h. “big eaters” that alert other lymphocytes to the invasion of specific antigens
i. immature cells that may or may not be committed to develop into one of several
mature cell types
j. a group of cells that are all produced asexually from one original parent cell
k. surface patterns of nonself molecules or particles
l. proteins released by cytotoxic T cells to destroy target cell membranes
m. preparation injected into the body to elicit a primary immune response
n. one of this group has been identified as the causative agent of AIDS
Target cell
Choose the one most appropriate answer for each. Some letters may not be used.
a. flower each successive year or after several years of vegetative growth
b. promotes cell elongation in stems
c. has receptor sites for a particular hormonal message
d. a hollow, cylindrical organ that protects young leaves growing within it
e. blue-green pigment that absorbs light energy
f. low-temperature stimulation of flowering
g. stimulates stomata closure and might be involved in root geotropism
h. stimulates fruit ripening
i. reproduces in spring
j. produces only roots, stems, and leaves the first growing season and produces flowers
the second year