What characteristic is common to most chordates, but is not a necessity?
a. Vertebrate
b. Pharyngeal gill slits
c. Postanal tail
d. Notochord
a
You might also like to view...
The clonal selection theory states that each antigen-reactive B cell or T cell has a cell surface receptor for a single antigen epitope
Indicate whether the statement is true or false.
Exotic, or introduced, species can permanently disrupt native communities when they ________
a. destroy crops or natural vegetation used by other species b. all of the choices c. prey on community members and depress their numbers d. outcompete native species for access to space, light, or nutrients
An organism that has behavioral strategies to manage the gain of heat from and the loss of heat to the environment, but lacks a physiological temperature-regulating mechanism, is termed a(n)
A. homotherm. B. endotherm. C. positherm. D. ectotherm. E. thermophile.
The chemical reactions in cells are called ____
a. substrate b. coenzymes c. receptor sites d. metabolism e. active site