Glucose-6-phosphate dehydrogenase deficiency (G6PD) is inherited as a recessive
allele of an X-linked gene in humans. A woman whose father suffered from G6PD
marries a normal man.
(a) What proportion of their sons is expected to be G6PD?
(b) If the husband was not normal but was G6PD deficient, would you change your
answer in part (a)?
A) (a) 100%; (b) no
B) (a) 1/2; (b) yes
C) (a) 1/2; (b) no
D) (a) zero; (b) no
You are given four test tubes, each containing an unknown protist, and your task is to
read the following description and match these four protists to the correct test tube.
When light, especially red and blue light, is shone on the tubes, oxygen bubbles
accumulate on the inside of test tubes 1 and 2. Chemical analysis of test tube 1 indicates
the presence of a chemical that is toxic to fish and humans. Chemical analysis of test
tube 2 indicates the presence of substantial amounts of silica. Microscopic analysis of
organisms in test tubes 1, 3, and 4 reveals the presence of permanent,
membrane-bounded sacs just under the plasma membrane. Microscopic analysis of
organisms in test tube 3 reveals the presence of an apicoplast in each. Microscopic
analysis of the contents in test tube 4 reveals the presence of one large nucleus and one
small nucleus in each organism.
Test tube 4 contains _____.
A) Paramecium
B) Pfiesteria (dinoflagellate)
C) Entamoeba
D) Plasmodium