Section 4 – pg 316 Life with Carbon Chapter 8 Section 4 – pg 316 Life with Carbon

Pg 317 The four classes of organic compounds required by living things are carbohydrates, proteins, lipids, and nucleic acids Carbohydrates, proteins, and lipids are nutrients Nutrients: substances that provide the energy and raw materials the body needs to grow, repair worn parts, and function properly

Pg 317 Carbohydrates Carbohydrate: an energy-rich organic compound made of the elements carbon, hydrogen and oxygen Name means carbon combined with water

Simple Carbohydrates The simplest carbohydrates are sugars Pg 317 Glucose: C6H12O6 Sometimes called blood sugar because the body circulates glucose to all body parts through blood Sucrose: C12H22O11 White sugar used in cookies, candies and soda Is more complex than glucose

Complex Carbohydrates Pg 318 Complex Carbohydrates Complex Carbohydrate: a polymer made of smaller molecules that are simple carbohydrates bonded to one another Starch and Cellulose are built from glucose but the arrangements are different

Pg 318 Starch Starch: plants use this form of carbohydrate to store energy Found in bread, cereal, pasta, rice and potatoes When we digest starch we break it down into the individual glucose molecules The energy released by breaking down starch allows the body to carry out life functions

Cellulose Cellulose: used by plants to build strong stems and roots Pg 318 Cellulose Cellulose: used by plants to build strong stems and roots Found in fruits and vegetables Our bodies cannot break down cellulose so passes through undigested Also called fiber

Proteins Your muscles, hair, skin and fingernails are made of proteins Pg 319 Proteins Your muscles, hair, skin and fingernails are made of proteins A bird’s feathers, a spider’s web, a fish’s scales and the horn of a rhino are also made of proteins

Chains of Amino Acids Pg 319 Proteins are polymers formed from combinations of monomers called amino acids There are 20 kinds of amino acids When different sequences of amino acids are linked together different proteins are made Amino Acid: acid comes from the carboxyl group and the amino comes from the NH2

Food Proteins Become Your Proteins Pg 319 The body uses proteins from food to build and repair body parts and to regulate cell activities When digested proteins are broken into amino acids which can then be reassembled Sources of protein: meat, fish, eggs, milk, milk products, nuts and beans

Pg 320 Lipids Lipids: energy-rich compounds made of carbon, oxygen, and hydrogen that release twice as much energy as carbohydrates Lipids mix poorly with water

Pg 320 Fats and Oils Fats are found in food such as meat, butter and cheese Oils are found in foods such as corn, sunflower seeds, peanuts and olives Oils and fats have the same basic structure: made from three fatty acids and an alcohol named glycerol Fats are solid at room temp, but oils are liquid at room temp

Saturated fats have no double bonds between carbon atoms Pg 320 Saturated fats have no double bonds between carbon atoms Unsaturated fats are found in oils Monounsaturated fats have fatty acids with one double bond Polyunsaturated oil have fatty acids with many double bonds

Cholesterol Cholesterol: a waxy substance found in animal cells Pg 320 Your body needs cholesterol to build cell structures and to form compounds that serve as chemical messengers Cholesterol is not a source of energy Your body can make cholesterol from other nutrients but cholesterol is also found in food from animals such as meat, cheese and eggs Too much cholesterol in blood can contribute to heart disease

Pg 321 Nucleic Acids Nucleic Acids: very large organic molecules made up of carbon, oxygen, hydrogen, nitrogen, and phosphorus DNA: deoxyribonucleic acid RNA: ribonucleic acid

Pg 322 Nucleotides DNA and RNA are made of different kinds of small molecules connected in a pattern Made of nucleotides

Pg 322 DNA and Proteins Living things differ from one another because their DNA, and therefore their proteins, differ from one another The cells in a hummingbird grow and function differently from the cells in a flower or in you

Pg 322 Other Nutrients Living organisms are made of molecules consisting largely of carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur The molecules that make up organisms are usually large molecules, such as DNA, proteins, carbohydrates and fats Organisms require water, vitamins, minerals, and salts to support the functioning of large molecules

Pg 322 Water Water makes up most of your body’s fluids, including about 90% of the fluid in your blood Nutrients and other important substances are dissolved in the watery part of blood and carried throughout the body

Pg 323 Vitamins Vitamins: organic compounds that serve as helper molecules in a variety of chemical reactions in your body Vitamin C: important for keeping skin and gums healthy Vitamin D: helps your bones and teeth develop and stay strong

Minerals Minerals: elements in the form of ions needed by your body Pg 323 Minerals Minerals: elements in the form of ions needed by your body Minerals are not organic compounds Calcium, iron, iodine, sodium and potassium

Salts Salts are ionic compounds found in your body as dissolved ions Pg 323 Salts Salts are ionic compounds found in your body as dissolved ions Sodium Chloride: help in the contraction of muscles and in the transmission of messages through nerves Other salts are vital to the healthy growth of bones and teeth and keeping blood pH balanced

Chapter 8 Section 4 Homework – pg 323

1A. What are the four main classes of organic compounds required by living things?

1B. To what class of organic compounds does each of the following belong: glucose- RNA- cholesterol- cellulose- oil-

1C. How is each class of organic compounds used by the body?

1D. Compare the building blocks found in complex carbohydrates with those found in proteins.

2A. What nutrients help support the functioning of large molecules in organisms?

2B. Why does your body need water to survive?

2C. How do vitamins and salts differ?