In a bacterial cell, the DNA is in the:
A) cell envelope.
B) cell membrane.
C) nucleoid.
D) nucleus.
E) ribosomes. - Answers C) nucleoid.
A major change occurring in the evolution of eukaryotes from prokaryotes was the development
of:
A) DNA.
B) photosynthetic capability.
C) plasma membranes.
D) ribosomes.
E) the nucleus. - Answers E) the nucleus
In eukaryotes, the nucleus is enclosed by a double membrane called the:
A) cell membrane.
B) nuclear envelope.
C) nucleolus.
D) nucleoplasm.
E) nucleosome. - Answers B) nuclear envelope
The dimensions of living cells are limited, on the lower end by the minimum number of
biomolecules necessary for function, and on the upper end by the rate of diffusion of solutes
such as oxygen. Except for highly elongated cells, they usually have lengths and diameters in
,the range of:
A) 0.1 m to 10 m.
B) 0.3 m to 30 m.
C) 0.3 m to 100 m.
D) 1 m to 100 m.
E) 1 m to 300 m. - Answers C) 0.3 m to 100 m.
Which group of single-celled microorganisms has many members found growing in extreme
environments?
A) Bacteria
B) Archaea
C) Eukaryotes
D) Heterotrophs
E) None of the above - Answers B) Archaea
The bacterium E. coli requires simple organic molecules for growth and energy—it is therefore a:
A) chemoautotroph.
B) chemoheterotroph.
C) lithotroph.
D) photoautotroph.
E) photoheterotroph. - Answers B) chemoheterotroph.
Which one of the following has the cellular components arranged in order of increasing size?
A) Amino acid < protein < mitochondrion < ribosome
B) Amino acid < protein < ribosome < mitochondrion
, C) Amino acid < ribosome < protein < mitochondrion
D) Protein < amino acid < mitochondrion < ribosome
E) Protein < ribosome < mitochondrion < amino acid - Answers B) Amino acid < protein <
ribosome < mitochondrion
The three-dimensional structure of macromolecules is formed and maintained primarily through
noncovalent interactions. Which one of the following is not considered a noncovalent
interaction?
A) carbon-carbon bonds
B) hydrogen bonds
C) hydrophobic interactions
D) ionic interactions
E) van der Waals interactions - Answers A) carbon-carbon bonds
Which one of the following is not among the four most abundant elements in living organisms?
A) Carbon
B) Hydrogen
C) Nitrogen
D) Oxygen
E) Phosphorus - Answers E) Phosphorus
The four covalent bonds in methane (CH4) are arranged around carbon to give which one of the
following geometries?
A) Linear
B) Tetrahedral
C) Trigonal bipyramidal
D) Trigonal planar