Kategorier: Alle - bases - rna - dna - nucleotides

af Faith Stewart 4 år siden

244

Biological Macromolecules back up

Nucleic acids are fundamental for storing and transmitting genetic information in living organisms. DNA and RNA are two primary types of nucleic acids. DNA, known for its double-stranded helical structure, consists of a sugar-phosphate backbone with bases adenine, thymine, cytosine, and guanine.

Biological Macromolecules back up

Biological Macromolecules

Lipids

-a nonpolar compound that is made mostly of carbon and hydrogen

Steriods

-a lipid composed of four carbon rings

Cholesterol

-plays an important role in your body

-needs it to make hormones, Vitamin D and help aid in digestion





Hormones

Fats
Glycerol

-it has 3 carbon atoms, 8 hydrogen atoms, and 3 oxygen atoms

-the chemical structure of glycerol shows that each carbon atom is bonded to an -OH group







Triglycerol

-large source of energy, but more difficult to utilize than carbohydrates

-3 fatty acids linked to a glycerol molecule

3 Fatty Acids

-a hydrocarbon chain with a carboxyl functional group

Unsaturated

-double bonds in the hydrocarbon chains

-are usually liquid and from plant sources



Saturated

-only single bonds in the hydrocarbon chains

-tend to be solid at room temperature and from animal sourcs


Phospholipids

-a lipid that contains two fatty acid chains and a phosphate group bound to a glycerol

-polar, hydrophilic head

-nonpolar, hydrophobic tail

-the primary lipid of a cell membrane

Diacylglycerol

-consists of two fatty acid chains covalently bonded to a glycerol molecule through ester linkages

-2 possible forms exist, 1,2-diacylglycerols and 1,3-diacylglycerols




2 Fatty Acids

Carbohydrates

-a molecule that consists of carbon, oxygen, and hydrogen

Polysaccharides

-a molecule that contains many linked monosaccharides

-large source of energy

Glycogen
Starch
Cellulose

-is a molecule consisting of hundreds of carbon, hydrogen and oxygen atoms

-main substance in the walls of plant cells

-important in a humans diet as fibre






Oligosaccharides

-two or more monosaccharides join together by O-glycosidic bonds








Stachyose
Raffinose

-composed of galactose, glucose, and fructose

-can be found in vegetables and whole grains





Disaccharides

-two monosaccharides joined by a dehydration synthesis reaction

Maltose
Lactose
Sucrose

-a molecule composed of two monosaccharides

-produced natuarlly in plants

-common sugar







Monosaccharides

-the simplest form of a carbonhydrate

Galactose
Fructose
Glucose

-is a monosaccharide containing six carbon atoms

-found in fruits and plants









Nucleic Acids

-are the assembly instructions for all proteins in living organisms


RNA

-sugar-phosphate backbone

-4 bases (G,C,A,U)

-single-stranded

DNA

-sugar-phosphate backbone

-5' end has phosphate, 3' end has the sugar

-four bases projecting from the backbone (A,T,C,G)

-double-stranded

-strands run antiparallel to each other

-hydrogrn bonds form between complimentary bases on opposite strands (G forms 3 bonds with C, and A forms 2 bonds with T)

-twists into double-helical formation


Nucleotides

-are the buiding blocks of nucleic acids

-are liked together by a sinlge bridging phosphate group between the 5'-carbon of one sugar and the 3' -carbon of the next sugar

Phosphate Group

-a molecule containing one atom of phosphorus covalently bound to four oxygen residues

-relatively reactive molecules that form phophoester fonds by the interaction with hydroxyl groups






Pentose Sugar

-is a monosaccharide ("simple" sugar)

-has five carbon atoms






Deoxyribose

-found in DNA

-molecules bound to both a phosphate group and either a purine or a pyrimidine

-helps form the backbone of DNA molecules




Ribose

-found in RNA

-is a "normal" sugar, with one oxygen atom attached to each carbon atom


Nitragenous Base

-an organic molecule with a nitrogen atom that has the chemical properties of a base

-bonds nucleic acids together


ACGTU

-the nitrogenous bases in DNA are adenine (A), guanine (G), thymine (T), and cytosine (C)

-the nitrogenous bases in RNA are adenine (A), guanine (G), uracil (U), and cytosine (C)


ATP

-is a molecule that carries energy within the cells

-referred to energy currency of the cell

Proteins

-a large molecule consisting of many amino acid subunits

-joined by peptide bonds and folded into a specific three-dimensional shape

Amino Acids

-is a molecule containing a carboxyl group, an amino group and a side group (R group)

-the difference in R groups is what distinguishes amino acids from each other

-there are 20 different amino acids (meaning 20 different R groups)

Primary Structure

-unique linear sequence of amino acids in each polypeptide chain

-20^2= 400 combinations of two amino acids

-20^20 ..... virtually limitless number of combinations

Secondary Structure

-hydrogen bonding between different parts of the amino acid backbone creates two common secondary structures

Beta Sheet

-two or more segements of a polypeptide chain line up next to each other

-forming a sheet-like structure held together by hydrogen bonds







Alpha Helix

-in an a helix, the carbonyl of one amino acid is hydrogen bonded to the amino H (N-H) of an amino acid that has four down the chain

-coiled structure in filamentous and transmembrane proteins





Tertiary Structure

-3 dimensional shape due to intermolecular reactions between R- groups


Quaternary Structure

-many proteins are composed of two or more polypeptides joined together

-held together by the same types of bonds as in the tertiary structure