In the human body which system functions in detecting and responding to stimuli?
a. endocrine
b. circulatory
c. muscular
d. nervous

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.

Describe your dna model. which part do the straws represent? the pushpins? the paper clips and the black dots you made with the marker?

What factors contribute to the effect an environmental toxin has on the human body?