Plant responses to the relative lengths of light and dark periods in their environment during each 24-
hour period are
a. gravitropisms.
b. photoperiodisms.
c. thigmotropisms.
d. circadian rhythms.
e. phototropisms.
B
You might also like to view...
A normal gene that codes for proteins involved in cell division is a(n) ____
Chapter 22 - Genes and Disease - Cancer Copyright Cengage Learning. Powered by Cognero. Page 4 a. proto-oncogene b. pre-oncogene c. post-oncogene d. dys-oncogene e. oncogene
In a dihybrid cross exhibiting complete genetic linkage, what would you expect?
A) one parental allele combination occurring more frequently than another B) two equally frequent gametes containing only parental allele combinations C) only recombinant gametes D) one parental allele combination occurring more frequently than another and no recombinant gametes E) two equally frequent gametes containing only parental allele combinations and no recombinant gametes
Exotoxins, produced by Gram-negative bacteria, are highly antigenic and can be inactivated to form toxoids and used as vaccines.
a. true b. false
What stimulates germination of desert plant seeds after a hard rain?
A) production of auxins B) removal of abscisic acid C) cooler temperatures D) activation of cytokinins