Explain which process evolved first-glycolysis or the Krebs cycle.
What will be an ideal response?
Glycolysis evolved first because cells of all types of organisms are capable of this process. The Krebs cycle did not arise until after photosynthetic organisms began adding oxygen to the atmosphere because the Krebs cycle requires oxygen, while glycolysis does not.
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Which vitamin is found in leafy green vegetables and is necessary for proper blood clotting?
a. vitamin D b. vitamin E c. vitamin K d. vitamin A e. thiamin
Refer to Figure 46-1. The structures receiving air in figure 1 are known as:
a. anterior air sacs. b. parabronchi. c. spiracles. d. alveoli. e. tracheae.
Examine the picture to answer the following questions and identify the labeled structures. 
A:________B:________C:________D:________E:________F:________G:________H: Is the neuron pictured a sensory, association or motor neuron? What is its function?I:Is the neuron multipolar or unipolar? Explain your answer.
What will be an ideal response?
What is the advantage of having small, needlelike leaves?
A) increased transpiration rate B) decreased transpiration rate C) increased efficiency of light capture D) decreased efficiency of light capture