Biological molecules topic 2

BIO SL

what is a covalent bond?

a bond that forms when 2 atoms share a pair of electrons

how are electrons shared in nonpolar covalent bonds?

share electrons equally

how are electrons shared in polar covalent bonds?

share electrons unequally

How many covalent bonds can a carbon atom form?

4 covalent bonds

What does the term "unsaturated" mean in relation to carbon compounds?

Unsaturated carbon compounds contain double or triple bonds between carbon atoms

Define the term functional group.

A functional group is a specific group of atoms within a molecule that gives organic compounds their individual properties.

what makes an “organic” molecule

carbon-based with hydrogen presence

what’s the anatomy of a carbon atom?

6 protons 6 neutrons 4 valence electrons

what’s another word for outer shell

valence

what is a covalent single bond?

when carbon shares ONE pair of valence electrons w/ another atom

what is a covalent double bond?

when carbon shares TWO pairs of valence electrons w/ another atom 

what are the 4 major classes of carbon compounds used by living organsms

carbohydrates, proteins, lipids, nucleic acids

define a chemical bond

an attraction between atoms, ions, or molecules when atoms transfer or share electrons between atoms

what is an ionic bond?

when atoms transfer electrons. its the electrostatic attraction between oppositely charged ions in a chemical compound.

what are the 3 function groups?

hydroxyl, carboxyl, phosphate

define function group

an atom or group of atoms within a molecule that has similar chemical properties

How do hydroxyl (-OH) form hydrogen bonds?

polar covalent bonds between O & H allows hydroxyl to form hydrogen bonds

molecules with which function group will be hydrophilic/ soluble in water?

hydroxyl (-OH)

what is an example of hydroxyl (-OH)?

beta glucose

what are the properties of carboxyl (-COOOH) 

• carboxyl group is acidic

• it can lose it’s hydrogen ion (H+) to form a stable anion (-COO^-)

• -OH of carboxyl is polar = form hydrogen bonds w/ other molecules

what’s an example of carboxyl (-COOOH)

Fatty acid, amino acid alanine

what is Phosphate (-PO4^-)  group made of? what does it form

• 4 oxygen atoms

• forms a negatively charged, highly polar & hydrophilic functional group that can form hydrogen bonds

• can also make ionic bonds

whats an example of Phosphate (-PO4^-) 

ATP (adenosine triphosphate)

define a monomer

basic building block molecules that are capable of being linked together to form larger structures

how to break covalent bonds

hydrolysis, no enzymes (?)

how do monomers make biological polymers

they combine through condensation reactions

define polymers

large complex molecules made of repeating monomers aka. a chain of monomers = polymer

what are examples of biological monomers → biological polymers

nucleotides → nucleic acids (DNA RNA)
monosaccharides → polysaccharides
amino acids → proteins

what are condensation reactions

what builds polymers from monomers

what are the properties of condensation reactions 

• its an anabolic process that requires energy (ATP) 

• builds large molecule from smaller molecules through a metabolic pathway

• forms water as a byproduct

what is a metabolic pathway

series of chemical reactions that happen inside a cell where each chemical reaction is controlled by a specific enzyme

whats an example of condensation reaction?

monomer_1(hydroxyl -OH) + monomer_2(hydrogen -H)
→ water_byproduct 
→ new covalent bond, polymer

what’s an example of polymerization (a type of condensation reaction)

what happens in condensation reaction for carbohydrates?

• 2 monosaccharides link together to make disaccharides

• multiple monosaccharides link together to make polysaccharides (aka carbohydrates)

what are the examples of condensation reaction for carbohydrates (monosaccharide → disaccharide → polysaccharides)

glucose → maltose (glucose + glucose) → starch

fructose → sucrose (glucose + fructose) → glycogen
galactose → lactose (glucose + galactose) → cellulose

what is an example of condensation reaction for lipids

glycerol undergoes condensation reactions with 3 fatty acids molecules to form triglycerides

what is an example of condensation reaction for proteins

amino acids undergo condensation to form dipeptides then tripeptides and eventually long polypeptide chains that fold into functional proteins

what is an example of condensation reaction for nucleic acids

nucleotides connect via condensation reaction between the phosphate group of one nucleotide and the pentose sugar of the next to create the sugar-phosphate backbone of DNA and RNA molecules

define Hydrolysis reaction

breaks apart complex molecules, making monomers by digesting polymers


→ reverse hydrogen reaction

what are the properties of hydrolysis reactions

• catabolic process: metabolic process that breaks down complex complex molecules into simple molecules releasing energy in the process

• water is added back yay

what is an example of hydrolysis reaction for carbohydrates

polysaccharides such as starch, glycogen, cellulose break apart to form monosaccharide monomers

what is an example of hydrolysis reaction for lipids

triglycerides undergoes hydrolysis to form glycerol and 3 fatty acid molecules

what is an example of hydrolysis reaction for proteins

polypeptide chains that form functional proteins hydrolysis to make amino acid monomers

nucleic acids

the sugar-phosphate backbone of DNA RNA molecules can go through hydrolysis to break part individual nucleotides

define monosaccharide

simplest carbohydrates, made of single sugar molecules that cannot be hydrolyzed

whats the general formula for monosaccharide?

(CH2O) w/ different amount of carbon atoms

what are pentoses (include example)

five carbon monosaccharides
ribose & deoxyribose

what are hexoses (include example)

six carbon monosaccharides
glucose & fructose

C6H2OH - which glucose is this?

alpha glucose

CH2OH - which glucose is this?

beta glucose

define isomer

exactly same formula (atoms) with different recipe (different atom arrangement) e.g alpha beta glucose

what is the strongest bond that holds atoms together within biological molecules?

covalent bonds

what makes a molecule soluable

hydroxyl (-OH)