1) the first eukaryotic cells probably arose about _____ billion years ago.
a. 2.2
b. 2.5
c. 3.5
d. 4.5
2) if you are trying to alter the defensive mechanisms of a plant, which component of
the signal transduction pathway would be the ideal place to do this?
a. alter the receptor molecule on the plasma membrane, cytoplasm or nucleus.
b. block the relay proteins within the cytoplasm that will convert the signal.
c. change the gene expression or the cellular process that affects the plants growth.
d. all of these would alter the defensive mechanisms of the plant.
3) identify the correct sequence of events that occur during the reproduction of hiv.
a. virus attaches to a host cell – the virus enters the cell – viral dna is incorporated into
the host dna – reverse transcriptase occurs -viral / host dna is turned into a viral mrna
code – the viral rna forms into a mature virus – mature viruses leave the host cell
b. virus attaches to a host cell – the virus enters the cell – reverse transcriptase occurs –
viral dna is incorporated into the host dna – viral / host dna is turned into a viral mrna
code – the viral rna forms into a mature virus – mature viruses leave the host cell
c. virus attaches to a host cell – the virus enters the cell – viral dna is incorporated into
the host dna – reverse transcriptase occurs -the viral rna forms into a mature virus – viral
/ host dna is turned into a viral mrna code – mature viruses leave the host cell
d. virus attaches to a host cell – the virus enters the cell – viral / host dna is turned into a
viral mrna code -viral dna is incorporated into the host dna – reverse transcriptase
occurs -the viral rna forms into a mature virus – mature viruses leave the host cell
4) in a phospholipid bilayer, the
a. phosphate groups are hydrophobic.
b. fatty acid tails are ionized.
c. fatty acid tails are hydrophilic.
d. proteins are located only between the two layers.
e. phosphate heads are oriented toward the exterior of the cell or toward the cytoplasm.
incorrect
5) which naturalist wrote a 44-volume natural history on plants and animals, and
suggested migration, environmental influences, isolation, and overcrowding might
affect how organisms descend with modifications?
a. darwin
b. lamarck
c. cuvier
d. lyell
e. leclerc
6) the dilemma of whether proteins or nucleic acids were formed first is avoided by the
a. protein-first hypothesis.
b. rna-first hypothesis.
c. clay-catalyst hypothesis.
7) which of the following statements about steroid hormones is not true?
a. estrogen is a steroid hormone.
b. steroid hormones do not bind to cell surface receptors.
c. the hormone-receptor complex can enter the nucleus.
d. the hormone-receptor complex can bind to chromatin.
e. steroid hormones act faster than non-steroid (peptide) hormones.
8) male fireflies are recognized by females of their species by the pattern of their
flashings, while male crickets are recognized by females of their species by their
chirping. these are examples of _____.
a. behavioral isolation
b. habitat isolation
c. temporal isolation
d. mechanical isolation
9) in the use of a punnett square for genetic results of crossing individuals
a. all different kinds of sperm are lined up either horizontally or vertically.
b. all different kinds of eggs are lined up either horizontally or vertically.
c. the results show the offspring’s expected genotypes.
d. all of the choices are correct.
e. only two of the choices are correct.
10) what were the tools of cro-magnon man made from?
a. stone
b. metal
c. wood
d. wood that had been hardened in a fire to increase it’s strength
e. none of the above.