1. the first trimester of prenatal human development
a>last about ten weeks after fertilization
b>is know as the period of embryogenesis
c>is when most development peoblems occurs
d>all of the above
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2. at each higher tropic level
a>only about 10% of the energy from the next lower trophiclevel can be used
b>'' 70% '' ''
c>more energy is available in the food web
d> none of the above
the answer is A ?
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3. J-shaped population patterns are often seen
a> in long-lived species
b> in short-lived species
c>when population growth is independent of density
d>b and c only
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4. climate effect global warming include
a>the beginning of a new ice age
b>a rise in sea level
c>expansion of desert area
d>b and c only