Jawless fishes were the first vertebrates to leave fossil evidence during the _____ period.
A. Cambrian
B. Devonian
C. Carboniferous
D. Silurian
E. Ordovician
E. Ordovician
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Increased concentrations of CO2 (5% to 10%) and approximately 15% O2 produce an environ-mental condition that best suits which type of organism?
a. Aerobes b. Anaerobes c. Capnophiles d. Microaerophiles
The phase of the bacterial growth curve in which newly inoculated cells are adjusting to their new environment, metabolizing but not growing at an exponential rate, is the ________.
A. stationary phase B. lag phase C. exponential phase D. prophase E. death phase
Scientists are now using an expanded definition of intelligence, beyond IQ, called
____________________. Fill in the blank(s) with the appropriate word(s).
What is the difference between covalent and ionic bonds?
A) Covalent bonds involve the sharing of neutrons, whereas ionic bonds involve the attraction of slightly charged atoms. B) Covalent bonds involve the attraction between slightly charged molecules, whereas ionic bonds involve the attraction between two fully charged ions. C) Covalent bonds involve the sharing of electrons, whereas ionic bonds involve the transfer of electrons from one atom to another. D) Covalent bonds involve the sharing of electrons, whereas ionic bonds involve the sharing of protons.