Klinefelter's syndrome is a result of which of the following
nondisjunction mutations?
A. deletion of chromosome 5
B. only an X chromosome
C. two X chromosomes and a Y
D. three copies of the 21st chromosome

In which of the following ways is the function of the surface of a microsphere similar to the function of an actual cell membrane? a. both make it possible for the conditions in the interior to be different from the conditions outside. b. both provide a barrier that keeps water from flowing across it so the interior remains dry. c. both separate the rna that forms in the interior from any rna that might form in the environment. d. both can actively move molecules into the interior or out into the surrounding environment.

Arrange the following in the correct sequence, from earliest to most recent, in which these plant traits originated. 1. sporophyte dominance, gametophyte independence 2. sporophyte dominance, gametophyte dependence 3. gametophyte dominance, sporophyte dependence a) 1 → 2 → 3 b) 2 → 3 → 1 c) 2 → 1 → 3 d) 3 → 2 → 1 e) 3 → 1 → 2

How did the discovery of the rhesus factor affect society? o more patients died from having a transfusion with the wrong rhesus factor 0 new treatments during pregnancy could prevent harm to the developing child. o less donated blood could be used in the treatment of patients. the number of blood types was reduced by half