1. Unit 1 Lesson 2 Chemistry of Life
Essential Question: What are the building blocks of organisms?
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2. It’s Elementary What are atoms and molecules?
Unit 1 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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3. What are atoms and molecules?
Unit 1 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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4. What are atoms and molecules?
Unit 1 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 up of only one type of atom.
Most molecules are made up of two or more types of atoms.
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5. What are atoms and molecules?
Unit 1 Lesson 2 Chemistry of Life
What are atoms and molecules?
A compound is a substance made up of atoms of two or more elements joined by chemical bonds.
Most molecules found in cells are compounds.
Compounds have different properties than the elements that make them.
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6. Cell Fuel What are some important types of molecules in cells?
Unit 1 Lesson 2 Chemistry of Life
Cell Fuel
What are some important types of 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 have many jobs in cells, such as storing energy.
Your cells get lipids from foods such as olive oil and fish.
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7. What are some important types of molecules in cells?
Unit 1 Lesson 2 Chemistry of Life
What are some important types of molecules in cells?
A protein is a molecule made up of smaller molecules called 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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8. What are some important types of molecules in cells?
Unit 1 Lesson 2 Chemistry of Life
What are some important types of molecules in cells?
Carbohydrates are molecules that include sugars, starches, and fiber.
Cells use carbohydrates for energy and energy storage.
Simple carbohydrates are made of one or a few sugars linked together. Complex carbohydrates contain many sugar molecules linked together.
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9. What are some important types of molecules in cells?
Unit 1 Lesson 2 Chemistry of Life
What are some important types of 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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10. Waterworks What are phospholipids?
Unit 1 Lesson 2 Chemistry of Life
Waterworks
What are phospholipids?
A lipid that contains phosphorus is called a phospholipid.
The head of a phospholipid molecule is attracted to water. The tail repels water.
Much of a cell’s membrane is made of a double-layer of phospholipids, which regulates molecules entering and leaving the cell.
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11. What are phospholipids?
Unit 1 Lesson 2 Chemistry of Life
What are phospholipids?
What causes a cell membrane to have a double-layer structure?
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12. Unit 1 Lesson 2 Chemistry of Life
Why is water important?
Water moves through a cell membrane by a process called osmosis.
Water moves into and out of a cell, from areas of higher concentration to areas of lower concentration.
Too little water in a cell causes it to shrink.
Too much water in a cell causes it to burst.
All chemical process that take place in cells, take place in the presence of water
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