Today's atmosphere on Earth is made up of nitrogen, oxygen, carbon dioxide, and water. According to all models, which of these was largely absent 3.8 billion years ago?
A) oxygen
B) nitrogen
C) carbon dioxide
D) water
A
Biology & Microbiology
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The branch of microbiology that deals with diseases of humans and animals is called ________ microbiology.
Fill in the blank(s) with the appropriate word(s).
Biology & Microbiology
When examining a mutant mouse, you notice that its skeletal muscle looks very uniform, lacking in striations. To figure out what the mutation is in this mouse, you would begin by looking at
A. sarcomere organization. B. the retention of calcium in the endoplasmic reticulum. C. tendons. D. the blood vessels in the muscles. E. the sheath around muscles.
Biology & Microbiology
The only antibody not secreted in significant amounts by B cells.
What will be an ideal response?
Biology & Microbiology
how plants defy gravity
What will be an ideal response?
Biology & Microbiology