2.1 Molecules to Metabolism

Understandings Molecular biology explains living processes in terms of the

chemical substances involved. Carbon atoms can form four covalent bonds, allowing a

diversity of stable compounds to exist. Life is based on carbon compounds, including carbohydrates,

lipids, proteins, and nucleic acids. Metabolism is the web of all enzyme-catalyzed reactions in a

cell or organism. Anabolism is the synthesis of complex molecules from simpler

molecules, including the formation of macromolecules from monomers by condensation reactions.

Catabolism is the breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers.

Applications/Skills A: Urea as an example of a compound

that is produced by living organisms but can be artificially synthesized.

S: Drawing molecular diagrams of glucose, ribose, a saturated fatty acid, and a generalized amino acid.

S: Identification of biomolecules such as sugars, lipids, or amino acids from molecular diagrams.

GuidanceOnly the ring forms of D-ribose, alpha-D-glucose, and beta-D-glucose are expected in drawings.Sugars include monosaccharides and disaccharides.Only one saturated fat is expected, and its specific name is not necessary.The variable radical of amino acids can be shown as R. The structure of the individual R-groups does not need to be memorized. Students should be able to recognize from molecular diagrams the triglycerides, phospholipids, and steroids are lipids. Drawings of steroids are not expected.Proteins or parts of polypeptides should be recognized from molecular diagrams showing amino acids linked by polypeptide bonds.

Carbon

Carbon has 4 electrons in outer shell.

Carbon can form covalent bonds with as many as 4 other atoms (elements).

Usually with C, H, O or N.

Example:CH4(methane)

http://i3.cpcache.com/product/1389305943/periodic_table_carbon_tile_coaster.jpg?height=460&width=460&qv=90

http://winking-falcon.com/engineering%20web/2manufacturing/electronics/carbon.jpg

Macromolecules

Large organic molecules. Also called POLYMERS. Made up of smaller “building blocks” called MONOMERS. Examples:

1. Carbohydrates2. Lipids3. Proteins4. Nucleic acids (DNA and RNA)

http://bio1151b.nicerweb.net/Locked/media/ch05/05_07bStarch-L.jpg

Dehydration Synthesis

Also called “condensation reaction” Anabolic Forms polymers by combining monomers by removing a molecule of

water.HO HO HH

H2O

HO H

Hydrolysis

Separates monomers by adding a molecule of water Catabolic

HO H

H2O

HO HO HH

Metabolism

Sum of all chemical reaction in a cell or organism

Involves a variety of enzymes

http://academic.pgcc.edu/~kroberts/Lecture/Chapter%205/05-01_Metabolism_L.jpg

Molecule Monomer Subcategory Examples

Carbohydrates Monosaccharides Monosaccharides, disaccharides, polysaccharides

Glucose, fructose, lactose, starch, glycogen

Proteins Amino Acids Enzymes, antibodies, some hormones

Lipids Fatty acids w/ glycerol/phosphate group

Triglycerides, phospholipids, steroids

Adipose tissue, phospholipid bilayer, some hormones

Nucleic acids Nucleotides DNA, RNA, ATP

Structure of glucose and ribose

http://homebrewsake.com/wp-content/uploads/2010/04/glucose.gif

http://wps.prenhall.com/wps/media/objects/3085/3159329/blb2509/25-31a.jpg

Structure of a fatty acid

http://www.charleszaremba.com/images/triglycerides2.jpg

Structure of an amino acid

http://www.nutrientsreview.com/wp-content/uploads/2014/10/Amino-Acid-Structure.jpg

Homework

VocabMetabolismCatabolismAnabolismHydrolysisCondensation reactionVitalism

Other Challenge yourself #2 Exercises 1-3 Nature of science: Explain the idea of

vitalism. Describe why it is no longer accepted as a scientific theory.