)A positive ion may be called a cation.
C)A sodium ion will bond with two chloride ions to form a molecule of sodium chloride.
D)A chloride ion is a cation.
E)Ionic bonds may break in an aqueous solution.
F)The ionic bonds of a salt are weak in the solid state.

Question 8

Which of the following statements are true of cell respiration (Select all that apply)?

A)The reacting molecules are CO2 and glucose.
B)All the energy released is in the form of heat.
C)The reacting molecules are glucose and oxygen.
D)The waste products of the process are CO2 and water.
E)Energy is released when glucose is broken down gradually.
F)Energy a cell can use is trapped in molecules of ATP.
G)The water that is produced is exhaled.
H)A molecule of ATP is made from ADP plus a phosphate plus energy.

Question 9

Which of the following statements are true of covalent,hydrogen,or disulfide bonds (Select all that apply)?

A)Covalent bonds are formed when atoms share electrons.
B)Organic molecules such as glucose are held together by covalent bonds.
C)The element carbon only rarely forms covalent bonds.
D)Hydrogen bonds help maintain the three-dimensional shape of proteins.
E)Disulfide bonds help maintain the three-dimensional shape of carbohydrates.
F)Covalent bonds are relatively strong,except in water,where they weaken and tend to break.

Question 10

Which of the following statements are true of the bicarbonate buffer system (Select all that apply)?

A)This buffer system is found in the blood.
B)Buffers are chemicals that can create large changes in pH when needed.
C)A disadvantage of this system is that it works very slowly.
D)The weak acid part of the system is NaHCO3.
E)H2CO3 ionizes to HCO3- and H2.
F)When this buffer system buffers a strong base,water is formed.

Question 11

Which of the following statements are true of the functions of organic molecules (Select all that apply)?

A)True fats are an energy storage molecule.
B)Glycogen forms structural components of cells,such as membranes.
C)Pentose sugars are part of polysaccharides.
D)DNA is the genetic code in chromosomes.
E)Phospholipids are part of cell membranes.
F)Cholesterol is the precursor molecule for a hormone such as insulin.
G)Oligosaccharides form antigens on cell membranes.
H)Cellulose is made of glucose,and is a source of energy.

Question 12

Which of the following statements are true of the structure of organic molecules (Select all that apply)?

A)The subunits of polysaccharides are monosaccharides.
B)Amino acids are the subunits of nucleic acids.
C)Fatty acids are subunits of phospholipids.
D)Glycerol is a subunit of steroids.
E)Glucose is the subunit of glycogen.
F)Nucleotides are large molecules made of DNA or RNA.

Question 13

Which of the following statements are true of water and the body's water compartments (Select all that apply)?

A)Once water is part of plasma,it always remains part of plasma.
B)The spaces between cells contain tissue fluid.
C)Lymph is the name for the fluid in lymphatic vessels.
D)Water in veins is called plasma.
E)Intercellular water is the water within cells.
F)Intracellular water is another name for tissue fluid.