1. Unit 1 Lesson 2 Chemistry of Life
Copyright © Houghton Mifflin Harcourt Publishing Company

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.
Copyright © Houghton Mifflin Harcourt Publishing Company 2

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?
Copyright © Houghton Mifflin Harcourt Publishing Company 3

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.
Copyright © Houghton Mifflin Harcourt Publishing Company 4

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.
Copyright © Houghton Mifflin Harcourt Publishing Company 5

6. What is a macromolecule?
Macro = large
There are 4 groups of large molecules that are found in large quantities in our bodies.
They are:
Carbohydrates Proteins Lipids
and
Nucleic Acids
Macromolecules are polymers.
Poly- = many
-mer = unit
Polymers are long molecules built by linking repeating building blocks or units in a chain

7. A Polymer EXAMPLE of POLYMER MONOMER A TRAIN ? A NECKLACE
Here are some analogies to better understand what polymers and monomers are….
EXAMPLE of POLYMER
MONOMER
A TRAIN ?
A NECKLACE
If the train is the whole polymer, what would be the small groups that make up the train? If the necklace is the polymer, what are the monomers that make up the necklace?

8. Look at the label to the left
Look at the label to the left. 3 of the 4 macromolecules can be found in foods. Organisms use nutrients for energy and as building materials
FAT
(0 grams in this product)
Carbohydrates
(13 grams in this product)
Protein
(9 grams in this product)

9. When studying these biochemical molecules, we are interested in finding out…..
what they do for living things.
what they generally look like.
what their monomers are.
and how they may help the body gain energy to sustain life.

10. 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 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, butter, nuts and fish.
They are made up of chains of triglycerides
Copyright © Houghton Mifflin Harcourt Publishing Company 10

11. LIPIDS – What do they do
They are a great source of STORED ENERGY so we have it in the future.
They INSULATE the body to maintain normal body temperature and they CUSHION the internal organs for protection.
They produce hormones for the body called STERIODS
They waterproof surfaces of animals,plants, and fruits- these are waxes!
THINK: Waterproof, insulate, steriods, energy, cushion… “WISE C”

12. What are phospholipids?
Unit 1 Lesson 2 Chemistry of Life
What are phospholipids?
What causes a cell membrane to have a double-layer structure?
Copyright © Houghton Mifflin Harcourt Publishing Company 12

13. 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.
Copyright © Houghton Mifflin Harcourt Publishing Company 13

14. 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.
Copyright © Houghton Mifflin Harcourt Publishing Company 14

15. 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.
You do not get energy from nucleic acids
Copyright © Houghton Mifflin Harcourt Publishing Company 15

16. Energy that we gain by the consumption of food is measured in Calories.
If you drink a glass of skim milk, you will get a gain of 90 Calories of energy for your body.

17. Energy Gained From Carbohydrates
Eating 1 gram of carbohydrate provides your body with 4 Calories.

18. Energy Gained from Protein
Eating 1 gram of protein provides your body with 4 Calories.

19. Energy Gained from Lipids
Eating 1 gram of fat provides your body with 9 Calories.
Notice if you eat 1 gram of fat, you are gaining more than twice the amount of Calories than from a gram of carbohydrate or protein!

20. Number of Calories it provides
ENERGY
So…
BIG 4 MACROMOLECULES
Number of Calories it provides
Carbohydrates 4
Proteins
Lipids 9
Nucleic Acids
TEST: Are you smart? If you eat a sandwhich with 46 grams of carbs and 24 grams of protein and 10 grams of fat, how much energy will you gain?
370

21. 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.
Copyright © Houghton Mifflin Harcourt Publishing Company 21

22. 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.
Copyright © Houghton Mifflin Harcourt Publishing Company 22