Biology Ch5

Large Molecules

• Carbohydrates
• Proteins
• Nucleic Acids
• Lipids - not a macromolecule group

• Greek - Polys (many) and meris (part) Many parts
• Long molecule consisting of many similar or identical builing blocks linked by covalent bonds (train consists of cars)

Smaller molecules that often make up the building blocks of polymers

• Building
• also called a condensation reaction or a dehydration reaction
• Two monomers covalently bonded to one another thorugh the loss of a water molcule
• Both momomers contribute part of the water molecule that is lost (one contributes -OH and one -H)
• Energy is used
• 1 molecule of water is realeased
• Extra Energy is stored in the bonds
• Some energy is lost as heat

• Breaking Down
• Greek hydro (water) lysis (break) To break down using water
• Bonds are broken by the attition of a water molecule and a polymer separates into monomers
• 1 water molecule is used
• 1 bond is broken
• entergy is relased

Charbohydrates -Sugars and polymers of sugars

• simple sugars
• Glucose is the most common -C₆H₁₂O₂
• Fructose is a isomer of glucose
• A sugar molecule has a corbonyl group and multible hydroxyl groups. Depending on location of carbonyl group the sugar is either aldose (aldehyde sugar) or ketose (ketone sugar)

• Size of the carbon skeleton - ranges from three to seven carbons long
• Glucose, fructose have six carbons are called hexoses
• three carbon sugars are called trioses
• five carbon sugars are called pentoses

• double sugars, two monosaccharides joined by glycosidic linkage ( a covalent bond by dehydration synthesis)
• Maltose, Sucrose (table sugar), lactose

Macromolecules, polymenrs composed of many sugars joined by glycosidic linkage

• Storage Polysaccharides
• Structure Polysaccharides

• Plants store surplus glucose as a polysaccharide called Starch
• Animals store a polysacchride called Glycogen - stored as granules in the liver and muscles

• Organisms build strong materials from structural polysaccharides
• Plants - Cellulose (polysaccharide) is the major component of the tough walls that enclose plant cells- insoluable fiber **Cellulose is the most abundant organic compound on earth
• Animals - Chitin - exoskeleton of insects and crustaceans

• Not Macromolecules
• Mostly Hydrophobic - no monomers
• Fats, Steroids, Phospholipids, waxes

• Lipid - hydrophobic - not a macromolecule
• Fats are storage for animals - can store twice as much potential energy than other storage
• A fat is formed by a glycerol (alcohol w/ 3 carbons-each with a hydroxly group) with three fatty acids (Long carbon chains -16 to 18 carbons- with a carboxyl group (acid) - triglyceride
• (Carbon chain surrounded by Hydrogen)
• 

• Normally solid at room temperature
• Animal Fat - bacon fat, butter, lard
• Hydrocarbons - where there are no double bonds between carbons then as many hydrogen atoms as possible are bonded to the carbon skeleton - saturated with hydrogen
• The "tails" of fat have no double bonds are very flaxible - can be tightly packed (solid)

• Oils - liquid at room temperature
• Hydrocarbon - has one or more double carbon bonds - kinks where Cis double bonds forms -
• tails are not able to be tightly packed together so stays as liquid

• Unsaturated fats are atrifically pumped full of hydrogen atoms to make them saturated. This process makes saturated fats and unsaturated fats with a trans double bond.
• Saturated and Trans fats cause plaque (deposits within the wall off a blood vessel that cause invard bulges and decreases blood flow)

• Make up the cell membrane - essential for cells
• One glycerol (alcohol w/3 carbons each has a hydroxyl group) attached to two fatty acids (hydrocarbon with a carboxyl group) third hydroxyl group is attached to a phosphate group
• Polar heads are hydrophyllic
• Hydrocarbon tails are hydrophobic
• Form a bilayer with head out and tails that is essential for call membrane
• 

• Lipid - not a macromolecule - sex hormones
• Carbon skeleton consisting of 4 fused rings
• Cholesterol is an essential steroid in the liver that synthesizes other steroids (sex hormones)
• Secondary sexual Characteristics - artifical steroids cause wrong sex hormones to be produced - women grow hair on face, mens testicles shrink

• Macromolecule - can not be constructed without amino acids
• 75,000 proteins in our body are made from different combonations of 20 Amino Acids. Every living thing has 20 amino acids.
• Amino Acids are joined by Peptide Bonds to form Polypeptides- Peptide bonds only work for Amino Acids - the carboxyl groups of one Amino Acid joins the amino group of amother through dehydration systhesis
• Proteins consist of one or more polypeptides twisted, folded, and coiled into a molecule of unique shape.

• Amino Acids are joined by Peptide Bonds to form Polypeptides- Peptide
• bonds only work for Amino Acids - the carboxyl groups of one Amino Acid
• joins the amino group of amother through dehydration systhesis

Polymers of amino acids. A protein is made of one or more polypeptide chains twisted, folded, and coiled into molecule of unique shape

• globular (roughly spherical)
• fibrous (long fibers)

Form equals function. Proteins are polypeptides that are folded, twisted and coiled into specific shapes for specific purposes

• 1)Primary structure - Unique amino acid sequence (amino end and carboxyl end) - problems if not in the right order (cicle cell anemia)
• 2)Secondary structure - pleating, coiling and folding aided by Chaperonin - surrounds and protects the proteins that are folding. Misfolding results in Alzheimers, Parkinsons
• 3)Tertiary structure - 3D shape - hydrophobic interations - as a polypeptide folds amino acids with hydrophobic side chains end up clusted in the middle. Mad cow disease is caused by misshapen tertiary structure
• 4)Quarternary - 2 or more polypeptides (subunit) combine to form a unit

• When a protein is unraveled or loses its native shape - some are irreversible. The denatured protein is biologically inactive.
• 1)Extreme changes in temperature - ex. Ovalbumin (egg whites) when cooked
• 2)Extreme changes in pH - body pH over 7.8 results in death
• 3)Extreme changes in salt concentration - dehydration = high salt concentration

• 1) Enzymes - most important - speed up chemical reacions -digestive enzymes
• 2) Structural proteins - support - hair & tentons
• 3) Contractile proteins - movement - muscles
• 4) Defense proteins - protect against disease - antibodies combat bacteria and viruses
• 5) Signal proteins - Hormones - insulin (a hormone secreted by the pancreas regulates sugar in the body)
• 6) Receptor proteins - in the cell membrane - can detect chemical signals sent by other cells
• 7) Transport proteins - hemoglobin transports oxygen to all parts of body
• 8) Storage proteins - storage of amino acids - ovalbumin (egg white) is amino acid source for the embryo

variable group or side chain attached to an amino acid that differs with each amino acid

• Macromolecule - enables living organisms to reproduce their complex components from one generation to the next (DNA & RNA)
• Its monomer is a nucleotide - polymers are polynucleotides

• Nobel prize for chemistry 1954
• Nobel prize for peace 1963
• Only person ever to be awarded two unshared nobel prizes
• Described alpha helix and pleated sheet in seconday protein structure

Watson & Crick given nobel prize for structure of DNA

unit of inheritance that programs the amino acid sequence of a polypeptide

• Deoxyribonucleic acid
• genetic material that organisms inherit from their parents
• *DNA provides directions for its own replication
• *DNA directs RNA sysntesis and, through RNA, contols protein synthesis
• 

• Nucleotide is the building blocks of polynucleotides - Nucleic Acids
• 1)Nitrogenous Base - pyrimadines or purine
• 2)Pentose (5 carbon) sugar - ribose for RNA and deoxyribose for DNA
• 3)Phosphate group
• The porton of this group without the phosphate group is called a nucleoside (nitrogenous base and sugar)

• used to build nucleotides (used to build nucleic acid)
• 1) pyrimidine - six-membered ring of carbon and nitrogen atoms
• a) cytosine (C)
• b) thymine (T)
• c) Uracil (U)
• 2) pruines - larger, six membered ring fused to a five membered ring
• a) Adenine (A)
• b) Guanine (G)

sugars in a nitrogenous base are numbered - second carbon in a sugar rings is 2' (2prime) and the carbon that sticks up from the ring is a 5' carbon

• a phosphate group that links the sugars of two nucleotides (backbone with a repeating pattern of sugar-phosphate units)
• the two end are distinctly different - one end has a phosphate attached to a 5' carbon and the other end has a hydroxly group on a 3' carbon
• In DNA sugar-phosphate backbone on the outside with nitrogenous bases paired on the inside (links between the double helix)
• 5' - Phosphate group
• 3' - Hydroxly group

• DNA
• A - T Adenine - Thymine
• T - A Thymine - Adenine
• C - G Cytosine - Guanine
• G - C Guanine - Cytosine

• RNA
• A - U Adenine - Urasil
• U - A Urasil - Adenine
• C - G Cytosine - Guanine
• G - C Guanine - Cytosine

• Process by which DNA synthesizes RNA
• DNA is the boss

• Replication - Mitosis - process by which a cell separates DNA into two identical sets
• Replication is caused by
• Disease
• Damage
• Death
• Growth

• messanger RNA (synthesized in the nucleus)
• transfer RNA (fouund in the cytoplasm)
• ribosomal RNA (found in the nucleolus)