Which of the following helps direct the formation of the primitive streak but contributes no cells to the embryo?
A) endoderm
B) mesoderm
C) ectoderm
D) neural crest
E) hypoblast
Answer: E) hypoblast
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Why do plants growing outside often have shorter and thicker stems than plants of the same species grown indoors?
A. The plants inside have a more constant source of light and therefore a higher level of phytochrome. B. The outdoor plants are subject to mechanical stresses and they are exhibiting a thigmomorphogenic response. C. The outdoor plants are subject to touch by animals and other plants and are exhibiting a thigmotropic response. D. The indoor plants have elevated levels of auxin and are therefore taller than the outside plants. Clarify Question · What is the key concept addressed by the question? · What type of thinking is required? · What key words does the question contain and what do they mean? Gather Content · What do you already know about growth of protected vs. exposed plants? How does it relate to the question? Consider Possibilities · What other information is related to the question? Which information is most useful? Choose Answer · Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer? Reflect on Process · Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
The first land animals were probably the:a
arthropods. b. amphibians. c. reptiles. d. mammals. e. dinosaurs.
Convert 500 mg to g.
A. 50 B. 5000 C. 0.5 D. 0.05
Transpiration in plants requires _____
I) adhesion of water molecules to cellulose II) cohesion between water molecules III) evaporation of water molecules IV) active transport through xylem cells V) transport through tracheids A) I, III, IV, and V B) I, II, IV, and V C) I, II, III, and V D) I, II, III, and IV