1. Chapter 2 Cell Structure and Function
Lesson 1: Cells and Life (pages 42 – 48)

2. Basic Cell Substances What is a macromolecule?
Large organic molecules that form when smaller molecules are joined together.
Many times made up of repeating subunits.

3. Basic Cell Substances Water: Essential to all life
Makes up 70 percent of a cell’s volume.
Surrounds and insulates cells to help maintain homeostasis.
Dissolves substances so they can move in and out of the cell.

4. Basic Cell Substances Water
The chemical properties of water help it to dissolve substances.
Negative end
Positive end

5. Basic Cell Substances Water
The negative and positive ends help water dissolve substances such as salt.

6. Basic Cell Substances
Why is it important for cells to have substances dissolved in water?
Large Molecules – such as glucose - need to be dissolved (in liquid form) in order to pass in and out of the cell.
Water
Oxygen
Carbon Dioxide
Glucose

7. Basic Cell Substances
Four Basic Macromolecules that make up living cells.
Carbohydrate
Protein
Lipids
Nucleic Acids

8. Major role in living things
Macromolecules
Macromolecule
Description
Examples
Major role in living things
Macromolecules made up of long chains of nucleotides.
-Contain genetic information that is passed from parent to offspring.
DNA or RNA
Nucleic Acid
Macromolecules made up of long chains of amino acids.
-help cells communicate
-transport substances
-break down nutrients
-provide structural support
amylase, keratin
Protein
A large macromolecule that does not dissolve in water.
-help form protective barriers
-major part of cell membrane
-energy storage
-help cells communicate
cholesterol, phospholipids, vitamin A
Lipid
A macromolecule made up of one simple sugar, or a long chain of sugars molecules
sugar (fruit) and starches (bread)
-structural support
-energy storage
-help cells communicate
Carbohydrate

9. Carbohydrates Sugars and starches are both examples of carbohydrates.
What is the relationship between a sugar and a starch?
Glucose (sugar)
Starch

10. Nucleic Acids
Nucleic Acids - such as DNA and RNA - are made up of repeating units called Nucleotides.

11. Proteins
Proteins are made up of repeating units called amino acids.

12. Lipids Large macromolecules that are not soluble in water.
This inability to dissolve in water allows lipids to form protective barriers in cells.
Lipids are the major component in cell membranes