The first cells were formed approximately ___________ years ago.
a. 3 million years ago
b. 3 billion years ago
c. 2 billion years ago
Answer: b. 3 billion years ago
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The maximum density of pure water occurs at:
a. -2° C. b. 0° C. c. 3° C. d. 4° C. e. -4° C.
Which statement about the accompanying figures is true?
a. Figure B has a smaller volume than Figure A.
b. Figure B has a greater volume than Figure A.
c. Figure B has a greater surface area than Figure A.
d. Figure B has a greater surface area to volume ratio than Figure A.
e. Figure B has a smaller surface area to volume ratio than Figure A.
Density-independent factors are abiotic.
Indicate whether the statement is true or false
In his transformation experiments, which of the following results did Griffith observe?
A) Mutant mice were resistant to bacterial infections. B) Mixing a heat-killed pathogenic strain of bacteria with a living nonpathogenic strain can convert some of the living cells into the pathogenic form. C) Mixing a heat-killed nonpathogenic strain of bacteria with a living pathogenic strain makes the pathogenic strain nonpathogenic. D) Infecting mice with nonpathogenic strains of bacteria makes them resistant to pathogenic strains.