Chapter 9

Question 1

conjugation

Answer 1

the union between two bacterial cells
enabling the direct transfer of genetic material from
one to the other

Question 2

master control gene

Answer 2

a gene that coordinates
expression of many other genes to control
body patterning and cell differentiation during
embryonic development;

Question 3

molecular clock

Answer 3

the number of substitutions that
have accumulated in the amino acid sequence
of a polypeptide or the nucleotide sequence of a
gene in a given lineage; the rate of the molecular
clock is used to estimate the time since two species
diverged

Question 4

phyletic evolution

Answer 4

successive evolution of one
species into another within a single evolutionary
lineage

Question 5

pseudogene

Answer 5

an obsolete gene for which there are
no functional alleles, a consequence of inactivation
by mutation during evolution

Question 6

novel gene

Answer 6

Benefic\il function