Unit 6 Lesson 2 Chemistry of Life
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Unit 6 Lesson 2 Chemistry of Life
Indiana Standards
• 7.3.1 Explain that all living organisms are
composed of one or more cells and that the many
functions needed to sustain life are carried out
within such cells.
• 7.3.2 Understand that water is a major
component within all cells and is required to carry
out many cellular functions.
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Unit 6 Lesson 2 Chemistry of Life
It’s Elementary
What are atoms and molecules?
• All cells (and all matter) are made up of atoms
and molecules.
• An element is a substance that cannot be broken
down into a simpler substance.
• The smallest unit of an element that maintains the
properties of that element is called an atom.
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Unit 6 Lesson 2 Chemistry of Life
What are atoms and molecules?
• What are the six main elements that make up the
human body?
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Unit 6 Lesson 2 Chemistry of Life
What are atoms and molecules?
• A molecule is a group of atoms held together by
chemical bonds.
• Some molecules are made of only one type of
atom.
• Most molecules are made of two or more types of
atoms.
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Unit 6 Lesson 2 Chemistry of Life
What are atoms and molecules?
• Cells are mostly made of compounds.
• Compounds are substances made up of two or
more elements joined by chemical bonds.
• Compounds have different properties than the
elements that make them.
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Unit 6 Lesson 2 Chemistry of Life
Cell Fuel
What are some important molecules in
cells?
• Organisms use nutrients for energy and as
building materials.
• A lipid is a fat molecule or a molecule that has
similar properties. Lipids store energy in cells.
• Your cells get lipids from the foods you eat.
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Unit 6 Lesson 2 Chemistry of Life
What are some important molecules in
cells?
• A protein is a molecule made up of amino acids.
• Protein-rich foods are broken down into amino
acids, which make new proteins to build and
repair body structures.
• Proteins called enzymes help chemical processes
happen in cells.
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Unit 6 Lesson 2 Chemistry of Life
What are some important molecules in
cells?
• Carbohydrates are molecules that include
sugars, starches, and fiber.
• Cells use carbohydrates for energy and energy
storage.
• Carbohydrates can be simple carbohydrates or
complex carbohydrates.
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Unit 6 Lesson 2 Chemistry of Life
What are some important molecules in
cells?
• Nucleic acids are molecules that carry
information in cells.
• Nucleotides are the smaller molecules that make
up nucleic acids.
• DNA is a nucleic acid that carries information that
cells need to make other molecules.
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Unit 6 Lesson 2 Chemistry of Life
Waterworks
What are phospholipids?
• A lipid that contains phosphorus is called a
phospholipid.
• The head of a phospholipid is attracted to water.
The tail repels water.
• A double-layer cell membrane, made of
phospholipids, regulates molecules entering and
leaving a cell.
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Unit 6 Lesson 2 Chemistry of Life
What are phospholipids?
• What causes a cell membrane to have a doublelayer structure?
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Unit 6 Lesson 2 Chemistry of Life
Why is water important?
• Water moves through a cell membrane by
osmosis.
• Water moves into and out of a cell, from areas of
higher concentration to areas of lower
concentration.
• Too little water causes cells to shrink.
• Too much water causes cells to burst.
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