Hoxc8 is nearly identical in all animals, but Hoxc8 enhancer differs in:
A) the RNA base sequence.
B) the DNA base sequence.
C) the sequence of amino acids.
D) the DNA base sequence and its DNA-binding proteins.
E) DNA-binding proteins.
Answer: D
You might also like to view...
How does the phenomenon of horizontal gene transfer muddle the concept of monophyletic groups?
A. Monophyletic groups are based on the concept that a particular group of species descended from a common ancestor. When horizontal gene transfer occurs in the common ancestor, any species to which it gives rise can no longer be considered descendent species. B. Monophyletic groups are based on the concept that a particular group of species descended from a common ancestor. When horizontal gene transfer occurs, not all of the genes in a species were inherited from the common ancestor. C. Monophyletic groups are based on the concept that members of a particular group of species are related to one another at a particular taxonomic rank. However, a species that undergoes horizontal gene transfer no longer belongs to that taxon and the group becomes paraphyletic. D. Monophyletic groups are based on the concept that members of a particular group of species are related to one another at a particular taxonomic rank. An unrelated species that undergoes horizontal gene transfer can become more closely related to members of a different group, making that group polyphyletic.
Second messengers are molecules of
a. steroid compounds. b. cyclic AMP. c. ADP. d. prostaglandin. e. intermedin.
Which of the following statements concerning B cell receptors (BCRs) is FALSE?
A) They are formed in response to an encounter with an antigen. B) They are complementary in shape to a specific antigenic determinant that they may or may not encounter. C) They are bound to the surface of B lymphocytes and have two antigen-binding sites. D) Each B lymphocyte is randomly generated with antibody variable regions that determine its BCR. E) Scientists estimate that each person forms at least 1011 different types of B lymphocytes with distinct BCRs.
Plasma membranes are extremely thin and fragile, requiring an extensive support network of fibrous proteins. This network is called the ____________
(a) cortex. (b) attachment complex. (c) cytoskeleton. (d) spectrin.