You have just invented a time machine and you want to investigate the past (the dream of every paleontologist!). When is the earliest time in Earth history that you could go back and not have to have an oxygen tank so that you could breathe normally?
A. Cambrian Period
B. Phanerozoic Eon
C. Archaean Eon
D. Quaternary Period
E. Devonian Period
A. Cambrian Period
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A developer putting tract housing in a previously pristine area plans numerous small, open space areas where the
original habitat is to remain. As a conservationist, how would you suggest changing the plan, if at all (assume that canceling the development is not an option)? Why?
What will be an ideal response?What is the main structural component of cell membranes?
a. Polypeptides b. Triglycerides c. Enzymes d. Phospholipids
The corpus luteum is located in the
A) penis. B) ovary. C) testis. D) uterus. E) vagina.
You are a medical microbiologist in Dallas, TX. A small population of individuals spread throughout the city have been experiencing alarming yet similar symptoms affecting the liver that have physicians puzzled as to the etiology, although they all suspect it is microbial in nature. What steps would you take to elucidate the organism?
A. 1. Biopsy the patient's liver to look for organisms; 2. Culture the organisms obtained from the liver and run biochemical tests to determine similarities to other known liver pathogens; 3. Inoculate liver pathogens into lab animals to compare symptoms. B. 1. Sample the livers from affected patients to culture and compare organisms; 2. Grow the suspected organisms in culture; 3. Inoculate the cultured organisms into a laboratory animal and monitor for similar symptoms; 4. Culture and analyze the organism from the lab animal and determine relatedness. C. 1. Inoculate all suspected organisms into a laboratory animal and monitor for similar symptoms; 2. Biopsy the original patient's liver to look for organisms; 3. Grow the suspected organisms from the liver in culture; 4. Culture and analyze the organism from the lab animal and determine relatedness. D. Sample the livers of all sick individuals and culture the organisms, comparing symptoms and microscopic characteristics.