Biology Standard 1 2 Describe the basic molecular

Biology Standard 1. 2 Describe the basic molecular structures and primary functions of the four major categories of organic molecules (carbohydrates, lipids, proteins, nucleic acids).

Essential Questions 1. What does organic mean? 2. Identify organic molecules by structure. 3. Identify organic molecules by function.

Essential Vocabulary organic molecule, organic compound, carbohydrate, lipid, nucleic acid, protein, monomer, polymer, monosaccharide, polysaccharide, amino acid, peptide, fatty acids, fats, steroids, unsaturated, wax, nucleotide, polynucleotide, macromolecules

Organic Molecules Living organisms are composed of inorganic and organic molecules. The chemistry of carbon accounts for the chemistry of organic molecules (Organic Chemistry). Organic molecules are macromolecules.

Learning Check What are the six elements essential to life? C, H, N, O, P, S

Macromolecules are polymers that are formed from smaller building blocks called monomers. Macromolecule Monomer Polymer carbohydrate monosaccharides polysaccharide protein amino acid polypeptide nucleic acid nucleotide polynucleotide

Learning Check Fill in the blanks: ______ are made of smaller parts called _______. Polymers are made of smaller parts called monomers

Carbohydrates serve as quick energy and shortterm energy storage. They play a structural role in plants, bacteria, and insects. Monomers of carbohydrates are the monosaccharides: glucose fructose galactose

Learning Check What is the function of carbohydrates? A. Source of energy B. Structural components of living things C. Both A and B

The structure of glucose

A disaccharide is made by linking two monosaccharides together. glucose + fructose = sucrose glucose + galactose = lactose

Larger polysaccharides are made from linking many monosaccharides together. Starch - a polysaccharide composed of glucose. - predominantly made by plants.

Glycogen - a polysaccharide made of glucose - predominantly made by animals

Cellulose - a structural polysaccharide found in the cell wall of plant cells. - composed of glucose monomers (monosaccharides). - but because of the way the glucose monomers are linked together, we and most animals cannot digest cellulose. - in our diets, we often refer to cellulose as fiber.

Learning Check A polysaccharide is composed of smaller units called A. B. C. D. Amino acids Nucleotide Monosaccharides Fatty acids

Lipids serve as long-term energy stores in cells, form membranes, serve as hormones and make waterproof coverings Lipids do not dissolve (insoluble) in water (hydrophobic). Fats and oils are formed from a glycerol molecule and three fatty acid molecules. (triglyceride)

Learning Check What does the term ‘hydrophobic’ mean? A. Easily dissolves in water B. Does not dissolve in water C. Afraid of hydrogen

Structure of Triglycerides

Fatty acids are long chains of carbons Fatty acids may be saturated fatty acids or unsaturated fatty acids. Saturated- has as many hydrogens as possible (bad fats) Unsaturatedhas less hydrogens (good fats)

Learning Check Which kind of fats are better for you? A. Saturated B. Unsaturated

Some lipids are phospholipids that form cell membranes.

Phospholipids are a major component of cell membranes. Phospholipids control what enters and leaves the cell

Steroids Another type of lipid - are found in cell membranes - are our hormones- act as chemical messengers for the human body.

Learning Check What is the function of steroids? A. Increase your size B. Make sports more exciting C. Act as chemical messengers in the body

Types of Lipids • • • Fats (saturated) stores energy, insulation Oils (unsaturated) stores energy Wax waterproof coverings Steroids chemical messengers Phospholipids cell membranes

Proteins perform many functions in cells and living things. - Serve as structural proteins in living things (muscles and bone). - Act as enzymes to speed up chemical reactions, like digestion of food. - Act as antibodies which fight diseases.

• Serve as transport carriers in the body (Hemoglobin carries oxygen in blood) • Allow materials to cross cell membranes. • Proteins are the expression of our genes.

Proteins are made of the monomers amino acids. There are 20 amino acids.

Learning Check What is the monomer of a protein? a. Nucleotide b. Monosaccharide c. Amino acid

Peptide bonds join amino acids to make the polymer polypeptides.

Proteins have levels of organization. Proteins can be denatured (broken apart).

Nucleic Acids Nucleic acids store and transmit (send) genetic information. Nucleic acids are made of monomers of nucleotides.

Learning Check What is the monomer of a nucleic acid? a. Nucleotide b. Amino acid c. Monosaccharide

• Large nucleic acids are polymers called polynucleotides. • Examples of nucleic acids include Deoxyribonucleic Acid (DNA) and Ribonucleic Acid (RNA).

DNA is double-stranded, with complementary base pairing.

Some nucleotides also perform functions in cells. Adenosine triphosphate (ATP) is the energy currency of cells.

Summary Organic molecules contain carbon. Four organic molecules found in living things are: Carbohydrates Lipids Proteins Nucleic Acids