Module 1.2 Flashcards
the aqueous environment
Water
emphasized that for life to exist at all , the environment must first be suitable and that leads to water.
Henderson
Water moderates air temperature __________ from air that is warmer and _____________ to air that is cooler
by absorbing heat
releasing the stored heat
It relates to which heat must be ______ in order to break hydrogen bonds.
heat is _____ when hydrogen bonds formed.
absorbed;
released
This property of water also helps warm the air when it is nighttime and tends to stabilize the ocean temperature, creating a favorable environment for marine life.
because of this property, the water that covers most of the Earth keeps temperature fluctuations on land and in water within limits that permit life
Moderation of Temperature by Water
As a liquid evaporates, the surface of the liquid that remains behind cools down.
Evaporative Cooling of Water
This _________ occurs because the “hottest” molecules, those with the greatest kinetic energy, are the most likely to leave as a gas
evaporative cooling of water
contributes to the stability of temperature in lakes and ponds and also provides a mechanism that prevents terrestrial organisms from overheating.
evaporative cooling of water
helps keep the tissue in the leaves from becoming too warm in the sunlight.
also helps human to prevent overheating on a hot day or when excess heat is generated by strenuous activity by evaporation of sweat from human skin dissipating body heat.
evaporation of water
what property?
the ability of ice to float due to its ________ is an important factor in the sustainability of the environment since if ice sank, then eventually all bodies of water would freeze solid, making life to be impossible
evaporative cooling of water;
lower density
Water acts as _______on a mixture of two or more substances which is called a _________.
solvent; solution
The solvent is then involved in the dissolving of ions which contributes to processes happening in the body such as the formation of the __________,
a sphere of water molecules around each dissolved ion.
hydration shell,
two families of nitrogenous bases:
pyrimidine
purine
members of pyrimidine (3)
cytosine, thymine, uracil
purines (2)
adenine guanine
complementary base pairings
A-T (DNA) / A-U (RNA)
G-C
In terms of sugar, in DNA, it is called _____and RNA has the sugar, ____.
deoxyribose
ribose
Nearly every dynamic function of a living being depends on ________.
proteins
Proteins account for more than ____of the dry mass of most cells, and they are instrumental in almost everything organisms do
50%
Kinds of interactions in tertiary structure: (3)
hydrophobic
hydrogen and ionic bonds
disulfide bridges
interaction caused by the exclusion of nonpolar substances by the water molecules
hydrophobic interaction
_______ bonds are between polar side chains and ____ bonds are between positively and negatively charged side chains
Hydrogen bonds; ionic bonds
These further reinforce the shape of a protein.
Disulfide bridges
Disulfide bridges are formed when two _____monomers which have ____ groups on their side chains are brought closer together by the folding of protein.
cysteine;
sulfhydryl groups (-SH)
is an alcohol; each of its three carbons bear a hydroxyl group
glycerol
has a long carbon skeleton, having a carbon at one end which is a part of the carboxyl group.
fatty acid
In making a fat or triacylglycerol, three fatty acid molecules are each joined to glycerol by an _____ linkage, a bond between a hydroxyl group and carboxyl group.
ester
The major function of fats is ________. The hydrocarbon chains are similar to gasoline molecules and rich in energy. They also cushion such vital organs as the kidneys, and layer beneath the skin insulates the body.
energy storage
Simple – sugar molecules not only function as a major ____ for cellular work, but their ________ also serve as raw material for the synthesis of small organic molecules such as amino acids.
fuel; carbon skeletons
plants store ______;
animals store _____;
starch,
glycogen
which is the major component of the tough walls that enclose plant cells, and is also the major constituent of paper and the only component of cotton.
cellulose
is used by arthropods for their exoskeleton (hard case protecting the soft parts of the body)
chitin
