Ch.2 Anatomy
Which of the following statements about chemical bonds is true?
Covalent bonds are stronger than ionic bonds.
The characteristic that gives an element its distinctive properties is its number of
H2
Uracil
all of the above
When an atom donates an electron to another atom, it becomes
an ion
The smallest unit of an element that still retains the distinctive behavior of that element is an
atom
AB→A+B is a general notation for a(n) ________ reaction.
decomposition
In DNA, nucleotide bonding forms a compound with a characteristic shape known as a(n) ________.
double helix
A phospholipid
has both polar and nonpolar regions
Which of the following combinations of atoms is most likely to result in a chemical reaction?
hydrogen and hydrogen
A pentose sugar is a part of the monomer used to build which type of macromolecule?
nucleic acids
CH4 is methane. This compound is
organic
Together, just four elements make up more than 95 percent of the body's mass. These include
oxygen, carbon, hydrogen, and nitrogen
A molecule of ammonia contains one atom of nitrogen and three atoms of hydrogen. These are linked with
polar covalent bonds
The energy stored in a foot of snow on a steep roof is
potential energy
A substance dissociates into K+ and Cl- in solution. The substance is a(n) ________
salt
The ability of an enzyme's active sites to bind only substrates of compatible shape and charge is known as ________.
specificity
Nitrogen has an atomic number of seven. How many electron shells does it likely have?
two
Which of the following is a functional group that is part of a building block of proteins?
amino
What organic compound do brain cells primarily rely on for fuel?
glucose
On the periodic table of the elements, mercury (Hg) has an atomic number of 80 and a mass number of 200.59. It has seven stable isotopes. The most abundant of these probably have
more than 80 neutrons each
The characteristic that gives an element its distinctive properties is its number of
protons
Chewing a bite of bread mixes it with saliva and facilitates its chemical breakdown. This is most likely due to the fact that
saliva contains enzymes
A substance formed of crystals of equal numbers of cations and anions held together by ionic bonds is called a(n)
salt
Jenny mixes up a batch of pancake batter, then stirs in some chocolate chips. As she is waiting for the first few pancakes to cook, she notices the chocolate chips sinking to the bottom of the clear glass mixing bowl. The chocolate-chip batter is an example of a
suspension