At some stage of the life cycle, all chordates have
A) a pre-anal tail.
B) an external skeleton.
C) a ventral nerve cord.
D) a backbone.
E) pharyngeal gill slits.
E
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In the Igf2 gene, which allele is imprinted? Which is expressed?
A. Paternal, paternal B. Paternal, maternal C. Maternal, paternal D. Maternal, maternal
A man who is an achondroplastic dwarf with normal vision marries a color-blind woman of normal height. The man's father was six feet tall, and both the woman's parents were of average height
Achondroplastic dwarfism is autosomal dominant, and red-green color blindness is X-linked recessive. How many of their daughters might be expected to be color-blind dwarfs? A) none B) half C) one out of four D) three out of four
The first stage of aerobic respiration is a series of biochemical reactions called the Calvin cycle.
a. true b. false
Answer the following questions true (T) or false (F)
1. What causes geographic isolation for one kind of organism may not be isolating for another kind of organism. 2. Speciation can occur without dramatic anatomical or genetic change. 3. Speciation can never occur unless populations become separated by a geographic barrier.