Two atoms share a pair of electrons equally. This means that they are joined by
a nonpolar covalent bond.
The major storage polysaccharide in animals is
RNA and DNA are similar in structure in many ways, but one key difference is that
In RNA, uracil replaces the thymine of DNA.
The beta-pleated sheet is an example of the ____ level of protein structure.
The subunits of DNA and RNA consist of
a pentose sugar, a phosphate group, and a nitrogenous base.
Passive diffusion of water across a semipermeable membrane.
In a DNA molecule:
The two strands are held together by hydrogen bonds between the As of one strand and the Ts of the other, and the Gs of one strand and the Cs of the other.
are derived from a symbiotic relationship between prokaryotic and eukaryotic cells.
Osmosis occurs when:
Water flows across a semipermeable membrane down its concentration gradient.
The inside of a cell usually has a ________ charge compared to the fluid outside it (hint: think about the sodium-potassium pump).
In allosteric regulation of enzyme activity:
The ability of the active site to accept substrates is controlled.
The second law of thermodynamics states that:
There is a continual increase in the entropy of the universe.
Lower the activation energy barrier of chemical reactions.
Which of the following statements is TRUE?
Enzymes lower the activation energy of reactions.
An element is a substance that cannot be broken down into other substances by ordinary chemical means.
When making wine which of the following molecules are excluded to encourage fermentation?
All atoms are electrically neutral, so the number of protons =
the number of electrons.
Atoms with the same atomic number, but different numbers of neutrons are isotopes of
The lowest electron shell holds a maximum of how many electrons.
The number of electrons in the outer shell of an atom is referred to as the
number of valence electrons.
This sharing of electrons is referred to as a _______ chemical bond
A measure of disorder or randomness. The more randomly arranged a collection of matter is the greater its entrophy.
Study of the energy transformations that occur in a collection of matter
1st Law of Thermodynamics
The energy of the universe is constant. Energy cannot be created or destroyed
2nd Law of Thermodynamics
every energy transfer or transformation increases the entrophy of the universe.