Chapter 3-Cell Processes and Energy Section 1- Chemical compounds in cells

Elements and Compounds You may not realize it, but air is a mixture of gases Gases include both elements and compounds Three gases in the air are oxygen, nitrogen, and carbon dioxide

Elements Oxygen and nitrogen are examples of elements Element- any substance that can not be broken down into simpler substances Atom- smallest unit of an element Elements are made up of only one type of atom Elements found in living things are carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur

Compounds Carbon dioxide is a compound, made up of the elements carbon and oxygen Compound- when two or more elements combine chemically Most elements in living things occur in the forms of compounds Molecule- the smallest unit of any compound Ex- molecule of carbon consists of one carbon atom and two oxygen atoms

Which is water- an element or a compound? Why? It contains two elements- oxygen and water that are chemically combined

Compound Chemical called Water Like carbon dioxide water is a compound Each water molecule is made up of two hydrogen atoms and one oxygen atom Water makes up two thirds of your body

Water plays an important role in cells -1.most chemical reactions within cells could not take place without water 2. Dissolves chemicals cells needs -3.helps keep their size and shape -4.Keeps the temperature of cells from changing rapidly

Organic and Inorganic Compounds Many compounds in living things contain the element carbon Organic compounds- compounds that contain carbon Inorganic compound- compounds that do not contain carbon Ex- water, sodium chloride (table salt)

DO NOW What is the difference between an organic and inorganic compound? How does water play an important role in our cells?

Carbohydrates Carbohydrates, lipids, proteins, and nucleic acids are important groups of organic compounds in living things Carbohydrate- energy rich organic compound. Composed of the elements carbon, hydrogen, and oxygen Ex- sugars and starches

Sugars are produced during the food making process that takes place in plants Sugar molecules can combine forming larger molecules called starches or complex carbohydrates Plant cells store the excess energy in molecules of starch Many foods that come from plants that contain starch Ex- potatoes, pasta, rice, and bread

When you eat these foods, your body breaks down the starch in glucose Glucose- sugar your cells use to produce energy Carbohydrates are an important component of some cell parts Ex- Cellulose found in the cell wall of plants is type of carbohydrate -Also in cell membrane

Lipids Lipids- fats, oils, and waxes -energy rich organic compounds -contain even more energy than carbohydrates Cells store energy in lipids for later use. Ex- bear hibernates in the winter, lives on the energy stored in fat Cell membranes are made mostly of lipids

Proteins Proteins- large organic molecules made of carbon, hydrogen, oxygen, nitrogen, and some cases sulfur. Ex- Foods high in protein- meat, eggs, fish, nuts, and beans

Structure of Proteins Amino acids-protein molecules 20 common amino acids Cells can combine them in different ways to form thousands of different proteins The kind of amino acid and the order it links together determines the type of protein that forms. Ex- Alphabet- 26 letters can form thousands of different words

Functions of Proteins Much of the structure of cells is made up of proteins. Ex-parts of cell membranes and cell organelles The protein known as enzymes perform important functions in the chemical reaction that take place in cells Enzymes-type of protein that speeds up a chemical reaction in living things.

Enzymes-type of protein that speeds up a chemical reaction in living things. Without enzymes, many chemical reactions that are necessary for life would either take too long or not happen at all. Ex- enzymes in your salvia speed up the digestion of food by breaking down the starches into sugars in your mouth.

What elements make up proteins? Carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur What kinds of molecules make up proteins? Amino acids How are proteins used in living things? Part of cell membranes and organelles, enzymes speed up chemical reactions What are some examples of foods that are proteins?

Nucleic Acids Nucleic acids-very log organic molecules made of carbon, oxygen, hydrogen, nitrogen, and phosphorus -Contain instructions that cells need to carry out all the functions of life -2 type of nucleic acids- DNA and RNA

DNA- genetic material that carries information about an organism and is passed from parent to offspring -found in the chromatin -directs all the cell’s functions RNA- plays an important role in the production of proteins -found in the cytoplasm and the nucleus

What is DNA? Genetic material that carries information about an organism and that is passed from parent to offspring What does RNA do? Important role in the production of protein

Why are nucleic acids important to all cells in the body? They contain instructions that cells need to carry out all the functions of life How is RNA related to the structure of an organism? RNA is an important in the production of proteins, which make up much the structure of cells