“In the beginning God created the heavens and earth...”

-

Gen 1:1

Block 3 Nielsen, Caleb Chaverri, Patrick Merritt, Emily

Welcome to

Biology!

Front of the room Lee, Sung Jin "Felix” Roccuzzo, John Loria, Charles Gulick, Emma Wolf, Elijah Meyer, Nicolas Georgina Santhosh Smith, Bethany Obrecht, Nathaniel Michaela Korman D'Haiti, David Schneider Christian Jiao, Peng "Anna"

“In the beginning God created the heavens and earth...”

-

Gen 1:1 Welcome to

Biology!

Front of the room Block 3 Nielsen, Caleb Chaverri, Patrick Merritt, Emily Lee, Sung Jin "Felix” Roccuzzo, John Loria, Charles Meyer, Nicolas Gulick, Emma Georgina Santhosh Wolf, Elijah Smith, Bethany Obrecht, Nathaniel Michaela Korman D'Haiti, David Schneider Christian Jiao, Peng "Anna"

Carbon is the main ingredient of organic macromolecules.

(Concept 5.1 )

page 92

Carbon Skeletons and Functional Groups

 organic molecule: carbon-based molecule  inorganic molecule: non-carbon-based molecule  hydrocarbon: organic molecule composed of only carbon and hydrogen atoms  E.g Methane: CH 4 gas. most abundant hydrocarbons in natural

Carbon Skeletons and Functional Groups

 functional group: group of atoms within a molecule that interacts in predictable ways with other molecules  E.g. hydroxyl groups are hydrophilic.

 hydrophilic: attracts water molecules.

Monomers and Polymers

 Some biomolecules may be composed of hundreds or even millions of atoms.

 monomer: small molecular unit that is the building block of a larger molecule  polymer: long chain of small molecular units (monomers)  Life's large molecules are classified into four main categories: carbohydrates, lipids, proteins, and nucleic acids.

Building and Breaking Polymers

 Each time a monomer is added to a chain, a water molecule is released, This is called a dehydration reaction because it involves removing (de-) water (hydro-).  Cells break bonds between monomers by adding water to them, the reverse of dehydration, This process is called a hydrolysis reaction because water (hydro-) is used to break down (-lysis) the polymer.

Activity 5.1

Concept Check 5.1

1. Draw a molecule that has a three-carbon skeleton and a hydroxyl group on the middle carbon. (Hint: The molecule's formula is C 3 H 8 O.) 2. Explain the connection between monomers and polymers.

3. What molecule is released during construction of a polymer? What is this reaction called?

4. Draw at least three ways in which five carbon atoms could be joined to make different carbon skeletons.

Carbohydrates provide fuel and building material. (Concept 5.2 ) page 95

Sugars

 carbohydrate: organic compound made of sugar molecules (Carbo hydrate)  Contains carbon, hydrogen, and oxygen in the ratio of 1 : 2 : 1. 1carbon: 1hydrogen: 1oxygen  Basic formula of CH 2 O. Most found in nature have a ring shape.

Sugars

Monosaccharide

 monosaccharide: sugar containing one sugar unit  Glucose, fructose, and galactose are examples of monosaccharides. (suffix -ose.)  E.g. Honey contains both glucose and fructose.

 Glucose exists in both straight-chain and ring-shaped forms.

 Used for energy, or stored as large carbohydrate, or used to make fat molecules.

Sugars

Disaccharides

 disaccharide: sugar containing two monosaccharides.

 Using the dehydration reaction, cells construct from two monosaccharides.  The most common disaccharide is sucrose =glucose + fructose.

 E.g. Plant sap (maple syrup) contains sucrose.  E.g. Table sugar is sucrose.

Polysaccharides

 polysaccharide: long polymer chain made up of simple sugar monomers  E.g

starch: polysaccharide in plant cells that consists entirely of glucose monomers .

 Humans and most other animals are also able to use plant starch as food by breaking it down within their digestive systems.

 Potatoes, rice, and corn are examples of foods rich in starch.

Polysaccharides

 glycogen: polysaccharide in animal cells that consists of many glucose monomers.

 In humans, most glycogen is stored as granules in liver and muscle cells. When the body needs energy, it breaks down these glycogen granules, releasing glucose.

 cellulose: polysaccharide consisting of glucose monomers that reinforces plant-cell walls Read last two paragraphs in 5.2

Figure 5-8 Glycogen, cellulose, and starch are three types of polysaccharides found in food. Though all three polymers are composed of the same monomer, glucose, the way the glucose monomers link together is different for each.

Activity 5.2

Concept Check 5.2

1. Explain the difference between a monosaccharide and a disaccharide. Give an example of each.

2. Compare and contrast starch, glycogen, and cellulose.

3. How do animals store excess glucose molecules?

Meet two Biochemists

Lipids include fats and steroids. (Concept 5.3 ) page 98 -list -Demo

Characteristics of Lipids

 lipid: one of a class of water-avoiding compounds  hydrophobic: avoids water molecules  lipids act as a boundary that surrounds and contains the aqueous (watery) contents of your cells.  lipids circulate in your body as chemical signals to cells.

 lipids known as fats store energy in your body.

Fats

 fat: organic compound consisting of a three-carbon backbone (glycerol) attached to three fatty acids  Some fats are solid at room temperature. Other fats called oils are liquids at room temperature.  In addition to storing energy for later use, fatty tissues cushion your organs and provide your body with insulation.

Fats

 saturated fat: fat in which all three fatty acid chains contain the maximum possible number of hydrogen atoms .

(Most animal fats, such as lard and butter, are saturated. They are solid at room temperature.)  unsaturated fat: fat with less than the maximum number of hydrogens in one or more of its fatty acid chains.

(The fats in fruits, vegetables, and fish are generally unsaturated, as are corn oil, olive oil, and other vegetable oils.)

Figure 5-9 Certain vegetable oils contain unsaturated fat molecules, which have at least one double bond in at least one of the fatty acid chains. In this case, the double bond is located about halfway along the bottom chain.

Steriods

 steroid: lipid molecule with four fused carbon rings.

 Steroids are classified as lipids because they are hydrophobic, but they are very different from fats in structure and function.  Some steroids circulate in your body as chemical signals. The steroids estrogen, a female sex hormone, and testosterone, a male sex hormone, function in this way.

Figure 5-10 The only difference in these two steroid hormones is the location of their functional groups. Yet, these two molecules contribute to major differences in the appearance and behavior of male and female mammals.

Steriods

 cholesterol: essential steroid molecule present in the plasma membranes of animal cells.

Activity 5.3

Concept Check 5.3

1. What property do lipids share?

2. What are the parts of a fat molecule?

3. Describe two ways that steroids differ from fats.

4. What does the term unsaturated fat on a food label mean?

-Finish Macromolecule Lab & concept check 5.3

-Online resources -Outline 5.4

Proteins perform most function in cells. (Concept 5.4 )

page 100

The functions of proteins.

 protein: a polymer constructed from a set of just 20 kinds of monomers called amino acids.

 For example: -hair, fur, muscles. -long-term nutrient storage.

-circulate in the blood and defend the body from harmful microorganisms.

-act as signals, conveying messages from one cell to another. -controls the chemical reactions in a cell.  Structure of proteins is key to understanding its function.