bio 221 lab water and organic molecules

water is a polar molecule why?

water is polar due to having both positive and negative charges. oxygen is negative, hydrogen is positive.

what is molarity?

numbers of moles of a solute dissolved in a liter of solution.

protons vs electrons what one is positive and what one is negative?

protons is positive, electrons are negative. fact to know electrons have kinetic energy.

valance electrons

The electrons in the outermost shell of an atom

atomic number

the number of protons in an atom

what is atomic mass measured in?

measures in units called Dalton's (DA)

what make up a molecule?

two or more molecules bonded together.

what is a compound?

a molecule composed of two or more different elements

hydrophbic

Water fearing

Hydrophilic

Attracted to water, or water loving

Amphipathic molecule

Molecule with a polar and nonpolar regions

Monosaccharides (reg def)

The simplest carbohydrate, active alone or serving as a monomer for disaccharides and polysaccharides. Also known as simple sugars, the molecular formulas of are generally some multiple of CH2O. (REDUCING SUGARS) EX: GLUCOSE

Funtion: Energy storage {General def}

Monosaccharides (Text book def)

many kinds ranging from 3-10 carbons. All monosaccharides have carbonyl groups (COH) either a free terminal ALDEHYDE GROUP or a free initial KETONE GROUP

disaccharides

A sugar formed when two monosaccharides are joined by glycosidic linkage. Example: sucrose

Function: energy storage.

formed through dehydration synthesis.

glycosidic bond

A glycosidic bond is a covalent bond in which a carbohydrate binds to another group, which could also be a carbohydrate. A glycosidic bond is found between the two glucose molecules in maltose. (red in pic is a glycosidic bond)

Oligosaccharides

short chains of 3 or more monosaccharides (at least 10). when bonds are short)

Polysaccharides

large macromolecules formed from monosaccharides. (when bonds are long). EXAMPLES: starch, glycogen

FUNTION: energy storage and structural components

formed though dehydration synthesis

-subunits (monosaccharides), joined through glycosidic bonds

starch

A storage polysaccharide in plants consisting entirely of glucose.(associated with lugols test)

glycogen

storage form of glucose in animals. (associated with lugols test)

Cellulose

main carbohydrate component used in plant cell walls.

peptidoglycan

A protein-carbohydrate compound that makes the cell walls of bacteria rigid

Chitin

A structural polysaccharide, consisting of amino sugar monomers, found in many fungal cell walls and in the exoskeletons of all arthropods.

what are organic molecules?

molecules that contain carbon-carbon or carbon -hydrogen bonds (often also contain nitrogen, phosphorous, oxygen, and sulfur)

most organic molecules found in living organisms belong to what four groups?

carbohydrates, lipids, proteins, nucleic acids

carbohydrates

consist of carbon, hydrogen, and oxygen 1:2:1 ratio (approximately)

what are 3-carbon, 5-carbon, and 6-carbons called

3: triose

5: pentose

6: hexose

carbonyl group consist of two groups what are they?

free terminal ALDEHGYDE group or a free internal KETONE group.

what makes monosaccharides reactive?

a double bonded oxygen in the free aldehyde or ketone group make monosaccharides reactive

Reducing sugars are detectable using what test?

Benedicts test

Benedicts test

reducing sugar R-COH and oxidized benedicts reagent CU+2

- only molecules that have ketones and aldehydes.

oxidizing reducing sugar R-COOH + reduced benedict's reagent cu+

dehydration synthesis

A chemical reaction in which two molecules are bonded together with the removal of a water molecule.

common disaccharides and what they consist of?

sucrose: glucose and fructose

lactose: glucose and galactose

maltose: glucose and glucose

are disaccharides also reducing sugars?

only if the disaccharide has a free aldehyde or free ketone group.

which of the following disaccharides will give a positive reaction in the benedicts test? sucrose or maltose?

maltose since there's a free aldehyde group( is a reducing sugar). while sucrose lacks a free aldehyde or ketone group (not a reducing sugar).

how can you detect the presence of starch and glycogen?

lugols test

lugols test

starch and glycogen formed coiled structures called alpha helixes. Iodine in the lugols test reagent (I2 KI) binds within the alpha helix. Reagent is a yellow orange.

alpha helix

the spiral shape resulting from the coiling of a polypeptide in a protein's secondary structure

starch in lugols test. Is it more intense than glycogen or less intense?

starch produces a more intense reactions because the polymers are long with few branches, binds more iodine

glycogen in lugols test

produces a less intense reaction because the polymers are shorter with more branching, binds less iodine.

What are lipids?

a heterogeneous group comprised of molecules such as:

-charactered by many carbon-carbon and carbon-hydrogen

bonds

\***NON POLAR/ HYDROPHOBIC

-fats/oils:

-phospholipids

-steroids

what are the functions of lipids?

-energy storage

membrane structure

-fat soluble hormones

MAIN IDEA: non-polar / hydrophobic

Triglycerides

an energy-rich compound made up of a single molecule of glycerol and three molecules of fatty acid. are a type of liquid

fats and oils are commonly what?

triglycerides with very small chemical composition

fats are composed of what?

SATURATED fatty acids

example hard fat: fatty acids with single bonds between all carbon pairs.

oils are composed of what?

UNSATURATED fatty acids

example oil: fatty acids that contain double bonds between one or more pairs of carbon atoms

Sudan IV Test

the Sudan IV tests detects the nonpolar properties of lipids

DETECTS LIPIDS (for short).

- Sudan IV is a nonpolar dye that is soluble in non polar substances ( like lipids) but not in polar substances ( like water).

- Sudan iv is soluble to lipids like oil

what are proteins?

subunits called amino acids join through covalent bonds called peptide bonds to form polypeptides

- subunits joined using dehydration synthesis

what are some functions of proteins?

-enzymes

-various cell structures

-antibodies

-transport molecules

- transcription factors

amino acids

The 20 molecules that are held together by peptide bonds to make up proteins.

examples: glycine and arginine

structure of amino acids

central carbon with four bonds, hydrogen, amine group (NH2), carboxyl group (COOH), side chain or R group.

Ninhydrin Test

detects amino acids

- the ninhydrin test reagent is yellow and reacts with free amine groups found in amino acids

which means the amine group is not bound to another molecule.

\***all amino acids except proline, react with ninhydrin to produce a purple color.

What amino acids doesn't react while conducting the ninhydrin test?

All amino acids except proline, react with ninhydrin to produce a purple color.

what is different about proline?

the amine group of proline is part of a ring structure so it is not as free to react with ninhydrin

Biuret test

polypeptides formed by dehydration synthesis to join amino acids through peptide bonds

1 amino acid + 1 amino acid \= 1 protein

DETECTS PEPTIDE BONDS

-blue cu2+ in the reagent is reduced to purple cu+

positive control

a reaction is expected- COLOR CHANGE

negative control

no reaction is expected no color change

pos and neg control for benedict's test

POSITIVE: (+) MALTOSE,GLUCOSE

NEGATIVE: (-) WATER,SUCROSE,GLYCOGEN,STARCH

(only red is positive)

pos and neg for lugols test

POSITIVE: (+)STARCH, GLYCOGEN

NEGATIVE:(-) WATER,GLUCOSE,MALTOSE,SUCROSE

pos and neg controls for biurets test

POSITIVE: (+) ALBUMIN