Which of the following extraembryonic membranes
is the first site of blood cell formation and the source
of germ cells?
a. amnion
b. yolk sac
c. chorion
d. allantois
e. none of these
Answer: b
Biology & Microbiology
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The figure above is an example of
A. punctuated equlibrium.
B. anogenesis.
C. gradualism.
D. speciation based on sexual selection.
E. anogenesis and speciation based on sexual selection.
Biology & Microbiology
Which of the following is a primary consumer?
a. tiger b. elephant c. eagle d. hyena e. snake
Biology & Microbiology
In multicelled species, spores germinate and give rise to filaments called __________. Fill in the blank(s) with the appropriate word(s)
Biology & Microbiology
What is the formula for determining the number of combinations of chromosomes that can be in gametes, where n is the number of chromosomes?
A) 2n B) n4 C) nn D) n2 E) 4n
Biology & Microbiology