II. How does synthesis provide important organic macromolecules using six essential elements?

A. Carbohydrates1. Carbohydrates are organic compounds

made of carbon, hydrogen, and oxygen in a 1:2:1 ratio. The subunit (monomer) is called a monosaccharide. Many monosaccharides bond together forming a larger carbohydrate chain called a polysaccharide.

a. In plants the monosaccharide called glucose (C6H12O6) bonds with other glucose molecules again and again to form starch or cellulose. The plant can use starch as food (like the “white” or a potato) and cellulose to build the stem and leaves.

b. In animals excess glucose bond together to form a compound (similar to starch) called glycogen which is used for short-term energy storage. Glycogen is found in the liver and muscles.

Examples:

Glucose - monosaccharide -simple sugar

Sucrose – disaccharide – table sugar

Starch – polysaccharide - corn

2. Functions of carbohydrates a. Energy is released when carbohydrates are digested. This is because glucose is used for cellular respiration.

i. Monosaccharides (simple sugars) provide an immediate energy source

ii. Starch and glycogen are considered short term energy sources because these chemicals can be broken down over a period of minutes, hours or days to provide glucose for energy.

b. Some carbohydrates are very stable and can be used for structure and support in the cell and body (cellulose in the cell wall of plant cells).

c. Carbohydrate chains on the surface of cell membranes are used as identifiers (like name tags).

II. How does synthesis provide important organic macromolecules using six essential elements?

B. Lipids 1. There are several types of lipids, but all

contain subunits of glycerol and fatty acids made of carbon, hydrogen, and oxygen. These combine to make a very large molecule (macromolecule). Unlike a carbohydrate the smaller units do not link together to form a chemical chain, but combine in the shape of an “E”.

a. Fats can be saturated (usually solid at room temperature) or unsaturated (usually liquid).

b. Phospholipids also contain a phosphate group and make up most of the cell membrane.

c. Steroids are lipid rings and help regulate the organism through cell communication (act as hormones)

2. Functions of lipidsa. Because of the numerous bonds and the way the body

stores lipids, they can be used as very long-term (weeks, months) energy sources.

Ex. Bears accumulate a layer of fat before winter

(when food will be less available)

b. Fats stored in the body act as insulation and protection for internal organs.

c. Some hormones are composed of lipids (steroids).

II. How does synthesis provide important organic macromolecules using six essential elements?

C. Nucleic Acids1. Nucleotides are compounds

made up of carbon, hydrogen, oxygen, nitrogen and phosphorus. Many nucleotides bond together to make up a long chain called a nucleic acid. There are two basic types of nucleic acids:

a. DNA is a double chain of nucleotides found in all living cells.

b. RNA is a single chain of nucleotides that provides the structures needed for the cell to make proteins.

2. Functions of nucleic acidsa. DNA makes up the genes. Genes are used to

pass traits from parent to offspring. Genes determine traits.

b. DNA controls cellular activities by controlling the production of proteins in response to hormones and other cellular signals.

c. RNA is used in the production of proteins.

II. How does synthesis provide important organic macromolecules using six essential elements?

D. Proteins - Functions of Protein1. All six essential elements may

be used in the production of small subunits called amino acids. There are 20 different amino acids, each with a specific side chain of chemicals. Amino acids bond to other amino acids to form a long chain called a protein. These chains of amino acids fold into a particular shape. The shape of a protein will determine its function. If a protein denatures (loses its shape) it can no longer function.

a. Hemoglobin is a protein shaped to hold oxygen for transport through the bloodstream.

b. A group of proteins called enzymes are shaped to fit and react with specific molecules.

2. Functions of proteins – the basic building materials for lifea. Some proteins, called pigments, absorb and

reflect light. They also create color by reflecting light. Ex. Chlorophyll absorbs light to gather energy for photosynthesis, and reflects the color green

b. Some proteins are constructed by cells to bind with and inactivate foreign particles in the body. These are called antibodies.

c. Proteins may form structures in an organism – such as keratin (a protein) in hair and nails.

d. Some proteins are used for transport through the cell membrane or in the bloodstream (ex. hemoglobin)

e. Some proteins are used for communication between cells. These may be hormones (insulin) or neurotransmitters. Insulin is secreted by the pancreas and is required by the cells of the body in order for them to remove and use glucose from the blood. Insulin can be used to treat diabetes.

f. Enzymes (a special class of protein) act to speed up chemical reactions.