biology chapter 2 mastery
What is the maximum number of singe covalent bonds a carbon atom can form with other elements
4
How many neutrons are in a typical oxygen atom?
8
The typical oxygen atom is described in the periodic table by the accompanying box. How many protons are in a typical oxygen atom?
8
While the maximum number of electrons required to fill the outermost shell of an atom varies depending on the size of the atom, almost all of the smaller atoms (atomic numbers 2-20) are considered stable (nonreactive) when they contain ________ electron(s) in the outermost shell.
8
oxygen atom
8 protons, 8 neutrons, 8 electrons
What is the basic structure of typical dietary fats?
A glycerol head and up to three fatty acid tails
Element
A substance that cannot be broken down into simpler substances
What is a trace element?
An element that is required in miniscule amounts for life
Identify the reactants in the following chemical reaction: C10H8 + 12 O2 → 10 CO2 + 4 H2O
C10H8 and 12 O2
What are the four classes of large organic molecules important to life on Earth?
Carbohydrates, proteins, lipids, and nucleic acids
Why is one side of a single water molecule partially negative while the other side is partially positive?
Electron pairs are unevenly shared between the oxygen atom and the two hydrogen atoms.
Part complete Evaluate this statement: Cholesterol is a type of lipid, and thus all cholesterol lipids are bad for human health.
False, because some types cholesterol increase heart disease, but other types are necessary, especially in the plasma membrane.
Which of the following represents a simple sugar (also called monosaccharides)?
Glucose
Which of the following is not made from long chains of glucose?
Monosaccharides
what is the most common element in your body
Oxygen
Water "beads up" on synthetic fabric like polyester but binds to cotton. What is the most likely explanation for this?
Polyester is nonpolar, whereas cotton is polar.
What is another name for the polymers of carbohydrates?
Polysaccharides
Protons
Positively charged particles
A needle can be made to "float" on the surface tension of water. What causes this surface tension to form?
The cohesion of water molecules to each other
Select the most complete explanation of what the pH scale actually measures.
The concentration of hydrogen ions in a solution
What might happen if a protein has a change in one amino acid?
The protein can no longer function properly. The amino acid chain folds incorrectly. The protein has a new shape.
What will be accomplished by lowering the activation energy of a reaction?
The reaction will proceed more quickly.
To a large extent, a protein's function is dependent upon its shape. What determines a protein's shape?
The sequence of amino acids
What are the ecological consequences of acidification of rain and oceans?
They damage the health of ecosystems.
Something with a pH of 5 would be
acidic
What are the monomers of proteins?
amino acids
How do buffers minimize change in the pH of biological systems?
by absorbing H+ ions when there is an excess and by donating H+ ions when there is a shortage
Which is not one of the four atoms that make up the bulk of living organisms?
calcium
Based on the suffix, a molecule of "maltose" is most likely what type of macromolecule?
carbohydrates
which of the following classes of large organic molecules includes table sugar
carbohydrates
Organic compounds are distinguished by molecules that contain ________ bonded to other elements.
carbon
Which of the following is a polysaccharide?
cellulose
the chemical name for table salt is sodium chloride, or simply NaCl. what type of chemical is NaCl
compound
The bond in which bonded atoms share electrons is called a
covalent bond
The building of a large organic molecule from small subunits involves multiple
dehydration synthesis reactions
Proteins are diverse molecules that perform a wide variety of functions. Which of the following is not a typical function of proteins?
energy storage
Organic molecules that end in the suffix "-ase" often function as ________ molecules.
enzymatic
Water is the least dense when it
freezes
The 2+ in Cu2+ tells us that this atom _
has two more protons than electrons
Individual water molecules are held to one another by relatively weak ________ bonds.
hydrogen
Carbohydrates, proteins, lipids, and nucleic acids
hydrolysis reaction
All lipids are
hydrophobic
If the number of protons in an atom does not match the number of electrons, the atom is specifically called
ion
in an atom, the number of neutrons determines most specifically the
isotope
What is the sum total of all the chemical reactions that take place in your body called?
metabolism
Electron
negatively charged particle
Neutron
no charge
What kind of bond joins amino acids together to form a protein?
peptide bond
Enzymes are a type of
protein
During a chemical reaction, atoms are
rearranged
Which would have the highest concentration of C-H bonds?
saturated fat
Identify the part of the atom that most determines the chemical properties of the atom.
the number of electrons
The majority of the elements essential to life are found in what part of the periodic table?
the top third
Oil hydrogenation can produce a product, such as vegetable shortening or margarine, that is spreadable at room temperature because of an unusual bond that does not occur naturally. What is the name of this category of lipid?
trans fat
Which of the following dietary fats is considered to be the least healthy?
trans fat