After fertilization, a zygote develops into a fully formed human in about 38 weeks. During which stage of development do cells begin to differentiate and form specialized tissues and organs?
A) first trimester
B) second trimester
C) third trimester
D) at birth
Ans: A) first trimester
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Which is an example of active immunity?
A. antibodies produced from a vaccine, or a person receiving an injection of antibodies B. a fetus acquiring antibodies through the placenta, or a person receiving an injection of antibodies C. a person receiving an injection of antibodies D. a fetus acquiring antibodies through the placenta E. antibodies produced from a vaccine
When listening to a patient's heart with a stethoscope, a physician hears an abnormality in the "lub DUB" sounds of the heart valves. He has detected ________.
Fill in the blank(s) with the appropriate word(s).
Gene therapy has not yet cured any patients of their genetic disorder. Indicate whether the statement is true or false
Answer the following questions true (T) or false (F)
1. Vaginosis may be experienced without accompanying vaginitis, but vaginitis always accompanies vaginosis. 2. A vaginal swab examined under the microscope reveals the presence of clue cells. Bacterial vaginosis is likely indicated. 3. Men, rather than women, make up the majority of syphilis cases.