Slide 1 Chapter 3 The Molecules of Life Slide 2 State Standards Standard 1.h. Standard 5.a. Standard 4.e. Slide 3 Organic Molecules A cell is mostly water. The rest of the cell consists mostly of carbonbased molecules organic compounds. Life s diversity results from Organic chemistry is the study of carbon compounds.
Slide 4 Carbon Chemistry Carbon is a versatile atom. It has 4 electrons in an outer shell that holds eight. Carbon can share its electrons with other atoms Carbon can use its bonds to Attach to other carbons. Form an endless diversity of carbon skeletons. Slide 5 Slide 6 The simplest organic compounds are hydrocarbons. These are organic molecules containing Composed of a carbon skeleton with The simplest hydrocarbon is methane.
Slide 7 Slide 8 Larger hydrocarbons Are the main molecules in the gasoline we burn in our cars. The hydrocarbons of fat molecules provide energy for our bodies. Slide 9 The unique properties of a organic compound depend not only on its carbon skeleton but also on the atoms attached to the skeleton. These atoms are called functional groups. The functional groups of an organic compound participate in chemical reactions.
Slide 10 Slide 11 Hydrocarbon Practice Directions: Draw the following 5 carbon hydrocarbons: 1. Unbranched b. Why does each carbon bond to 4 other atoms? 2. With a double bond b. What is the molecular formula of this hydrocarbon? 3. Branched with no double bonds b. What is the molecular formula? Ringed with one double bond b. How many hydrogen atoms are in this molecule? Slide 12 Hydrocarbon Practice Identify the functional group or groups in each molecule. 1. 4. 2. 5. 3. Copyright 2007 Pearson Education Inc., publishing as Pearson Benjamin Cummings
Slide 13 Giant Molecules from Smaller Building Blocks Many of life s molecules are gigantic. Biologists call them macromolecules. Examples: DNA, carbohydrates Most macromolecules are polymers. Polymers are made by stringing together many smaller molecules called monomers. A huge number of different polymers can be made from a small number of monomers. Slide 14 Cells link monomers to form polymers by dehydration synthesis Slide 15 Polymers are broken down to monomer by the reverse process, hydrolysis
Slide 16 State whether the statement is describing dehydration synthesis or hydrolysis. 1. Connects monomers to form a polymer. 2. Produces water as a byproduct. 3. Breaks up polymers, forming monomers. 4. Water is used to break bonds between monomers. 5. Joins amino acids to form a protein. 6. Glycerol and fatty acids combine to form a fat. 7. Occurs when polysaccharides are digested to form monosaccharides. 8. H and OH groups form water. 9. Nucleic acid breaks up to form nucleotides. 10. Water breaks up. Slide 17 Biological Molecules There are four categories of large molecules in cells: Carbohydrates Lipids Proteins Nucleic acids Slide 18 Carbohydrates Carbohydrates include Simple sugar molecules such as glucose in soft drinks Large polysaccharides such as starch molecules in pasta and potatoes
Slide 19 Carbohydrates The functions of carbohydrates include Provide energy for cellular work Short term storage of energy Building material to form plant bodies Carbon skeleton can be used to produce other organic compounds Slide 20 Monomers of carbohydrates The monomers of carbohydrates are the monosaccharides (simple sugars) Slide 21 Monosaccharides Monosaccharides are simple sugars. Examples: glucose, fructose They are the source of energy for cellular work. Their carbon skeleton is used to produce other organic compounds
Slide 22 Disaccharides A disaccharide is a double sugar It is made from two monosaccharides. Examples include: sucrose, lactose, maltose Slide 23 Cells link simple sugars to form disaccharides Monosaccharides can join to form disaccharides by a dehydration synthesis reaction. Slide 24 Polysaccharides
Slide 25 Polysaccharides Polysaccharides are complex sugars They are long chains of monosaccharides linked together by dehydration synthesis reactions. Examples include: starch, glycogen, cellulose Slide 26 Lipids Lipids are composed mainly of carbon and hydrogen They are grouped together because they are hydrophobic. Functions are: long term energy storage, hormones (chemical messengers) Examples: fats, steroids, phospholipids, waxes Slide 27 Fats Fats are lipids whose main function is long term energy storage They are also called triglycerides Fats perform essential functions in the human body: Long term energy storage Cushioning Insulation
Slide 28 Fats A triglyceride is a combination of glycerol and three fatty acid. Slide 29 Fatty acids can be saturated or unsaturated Slide 30 Healthy fats Not all fats are unhealthy. Some fats perform important functions in the body and are essential to a healthy diet Example: omega 3 fats found in some fish
Slide 31 Steroids Slide 32 Steroids Steroids are very different from fats in structure and function. The carbon skeleton is bent to form four fused rings. Cholesterol is the base steroid from which your body produces other steroids Example: sex hormones Slide 33 Anabolic steroids are usually synthetic forms of testosterone. Some athletes use them to build up their muscles quickly. However, these substances can pose serious health risks. Anabolic steroids
Slide 34 Phospholipids and Waxes Phospholipids are a major component of cell membranes. Waxes form waterproof coatings. Slide 35 Proteins Proteins perform most of the tasks the body needs to function This includes: enzymes transport hormones structural components antibodies contractile Slide 36 Proteins The building blocks of proteins are amino acids. There are 20 different amino acids. Each amino acids consists of A central carbon atom bonded to 4 covalent partners A side group that is different for each of the 20 amino acids.
Slide 37 Proteins Cells link amino acids together by dehydration synthesis reactions. The resulting bond between them is called a peptide bond. Slide 38 Your body has tens of thousands of different kinds of proteins The diversity of proteins Proteins differ in is based on its primary The different structure arrangements of the the specific sequence of amino acids amino acids The number of amino acids they contain Slide 39 A slight change in the primary structure of a protein affects its ability to function. The substitution of one amino acid for another in hemoglobin causes sickle cell disease.
Slide 40 Levels of Protein Structure Slide 41 Protein Structure A protein s shape determines its function. The shape of a protein is sensitive to the surrounding environment. Unfavorable temperature and ph changes can cause a protein to unravel, lose its shape and its function. This is called denaturation Slide 42 Nucleic Acids Nucleic acids are information storage molecules. They provide the directions for building proteins. They ultimately control the life of a cell. There are two types of nucleic acids: DNA, deoxyribonucleic acid RNA, ribonucleic acid
Slide 43 Nucleic Acids The monomers of nucleic acids are nucleotides. Each nucleotide is composed of a sugar, a phosphate group, and a nitrogenous base. Slide 44 Nucleic Acids Each DNA nucleotide has one of the following bases: Adenine (A) Guanine (G) Thymine (T) Cytosine (C) Slide 45 Nucleic Acids Nucleotides are linked into long chains. A sugar to phosphate backbone joins the nucleotides together.
Slide 46 The Structure of DNA The sugar in DNA is dexoyribose. The two strands of DNA join together to from a double helix. The sequence of the bases in DNA carries genetic information. Slide 47 DNA Provides the Instructions to Make a Protein The genetic instructions in DNA are used to produce the primary structure of a protein. Slide 48 Structure of RNA RNA is different from DNA Its sugar is ribose It has the base uracil (U) instead of thymine (T) It is single stranded
Slide 49 ATP The Cell s Energy ATP provides the energy needed for almost all cell and body activities. Slide 50 ATP The Cell s Energy ATP is composed of: a ribose sugar the base adenine 3 phosphate groups Potential energy is stored in the covalent bonds between the phosphate groups Slide 51 ATP The Cell s Energy Energy When the bond joining the 2 nd and 3 rd phosphate group is broken the stored energy is released and is used by the cell to do work.
1. 4. 2. 5. 3.
State whether the statement is describing dehydration synthesis or hydrolysis. 1. Connects monomers to form a polymer. 2. Produces water as a by product. 3. Breaks up polymers, forming monomers. 4. Water is used to break bonds between monomers. 5. Joins amino acids to form a protein. 6. Glycerol and fatty acids combine to form a fat. 7. Occurs when polysaccharides are digested to form monosaccharides. 8. H and OH groups form water. 9. Nucleic acid breaks up to form nucleotides. 10. Water breaks up.