Which of these characteristics added most to vertebrate success in relatively dry environments?
A) the shelled, amniotic egg
B) the ability to maintain a constant body temperature
C) two pairs of appendages
D) a four-chambered heart
A
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A 26-year-old woman has an odorous vaginal discharge, lower abdominal pain, and difficulty urinating. Vaginal secretions are collected and sent to the laboratory for examination 3 hours af-ter collection. No motile organisms are observed on the wet preparation; however, T. vaginalis is suspected. Which one of the following statements explains this discrepancy?
a. The infection is most likely bacterial; therefore a Gram stain should have been performed. b. The specimen should have been refrige-rated before examination; consequently, the organism was compromised. c. The time between collection and the mi-croscopic examination was prolonged, resulting in loss of motility. d. No discrepancy is present; this organism in nonmotile.
The term ____________________ refers to the relaxation phase of the cardiac cycle. Fill in the blank(s) with the appropriate word(s)
________ is the use of genes for treating human genetic disorders
A) Genetics B) Genomics C) Pharmacogenomics D) Gene therapy E) Recombinant DNA technology
As an adult human ages, the blood vessels lose their elasticity, and blood pressure drops as dilation occurs
Indicate whether the statement is true or false