In general, which of the following can human cells do?
1. Protect themselves
2. Regulate life processes
3. Reproduce
1 and 2 only
1 and 3 only
2 and 3 only
1, 2, and 3
1, 2, and 3
Inorganic materials are compounds that __________ carbon.
contain only very small amounts of
contain moderate amounts of
contain large amounts of
do not contain
do not contain
Antibodies are protein molecules produced by specialized cells in the bone marrow called:
B lymphocytes
R lymphocytes
megakaryocytes
oocytes
B lymphocytes
The much smaller structures that make up nucleic acids are called:
carbohydrates
fatty acids
nucleotides
polysaccharides
nucleotides
The steps or rungs of the DNA ladder-like structure consists of complementary chemicals that are:
acetic acids
fatty acids
pairs of nitrogenous bases
sugar-phosphate compounds
pairs of nitrogenous bases
Compounds called purines include adenine and:
1. cytosine
2. guanine
3. thymine
1 only
2 only
3 only
1, 2, and 3
2 only
Which of the following serves as a prototype for messenger RNA (mRNA)?
Deoxyribonucleic acid (DNA)
Nitric acid (HNO3)
Potassium (K) and sodium (Na)
Transfer RNA (tRNA)
Deoxyribonucleic acid (DNA)
The cell components that contain the centrioles are the:
centrosomes
Golgi apparatus and mitochondria
lysosomes
ribosomes
centrosomes
The number of mitochondria in cells varies from a few hundred to several thousand. The greatest number is found in cells exhibiting _____ activity.
almost no
moderate
no
the greatest
the greatest
During which of the following subphases of mitosis do the centrioles migrate to opposite sides of the cell and begin to regulate the formation of the mitotic spindle?
Anaphase
Metaphase
Prophase
Telophase
Prophase
In the human body, mineral salts are necessary for:
1. proper cell function
2. creation of energy
3. conduction of impulses along nerves
1 and 2 only
1 and 3 only
2 and 3 only
1, 2, and 3
1, 2, and 3
Which of the following causes an increase in cellular activity that in turn causes biochemical reactions to occur more rapidly to meet the needs of the cell?
Acetic acids
Enzymes
Hormones
Nucleic acids
Enzymes
How many different amino acids are involved in protein synthesis?
7
15
22
39
22
A nucleotide is formed from a nitrogen-containing organic base, a _____-carbon sugar molecule, and a phosphate molecule.
three
five
seven
nine
five
Cytosine bonds only with:
adenine
guanine
nitrogen
thymine
guanine
In a DNA macromolecule, the sequence of ________ determines the characteristics of every living thing.
Sugars
Phosphates
Nitrogenous organic bases
Hydrogen bonds
Nitrogenous organic bases
Radiation-induced chromosome damage may be evaluated during which of the following processes?
Prophase
Metaphase
Anaphase
Telophase
Metaphase
If exposure to ionizing radiation damages the components involved in molecular synthesis beyond repair, cells do which of the following?
Continue to function normally
Function abnormally or die
Repair themselves immediately because of the enzymatic proteins they contain
Reproduce themselves in pairs
Function abnormally or die
Which of the following produces antibodies?
Erythrocytes
Lymphocytes
Thrombocytes
Platelets
Lymphocytes
Water constitutes approximately ________ of the weight of the human body.
30% to 35%
50% to 55%
65% to 70%
80% to 85%
80% to 85%
What term is used to describe chemical secretions that are manufactured by various endocrine glands and carried by the bloodstream to influence the activities of other parts of the body?
Amino acids
Antibodies
Hormones
Disaccharides
Hormones
Somatic cells divide through the process of:
Meiosis
Mitosis
Mapping
Metabolism
Mitosis