BS 161 Chapter 2 questions with verified answers
A ________ bond results when two atoms share electrons Ans✓✓✓ covalent
A fatty acid is a: Ans✓✓✓ A fatty acid is a long chain of carbon atoms attached to
a carboxyl group (-COOH) at one end
acidic Ans✓✓✓ When the concentration of protons is higher than that of
hydroxide ions, the pH is lower than 7 and the solution is acidic.
An acid can therefore be described as a molecule that releases a proton (H+)
Aldose vs ketose Ans✓✓✓ monosaccharides with a aldehyde group or ketone
group
In both types of monosaccharides, the other carbons each carry one hydroxyl (-
OH) group and one hydrogen (H) atom.
alpha carbon Ans✓✓✓ The central carbon atom of each amino acid.
amino acids and peptide bonds Ans✓✓✓ peptide bond: A covalent bond that
links the carbon atom in the carboxyl group of one amino acid to the nitrogen
atom in the amino group of another amino acid.
amino group Ans✓✓✓ NH2; a nitrogen atom bonded to two hydrogen atoms,
covalently linked to the central carbon atom of an amino acid.
,Approximate proportions by dry mass of chemical elements found in human cells.
Ans✓✓✓
atom Ans✓✓✓ the basic unit of matter
Base pairing results from _________ bonding b/w the bases Ans✓✓✓ hydrogen
Bases Ans✓✓✓ built from nitrogen-containing rings and are of two types
(pyrimidine or purine)
basic Ans✓✓✓ When the concentration of protons is lower than that of
hydroxide ions, the pH is higher than 7 and the solution is basic.
a base is a molecule that accepts a proton in aqueous solution.
because many functional groups are polar, they are also ________. Ans✓✓✓
Because many functional groups are polar, otherwise nonpolar molecules
containing these groups become polar and so become soluble in the cell's
aqueous environment. In other words, they disperse in solution throughout the
cell. Moreover, *because many functional groups are polar, they are also
reactive.*
Because of van der Waals forces, the melting points of fatty acids depend on their
________ and _____________. Ans✓✓✓ Because of van der Waals forces, the
melting points of fatty acids depend on their length and level of saturation.
, Building of macromolecules Ans✓✓✓ rearranging the building blocks that make
up macromolecules provides an important way to make a large number of diverse
macromolecules whose functions differ from one to the next.
carbohydrates can be made up of the same sugars or different sugars Ans✓✓✓
Some complex carbohydrates are composed of a single type of monosaccharide,
while others are a mix of different kinds of monosaccharide. Starch, for example,
is a sugar storage molecule in plants composed completely of glucose molecules,
whereas pectin, a component of the cell wall, contains up to five different
monosaccharides.
carbohydrates Ans✓✓✓ An organic molecule containing C, H, and O atoms that
provides a source of energy for metabolism and that forms the starting point for
the synthesis of all other organic molecules.
make up the cell wall in bacteria, plants, and algae.
carbohydrates such as starch are polymers of _____________ Ans✓✓✓ simple
*sugars*: The simplest carbohydrate molecule; also called a saccharide.
Carbon chains Ans✓✓✓ carbon atoms can link with each other by covalent bonds
to form long chains. These chains can be branched, or two carbons at the ends of
the chain or within the chain can link to form a ring.
Carbon Ans✓✓✓ Human life, and all life as we know it, is based on carbon.
Carbon has the ability to combine with many other elements to form a wide
variety of molecules, each specialized for the functions it carries out in the cell.
A ________ bond results when two atoms share electrons Ans✓✓✓ covalent
A fatty acid is a: Ans✓✓✓ A fatty acid is a long chain of carbon atoms attached to
a carboxyl group (-COOH) at one end
acidic Ans✓✓✓ When the concentration of protons is higher than that of
hydroxide ions, the pH is lower than 7 and the solution is acidic.
An acid can therefore be described as a molecule that releases a proton (H+)
Aldose vs ketose Ans✓✓✓ monosaccharides with a aldehyde group or ketone
group
In both types of monosaccharides, the other carbons each carry one hydroxyl (-
OH) group and one hydrogen (H) atom.
alpha carbon Ans✓✓✓ The central carbon atom of each amino acid.
amino acids and peptide bonds Ans✓✓✓ peptide bond: A covalent bond that
links the carbon atom in the carboxyl group of one amino acid to the nitrogen
atom in the amino group of another amino acid.
amino group Ans✓✓✓ NH2; a nitrogen atom bonded to two hydrogen atoms,
covalently linked to the central carbon atom of an amino acid.
,Approximate proportions by dry mass of chemical elements found in human cells.
Ans✓✓✓
atom Ans✓✓✓ the basic unit of matter
Base pairing results from _________ bonding b/w the bases Ans✓✓✓ hydrogen
Bases Ans✓✓✓ built from nitrogen-containing rings and are of two types
(pyrimidine or purine)
basic Ans✓✓✓ When the concentration of protons is lower than that of
hydroxide ions, the pH is higher than 7 and the solution is basic.
a base is a molecule that accepts a proton in aqueous solution.
because many functional groups are polar, they are also ________. Ans✓✓✓
Because many functional groups are polar, otherwise nonpolar molecules
containing these groups become polar and so become soluble in the cell's
aqueous environment. In other words, they disperse in solution throughout the
cell. Moreover, *because many functional groups are polar, they are also
reactive.*
Because of van der Waals forces, the melting points of fatty acids depend on their
________ and _____________. Ans✓✓✓ Because of van der Waals forces, the
melting points of fatty acids depend on their length and level of saturation.
, Building of macromolecules Ans✓✓✓ rearranging the building blocks that make
up macromolecules provides an important way to make a large number of diverse
macromolecules whose functions differ from one to the next.
carbohydrates can be made up of the same sugars or different sugars Ans✓✓✓
Some complex carbohydrates are composed of a single type of monosaccharide,
while others are a mix of different kinds of monosaccharide. Starch, for example,
is a sugar storage molecule in plants composed completely of glucose molecules,
whereas pectin, a component of the cell wall, contains up to five different
monosaccharides.
carbohydrates Ans✓✓✓ An organic molecule containing C, H, and O atoms that
provides a source of energy for metabolism and that forms the starting point for
the synthesis of all other organic molecules.
make up the cell wall in bacteria, plants, and algae.
carbohydrates such as starch are polymers of _____________ Ans✓✓✓ simple
*sugars*: The simplest carbohydrate molecule; also called a saccharide.
Carbon chains Ans✓✓✓ carbon atoms can link with each other by covalent bonds
to form long chains. These chains can be branched, or two carbons at the ends of
the chain or within the chain can link to form a ring.
Carbon Ans✓✓✓ Human life, and all life as we know it, is based on carbon.
Carbon has the ability to combine with many other elements to form a wide
variety of molecules, each specialized for the functions it carries out in the cell.
