Download Name Class Date Skills Worksheet Directed Reading B Section

Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading B
Section: Elements in Living Things
THE BONDING OF CARBON ATOMS
1. Name two reasons why carbon has a central role in the chemistry of living organisms.
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2. Each carbon atom has ______________________ valence electrons.
3. Each carbon atom can make a total of ______________________ bonds.
4. Models of carbon backbones show how ______________________.
5. A covalently bonded compound that contains carbon is called
a(n) ______________________.
Match the correct description with the correct term. Write the letter in the space provided.
_____ 6. type of bond carbon atoms most often form
_____ 7. simplest example of an organic compound
with a double bond
a.
b.
c.
d.
propane
ethyne
single bond
ethene
_____ 8. compound whose carbon atoms have only
single bonds
_____ 9. organic compound that has triple bonds between carbon atoms
OTHER ELEMENTS IN LIVING ORGANISMS
10. What type of compounds do all living things depend on?
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Name ______________________________ Class __________________ Date __________________
Directed Reading B continued
11. Name the six elements that make up most of the human body.
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12. What do carbon’s special bonding abilities allow carbon to do?
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13. Name two types of organic compounds that can be manufactured.
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Name ______________________________ Class __________________ Date __________________
Skills Worksheet
Directed Reading B
Section: Compounds of Living Things
Write the letter of the correct answer in the space provided.
_____ 1. Carbohydrates, lipids, proteins, and nucleic acids are the four
categories of
a. living things.
b. carbons.
c. organic compounds.
d. biochemicals.
CARBOHYDRATES
_____ 2. Carbohydrates are biochemicals that are composed of one or more
a. lipids.
b. sugar molecules.
c. organic compounds.
d. starch molecules.
_____ 3. Simple carbohydrates are made up of
a. simple sugars.
b. cellulose.
c. proteins.
d. lipids.
_____ 4. Complex carbohydrates may be made of thousands of
a. lipids.
b. simple sugars.
c. proteins.
d. nucleic acids.
_____ 5. Living things commonly use carbohydrates as a source of
a. fat.
b. genetic material.
c. energy.
d. protein.
LIPIDS
_____ 6. Lipids are biochemicals that do not
a. store excess energy.
b. make up cell membranes.
c. dissolve in water.
d. store vitamins.
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