Chapter 2 Set 2
Which of the following are true concerning catalysts? 1. they lower the energy activation requirements for a chemical reaction to occur 2. they become part of the chemical reaction 3. they include enzymes 4. temperature and concentrations of atoms are more effective in speeding up a chemical reaction than catalysts 1 only, 2 only, 3 only , 1 and 3
1 and 3
If an atom gains an electron it becomes a (an) 1. isotope 2. ion 3. cation 4. anion 1 only, 2 only, 3 only, 4 only, 2 and 4
2 and 4
ATP is a compound used by the body to store chemical energy harvested from other metabolic processes, such as the breakdown of nutrients. This energy can be released to fuel other process, such as the synthesis of other molecules. The usual way in which energy is released from ATP is by the hydrolysis of the last phosphate group in a chain of three phosphates. True or False
True
Which is not a property of water? -it is a solvent -it is a lubricant -it participates in catabolic and anabolic reactions -it is a nutrient -it has a high heat capacity
it is a nutrient
Briefly discuss three ways in which DNA and RNA molecules are structurally different from each other.
For the base they have the same except DNA has thymine and RNA has uracil. DNA also is made up of 2 strands, a double helix, while RNA has one strand. Finally, DNA is self replicating while RNA uses DNA as a blueprint.
Biologists and chemists categorize all compounds into two main classes: inorganic compounds and organic compounds. What are two key differences between these two types of compounds? Which is more likely to be a part of complex biological structures?
One key is inorganic compounds lack carbon while organic compounds always contain carbon. Another key difference is organic compounds always have covalent bond while inorganic can either have a covalent or ionic bond. Organic Compounds are more likely to be part of a complex biological structure.
In DNA, a guanine base will form a hydrogen bond with -a ribose sugar -a deoxyribose sugar -a phosphate group -a thymine base -a cytosine base
a cytosine base
Which is not true about pH? -pH is representative of the concentration of hydrogen ions -pH can indicate the acidity or alkalinity of a substance -if the pH of a solution changes from 7 to 6, this -indicates a 10 fold increase hydrogen -pH 7 is the midpoint of the scale and indicates equal amounts of hydrogen and hydroxide ions -a solution with a pH of 9 is acidic
a solution with a pH of 9 is acidic
Ninety-six percent of the body mass is made from: -calcium, phosphorous, oxygen and nitrogen -carbon, hydrogen, carbon dioxide, and nitrogen -carbon, calcium, hydrogen, and nitrogen -carbon, oxygen, hydrogen and nitrogen
carbon, oxygen, hydrogen, and nitrogen
An atom with 2 or more shells can be described as chemically stable if its valence shell contains _ _. one electron, two electrons, four electrons, eight electrons
eight electrons
Water has polar covalent bonds. Which of the following statements is true of water? -the electrons are equally distributed around the oxygen and hydrogen atoms -the nucleus of the hydrogen atoms attracts electrons making the hydrogen end of the molecule negative -the nucleus of the oxygen atom attracts electrons making the oxygen end of the molecule negative -the molecule will have a negative charge around both the oxygen and hydrogen nuclei
the nucleus of the oxygen atom attracts electrons making the oxygen end of the molecule negative
Atoms are neutral because: -the number of protons equals the number of neutrons -the number of electrons equals the number of neutrons -the number of protons equals the number of electrons
the number of protons equals the number of electrons
What distinguishes an atom of one element from an atom of another element? -the number of electrons -the number of protons -the number of neutrons -the atomic mass
-the number of protons
Which of the following is (are) formed from nucleotides? 1. RNA 2. DNA 3. ATP 1 only 2 only 3 only 1 and 2 1, 2, and 3
1,2 and 3
Positively charged particles located in the nucleus of an atom are protons, neutrons, electrons, all of these choices
Protons
When table sugar, sucrose, dissolves in water, the water is the solvent or solute
Solvent
The monomer unit of a protein contains: -a centrally located carbon -an R side chain that gives specificity -an acidic carboxyl group -an amino group -all of these choices
all of these choices
A chemical reaction where the reactants combine to form a more complex product is what type of reaction? anabolic, catabolic, exergonic, exchange reactions none of these choices
anabolic
Negatively charged particles found in shells around the nucleus of a particular atom : -are equal to the number of protons -are equal to the number of neutrons -are equal to the number of protons plus the number of neutrons in the nucleus -are equal to the atomic mass
are equal to the number of protons
The smallest unit of matter that retains the properties and characteristics of an element is a (an) atom, molecule, compound, proton, cation
atom
The bond between sodium and chloride in NaCl involves: -the sharing of valence electrons -the transfer of electrons from one atom to another -the removal of protons from one atom to another -the addition of neutrons form one atom to another
the transfer of electrons from one atom to another
Which is not true about carbohydrates? -they contain carbon, hydrogen and oxygen -they have mostly ionic bonds -they include glycogen and cellulose -their monomer is a simple sugar -they typically contain hydroxyl groups
they have mostly ionic bonds
The body's most concentrated form of chemical energy and calories is : glucose, protein, triglyceride, starch, glycogen
triglyceride