A compound isolated from a biological source is subjected to chemical analysis. It contains carbon and oxygen in roughly equal amounts and hydrogen in an amount that is almost twice that of carbon. This compound does not take up iodine stain very well, indicating that its structure is densely packed and resistant to large molecules binding to it through non covalent interactions. What is the likely identity of this compound
Based on information shown in the table, which triglyceride would be expected to have the lowest melting point?
A triglyceride that contains one linoleic and two oleic fatty acids bonded to each glycerol molecule
What is a biological role of both carbohydrates and lipids?
Which linkages in starch and triglycerides result from condensation reactions?
Glycosidic bonds in starch and ester bonds in triglycerides
Table salt, NaCl, is neutral. When dissolved in water, NaCl
dissociates to form Na+ and Cl- ions that interact with water molecules
Phospholipids differ from triglycerides in that phospholipids
The reactivity of an atom arises primarily from the
existence of unpaired electrons in the outermost shell.
is related to the disorder or randomness of a system.
The “building blocks” of polysaccharides are _______, and these blocks are covalently linked together by _______.
monosaccharides; glycosidic linkages
The synthesis of complex molecules _______ energy, whereas their degradation _______ energy. This synthesis occurs with _______ in entropy.
requires; releases; a decrease
A reaction that releases free energy
Which statement best describes the difference between an element and a molecule?
An element is composed of only one kind of atom; molecules can be composed of more than one kind of atom.
An atom that contains ten protons and ten electrons is likely to
be chemically inert (stable)
Covalent bond formation depends on the ability of atoms to
share electrons with other atoms
Which statement about starch is true?
Oils and fats
Which type of bonds or interactions between atoms is the strongest?
Which statement would receive the worst grade in a biology exam covering the first and second laws of thermodynamics?
the total energy of a system is available to do work
Which biological molecule is smallest due to being a subunit rather than a macromolecule?
Water is essential to life. Which property of water affect(s) life less than the others?
Which molecular structure is incorrect?
For a covalent bond to be polar, the two atoms that form the bond must have
Oils melt at a lower temperature than fats because
fats contain more saturated fatty acids than oils
Fatty acids are