Write the letter of the matching definition next to each term.
1. compound
A. An essential structural component of living cells and source of energy for animals (plural)
2. boron
B. A cellular structure that is postulated to exist in order to mediate between a chemical agent
3. oxygen
C. Having cells that lack membrane-bound nuclei
4. covalent
D. Characteristic life processes and phenomena of living organisms
5. ionic
E. Having cells with `good' or membrane-bound nuclei
6. hydrogen
F. An abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous ___
7. organic
G. An elementary particle with 0 charge and mass about equal to a proton
8. aminoacids
H. A microscopic network of actin filaments and microtubules in the cytoplasm of many living cells
9. eukaryotic
I. A writing implement for making a mark
10. prokaryotic
J. A state of being carried away by overwhelming emotion
11. transport
K. Organic compounds containing an ___ group and a carboxylic ___ group (plural)
12. marker
L. A fertilizer that is derived from animal or vegetable matter
13. receptor
M. An elementary particle with negative charge
14. electron
N. The dialect of Ancient Greek spoken and written in Attica and Athens and ___
15. proton
O. The smallest component of an element having the chemical properties of the element
16. neutron
P. A substance formed by chemical union of two or more elements or ingredients in definite proportion
17. atom
Q. A stable particle with positive charge equal to the negative charge of an electron
18. inorganic
R. Of or relating to or characterized by ___
19. carbon
S. Nutrient in meat and beans that builds muscle
20. carbohydrates
T. Gas in the air that we need to breathe
21. protein
U. A trivalent metalloid element
22. Biology
V. Relating or belonging to the class of compounds not having a carbon basis
23. cytoskeleton
W. A nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic