Page 33 - Science Course 2 (Book 1)

Mo2-L1b: Why are Organic Compounds Important?

nucleotide Like carbohydrates, lipids are made from carbon,
hydrogen, and oxygen.
a molecule made of a nitrogen base, a sugar, and a
phosphate group. Triglycerides, cholesterol, and some hormones,
such as estrogen and testosterone, are lipids.

Lipid
Lipids, also called fats, contain
fewer oxygen atoms than
carbohydrates and do not
Let’s Begin dissolve in water.

Elements and Compounds

The term organic describes compounds that contain Proteins form when amino acids, the building
carbon and other elements held together by covalent blocks of protein, join together.
bonds.
Some proteins give cells
Substances that form from joining many small structure, some help cells
molecules together are called macromolecules. communicate, and some
are enzymes.

All amino acids consist of carbon,
oxygen, hydrogen, and nitrogen.
Sugar polysaccharide Some also contain sulfur.

Amino Acid Protein Nucleic acids are formed when nucleotides,
molecules made of a nitrogen base, a sugar, and a
phosphate group, join together.

Nucleotide
The four macromolecules in the body are
carbohydrates, lipids, proteins, and nucleic acids. The body contains two types of nucleic acids, DNA
and RNA.
Sugars, starches, and cellulose are carbohydrates.

Carbohydrates are formed when simple sugars,
called monosaccharides, are joined together.

Carbohydrate
During digestion, humans break
down carbohydrates into glucose,
a monosaccharide, and store it as
glycogen.

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