Biology: Chapter Two
Potassium, a metal with one electron in the outermost shell, will react with how many chlorine atoms? (Chlorine is a nonmetal with seven electrons in the outermost shell.)
1
If an element has an atomic number of 12, how many electrons are in its outermost shell?
2
One carbon atom can form covalent bonds with up to ________ other atoms to form an organic molecule.
4
The pH of blood is slightly basic. Which of the following would therefore be an expected pH for blood? 4.7 6.4 7.4 13.8 4.6
7.4
Which statement regarding acids and bases is correct? Acids combine with bases to form sugars. Acids combine with bases to form buffers. Acids increase the proportion of hydrogen ions (H+), and bases reduce the proportion of H+. Acids increase the pH, and bases decrease the pH. Acids are harmful, but bases are not harmful.
Acids increase the proportion of hydrogen ions (H+), and bases reduce the proportion of H+.
Which statement regarding acids and bases is correct? Acids increase the proportion of hydrogen ions (H+), and bases reduce the proportion of H+. Acids combine with bases to form buffers. Acids combine with bases to form sugars. Acids are harmful, but bases are not harmful. Acids increase the pH, and bases decrease the pH.
Acids increase the proportion of hydrogen ions (H+), and bases reduce the proportion of H+.
Which of the following is not a function of ATP within the cell? energy currency of the cell synthesis of macromolecules conduction of nerve impulses contraction of muscle cells All of the answer choices are functions of ATP within the cell.
All of the answer choices are functions of ATP within the cell.
______ keep the pH within bormal limits.
Buffers
________ is a polysaccharide that is found in plant cell walls and accounts for their strength.
Cellulose
Which of the following molecules is NOT a compound?
H 2
Which functional groups are associated with a dehydration reaction?
H and OH
Which of the following molecules is NOT a compound? H2 HCl H2O NaOH C6H12O6
H2
Which of the following statements about hydrogen bonding is incorrect? Hydrogen bonds are easily broken. Hydrogen bonding occurs only between water molecules. The structure of a large, complex molecule can be influenced by hydrogen bonding. Hydrogen bonding can occur between different molecules or within the same molecule.
Hydrogen bonding occurs only between water molecules.
Which of the following statements about hydrogen bonding is incorrect? The structure of a large, complex molecule can be influenced by hydrogen bonding. Hydrogen bonding occurs only between water molecules. Hydrogen bonding can occur between different molecules or within the same molecule. Hydrogen bonds are easily broken.
Hydrogen bonding occurs only between water molecules.
Which of the following is not a property of water that results from hydrogen bonding
Ice melts at -100°C.
Which of the following is not a property of water that results from hydrogen bonding? Water has a high surface tension. Water molecules have cohesiveness. Many polar substances dissolve in water. The temperature of water changes very slowly. Ice melts at -100°C.
Ice melts at -100°C.
During the formation of a polymer, two monomers are joined by the removal of
OH and H.
Which of the following statements is NOT true of chemical bonds?
Table salt (NaCl) is covalently bonded
Rain falling in the northeastern U.S. has a pH between 5.0 and 4.0. Normally, rainwater has a pH of about 5.6. Which of the following statements is not correct?
The pH of the rainwater has changed from neutral to acidic.
Determine what would happen to an individual's proteins if they developed a fever of 103 ∘ F for several days.
The proteins would denature due to the increase in body temperature and would become unable to function correctly.
Hydrogen bonding produces which of the following properties of water?
Water is less dense as ice than as liquid water.
Hydrogen bonding produces which of the following properties of water? Water boils at a lower temperature than expected. Water is less dense as ice than as liquid water. Water can be more dense as ice than as liquid water. Water absorbs heat with a large change in temperature. Water releases heat with a large change in temperature.
Water is less dense as ice than as liquid water.
The moon lacks life and varies dramatically in temperature. If we could keep a layer of water spread on the surface of the moon, what effect would it have?
Water would absorb and hold heat and moderate the temperature extremes.
If an element has an atomic number of 15, then
a neutral atom has 15 electrons
A covalent bond is
a sharing of electrons between two atoms.
When two glucose molecules combine they form a disaccharide molecule and
a water molecule.
The backbone of a nucleic acid strand is composed of
alternating pentose sugars and phosphate groups.
Organic molecules
always contain carbon (and usually hydrogen).
Since pure water is neutral in pH, it contains
an equal number of hydrogen ions (H +) and hydroxide ions (OH -).
In water, a weak hydrogen bond occurs between hydrogen in one molecule and
an oxygen atom in a different molecule.
Which of these combinations would be found in a nucleotide? base-sugar-phosphate base-acid-salt adenine-thymine-uracil sugar-protein-fat DNA-RNA-nucleus
base-sugar-phosphate
Which of these combinations would be found in a nucleotide? adenine-thymine-uracil base-acid-salt sugar-protein-fat base-sugar-phosphate DNA-RNA-nucleus
base-sugar-phosphate
Calcium chloride, CaCl 2, is an ionic compound in which
calcium has lost two electrons.
Maltose is classified as a
carbohydrate.
You notice that rain water forms "beads" on your car. This is an example of what property of water?
cohesion
Two molecules of glucose combine to form a disaccharide molecule during a(n) ________ reaction.
dehydration
What type of reaction is necessary to produce a dipeptide from individual amino acids?
dehydration reaction
The final shape of a protein is very important to its function. When proteins undergo an irreversible change in shape called ________ they ________ perform their usual functions.
denaturation/cannot
A long chain of carbon atoms with hydrogen atoms attached, ending in the acidic carboxyl group would be a(n)
fatty acid.
Which nutrient source is the easiest one for humans to break down and form ATP?
glucose
Which type of bond formation is responsible for the properties of water?
hydrogen
Water is a liquid at room temperature. This is due to
hydrogen bonding between water molecules.
The water strider is an insect that skates across the water without sinking. The tips of its feet must be coated with molecules that are
hydrophobic.
If neutral atoms become positive ions, they
lose electrons.
Nucleic acids are polymers of
nucleotides.
What type of bond will connect the amino acids in a protein?
peptide
Which of the following types of lipids is the most abundant constituent of cell membranes?
phospholipid
Which group of lipids will contain a barrier formed by hydrophilic heads that face outwards and hydrophobic tails that face inwards? triglycerides phospholipids steroids trans-fatty acids saturated acids
phospholipids
Glycogen is a
polysaccharide used to store glucose/energy.
The ________ structure of a protein consists of the sequence of the amino acids joined together by peptide bonds.
primary
A genetic mutation can cause a change in the sequence of the 20 amino acids used to build proteins. Such a change is a change to the protein's
primary structure, but this will likely alter higher levels of structure as well.
Enzymes are organic compounds classified as
proteins.
The nucleus of an atom contains
protons and neutrons
Which of the following subatomic particles will be found within the nucleus of the atom? only protons only neutrons electrons and neutrons protons and electrons protons and neutrons
protons and neutrons
Hemoglobin is a protein composed of two pairs of polypeptide chains. What is the highest level of protein structure represented by hemoglobin?
quaternary
The primary function of carbohydrates is
quick fuel and short-term energy storage.
The proposed cause of CJD and kuru in humans, mad cow disease, and scrapie in sheep is a change in a brain protein. Disease victims appear to have a protein that should normally contain alpha helices but instead they have changed into a protein made of beta pleated sheets. The disease appears to spread when the abnormal protein comes into contact with the normal protein, causing it to become deformed. Which level of protein structure is associated with these diseases?
secondary
What type of lipid molecule is characterized by a backbone of four fused rings?
steroid
Which type of lipid molecule is characterized by a backbone of four fused rings?
steroid
Cholesterol is a component of cell membranes and is an example of which type of lipid?
steroids
Potassium hydroxide (KOH) almost completely dissociates in aqueous solution into K + and OH -, which means it is a
strong acid
To produce images of the body in order to help medical professionals examine and diagnose, patients may undergo an MRI scan, a mammogram, or an X-ray (among other procedures). MRI imaging works by
subjecting hydrogen nuclei to fluctuating magnetic fields.
The lower the pH
the more acidic the solution.
How elements interact with each other is dependent on
the number of openings for electrons in the outermost shell.
Isotopes of a given element have
the same number of protons but differ in atomic mass.
When an ionic bond forms, electrons are
transferred from one atom to another.
Polar covalent bonds result from
unequal sharing of electrons in a covalent bond.
Which of the following radiation uses is the one that is most likely to have both beneficial and harmful consequences? using radiation to treat a cancer patient using radiation to sterilize mail radiating fruits and vegetables prior to storage using radiation to sterilize surgical equipment prior to a surgery All of the answer choices will have beneficial and harmful consequences.
using radiation to treat a cancer patient