Non-functional xylem in the center of a tree trunk is

A. Summerwood

B. Sapwood

C. Heartwood

D. springwood

Which medullary index indicates a human hair? a. 0.653 b. 0.733 c. 0.516 d. 0.256

Give three examples of plant activities that are affected by circadian rhythms and natural fluctuations in the length of daylight?

This is a typical grassland food web. it is also a small picture of an important cycle on earth: the carbon cycle. describe how the carbon gets into this food web. a) bacteria and fungi, the decomposers, recycle carbon from dead organisms. b) carbon is found in the grass and is passed from one level to the next in this food web. eliminate c) all living things give off carbon dioxide as a by-product of respiration and it is released into the atmosphere. d) plants use carbon dioxide as a reactant in photosynthesis, to make usable chemical energy in the form of a sugar.