BS 124 Chapter 2
a biomarker test for cancer should ideally be
inexpensive, easy to perform, and specific
glucose, ribose, 6 carbon sugar are examples of
monosaccharides
the opposite of a decomposition reaction is a ___ reaction
synthesis
apricot have a pH of 3.8. therefore, they are ___
acidic
electrolytes that release hydrogen ions in water are
acids
vinegar, grapes, tomatoes and coffee are examples of what
acids
an acid reacting with a base is
an exchange reaction
matter is composed of elements, which are composed of
atoms
in a covalent bond
atoms share a pair of more of electrons
an organic compound always contains
carbon and hydrogen
the atomic weight of an element whose atoms contain 8 protons, 8 electrons, and 8 neutrons is
16
the first electron shell of an atom can hold a maximum of
2 electrons
a decomposition reaction can be symbolized by
ab a+b
the type of organic molecule that can replicate is a
nucleic acid
a triglyceride consists of
3 fatty acids and 1 glycerol
carbon can form ___ covalent bonds
4
the midpoint of the pH scale is pH
7
carbon hydrogen, oxygen, nitrogen: account for more than ___% of the human body weight
95%
a biomarker is
a body chemical associated with a particular disease or exposure to a toxin
the formula h2o refers to
a molecule that contains 2 hydrogen atoms and one oxygen atom
sodium ions and calcium ions are examples of
cations
an example of a biomarker is
cholesterol
exposure to ionizing radiations may
cloud the lens of the eye, cause cancer, interfere with normal growth
nucleic acids are
composed of building blocks called nucleotides
the pH scale measures the
concentration of hydrogen ions in solution
the atoms of different elements have
different atomic numbers
water causes ionically-bonded atoms to
dissociate
___ has the unique ability among types of organic molecules to replicate
dna
stores genetic information, including instructions for enzymes that synthesize fats and carbohydrates
dna
dna and rna differ in that
dna holds genetic informations and rna uses that information to synthesize protein
the parts of an atom that army single negative electrical charges are called ___
electrons
when atoms form chemical bond, the subatomic particles that directly interact are the ___
electrons
a chemical reaction in which parts of different molecules trade positions is an
exchange reaction
t/f. a complex carbohydrate consists of a phosphate group attached to a sugar molecule
false
t/f. a person with alkalosis has a blood pH less that 7.3
false
t/f. a phospholipid differs structurally from triglyceride in that it has three phosphate groups attache to the glycerol molecule rather than three fatty acid chains
false
t/f. a substance that releases hydrogen ions in water is a base
false
t/f. an acid is an electrolyte that relates hydroxide ions in water
false
t/f. an atom with 10 protons and which has lost 2 electrons is electrically neutral
false
t/f. cholesterol, a type of lipid, is composed of 3 fatty acid chains attached to glycerol
false
t/f. glycogen is a complex carbohydrate that we get directly by eating plants
false
t/f. nucleic acids are composed of building blocks called amino acids
false
t/f. proteins encode nucleic acids
false
t/f. radioactive isotopes have stable nuclei
false
t/f. sodium and chloride atoms combine readily because they both lose electrons
false
t/f. the number of protons in an atom of an element always equal the atomic weight
false
when cations and anions meet, they
form ionic bonds
synthesis reactions are particularly important in the body for
growth of body parts
a simple carbohydrate
has a molecular formula of c6h12o6
saturated fats ___ than unsaturated fats
have more single carbon-carbon bonds
the secondary structure of a protein molecule is the result of
hydrogen bonds
proteins denature when
hydrogen bonds break
table sugar breaking down in to glucose and fructose is a ___ reaction
hydrolysis
the isotope most likely to be used to study the thyroid gland is
iodine-131
the type of chemical bond formed when ions with opposite electrical charge attract is an ___ bond
ionic
electrolytes are substances that
ionize in water
in the body, oxygen
is used during cellular respiration.
when forming a bond, an atom that has 3 electrons in its second shell and filled first shell will
lose 3 electrons from its second shell
two or more atoms bonding form a ___
molecule
a water solution that contains equal numbers of hydrogen ions and hydroxide ions is
neutral
the type of subatomic particle that does not have an electrical charge is a
neutron
the atoms of the isotopes of a particular element vary in the number of
neutrons
___ are building blocks of nucleic acids
nucleotides
in an ionic bond
oppositely charged atoms attract
PET imaging follows the emission of
positrons
the amino acid sequence of a protein is its ___ structure
primary
amino acids are building blocks of ___
protein
in phenylketonuria, an individual cannot break down the amino acid phenylalanine. molecules that include phenylalanine build up in the blood, which causes intellectual disability and other symptoms. this inherited disease can be controlled by following a diet that is very low in
protein
an enzyme is a ___.
protein that speeds up chemical reactions without being changed or depleted
the atomic number of an atom equals the number of ___ and the atomic weight equals the ___.
protons; number of protons plus neutrons
atomic radiation is useful for treating cancer because
radiation harms cancer cells more readily than it does most non cancer cells
a person has alkalosis if the blood pH
rises above 7.5
nucleic acids include
rna and dna
bases reacting with acids form ___ and water
salts
glycogen is stored in the liver and
skeletal muscles
the difference in hydrogen ion concentration between solutions with pH 4 and pH 5 is
tenfold
conformation is
the 3D shape of a molecule, such as a protein
the informational content of DNA and RNA is in the nitrogenous bases because
the bases are of several types and therefore can form a code sequence
chemistry deals with
the composition and changes of substances that make up living as well as non- living matter
a complete atom is electrically neutral because
the number of electrons equals the number of protons
isotopes of an element have
the same atomic number but different atomic weights
the parts of a protein that change when it denatures are
the secondary and tertiary structures
a CT scan differs from a conventional x ray image because it is
three dimensional
the ___ uses iodine in a synthesis reaction
thyroid gland
t/f. a base is an electrolyte that releases ions that combine with hydrogen ions
true
t/f. a protein is formed from a sequence of amino acids
true
t/f. a strong acid reaction with a strong base produces a salt
true
t/f. an atom that has gained or lost electrons is called an ion
true
t/f. an electrolyte ionizes in water
true
t/f. chemically inert atoms always have their outermost electron shell full
true
t/f. chemistry is the study of the composition of matter and how matter changes
true
t/f. dna and rna are nucleic acids
true
t/f. the symbol Na+ represents a sodium atom that has lost an electron
true
t/f. water is an example of a compound
true