When Darwin covered the tip of a grass seedling with metal foil and then illuminated it from one side, what happened to the seedling?
A. It bent away from the directional light.
B. It did not respond to the directional light.
C. It grew toward the light, as expected.
D. It waved back and forth.
E. It wilted and died.
B. It did not respond to the directional light.
Charles Darwin and his son Francis, found that when a shoot tip was covered with foil, the shoot would not bend. This finding eventually led to the discovery of auxin.
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Which of the following type of organism is most likely an autotroph?
A. caribou B. lion C. human D. tree E. parasite
Which of the following regarding the haversian system is false?
A. Haversian canals may contain nerve fibers. B. Haversian canals run parallel to the length of long bone. C. It keeps osteocytes alive. D. Haversian canals are created by osteoclasts that tunnel through the bone matrix.
In the evolution of plants, wood appeared before seeds.
Answer the following statement true (T) or false (F)
Four genes (A, B, C, D) are in the same chromosome in the sequence D, A, B, C. The distance between A and B is 4 map units, between A and C is 6 map units, between B and C is 2 map units, and between B and D is 5 map units
The recombination frequency between genes C and D should be A. 2% B. 4% C. 5% D. 6% E. 7%