As oxygen appeared in the atmosphere, ________ also accumulated, which formed a protective barrier that protects the Earth from ________
A) ozone / UV radiation
B) elemental sulfur / volcanism
C) ferrous iron / hydroxylating radicals
D) sulfate / hydrogen sulfide
Answer: A
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During this phase of the cell cycle chromosomes start to condense:
A. Metaphase B. Prometaphase C. Telophase D. Anaphase E. Prophase
An organism isolated from a sputum sample that has a "hockey puck" consistency would have which of the following biochemical profiles?
a. Glucose-positive, maltose-positive, and lactose-positive b. Glucose-positive, maltose-positive, and lactose-negative c. Glucose-positive, maltose-negative, and lactose-negative d. Glucose-negative, maltose-negative, and lactose-negative
Molecular relationships and other studies have allowed for many conidial fungi to be reclassified into a
fungal phylum. Most of these reclassified conidial fungi have turned out to belong to which fungal phylum?
a. Glomeromycota b. Basidiomycota c. Chytridiomycota d. Zygomycota e. Ascomycota
Very early in development, each cell is capable of expressing all its genes. This is referred to as
A. multipotency. B. bipotential induction. C. specification. D. totipotency. E. determination.