Biochemistry

What are all living things composed of?

Matter

What is matter

Anything with mass and volume

What is everything made of in simplest form

Elements

Describe the bohr rutherford model

Atoms are mainly empty space

Nucleus contains protons and neutrons

Electrons orbit the nucleus in defined shells

What is an isotope

Elements with different numbers of neutrons

what do nuclei of radioisotopes release whilst decomposing

Sub atomic particles and radiation

What can isotopes be used for medically? Give an example

Used as bio tracers in bio research and medicine. Eg. Iso iodine injected in bloodstream to check thyroid

How is molecular polarity determined

By electronegativity

What determines molecular shape?

Bonding electrons (valence electrons)

What do intermolecular forces determine?

Physical state of matter

What are the types of intermolecular forces?

• London dispersion

Dipole dipole - H- bonding

Ion- dipole

What are important properties essential for life in water (6)

• ability to form h- bonds

• High heat cap

• High heat of vaporization

• Universal solvent

• High surface tension

• Less dense in solid state.

What do acids increase

concentration of H+ (hydronium)

What do bases increase

Concentration of OH- (hydroxide)

What do neutral substances contain

Equal concentrations of hydroxide and hydronium

What is the pH equation

pH=-log[H+]

How do you know if an acid/base is strong

They ionize completely in water

How do you know if an acid/base is weak?

They partially ionize and form an equilibrium in water

What do buffers do?

They protect organisms against fluctuations in pH

What does a buffer system contain?

A weak acid and its conjugate base in equilibrium

What is a conjugate base?

The species that remains after an acid donates a proton

What is a conjugate acid?

When a base accepts a proton

Give an example of a buffer system and where it is usually found

Carbonic acid-bicarbonate buffer. Common in living things

Describe the process of the carbonic acid- bicarbonate buffer system

• carbon dioxide (CO2) and water (H2O) react to produce carbonic acid (H2CO3)

• ionizes to bicarbonate (HCO3)

• Increase in blood acidity produces more carbonic acid

• Decreased blood acidity causes carbonic acid to again ionize maintaining the equilibrium

What is the equilibrium equation of the carbonic acid-bicarbonate buffer

H2O+CO2 ←> H2CO3 ←> HCO3 + H+

What is the bulk of all organisms

Water

What is the the remaining dry weight of organisms composed of

Carbon containing molecules (organic molecules)

What are compounds produced by living things called

Biochemicals

What element does biochemistry center around

Carbon

How many valence electrons does C have?

4

What is a hydrocarbon composed of?

Hydrogen and Carbon

Break down the word hydrogen

Hydro → water

Gen → genesis → the beginning

What is the simplest organic molecule group

Hydrocarbon

What is a saturated hydrocarbon

Hydrocarbon with single bonded carbon atoms

What is an unsaturated hydrocarbon

A hydrocarbon with double or triple bonded carbon atoms

What is an isomer

Two molecules having the same formula but different structure or bond orientation

What are macromolecules responsible for

Properties of life

What do macromolecules do?

Form structures and carry out complex and precise activities in cell

How many carbon atoms do macromolecules contain?

Anywhere from dozens to millions of C atoms

What do carbohydrates include?

• simple sugars

• Oligosaccharides

• Polysaccharides

What are simple sugars?

Mono- and disaccharides

What is a monosaccharide?

Sugars that are made up of only one molecule

What are the two groups of monosaccharides

• aldose → has an aldehyde functional group

• Ketose → has a ketone func. Group

Aldose examples

Glucose

Galactose

Ketose example

Fructose

What is a disaccharide?

Sugars made up of two molecules?

How do sugars pin together?

With glycosidic bonds

What is a glycosidic bond?

A type if covalent bond that links a carbohydrate to another group. Can be classified as alpha or beta depending on bond orientation relative to sugar ring.

What classifies a glycosidic bond as an alpha bond?

It is below the plane of the sugar ring

Example of an alpha bonded disaccharide?

Maltose

What characterizes a glycosidic bond as a beta bond?

It is above the plane of the ring

Example of a beta bonded polysaccharide

Cellulose

What is the purpose of a disaccharide?

They are ready stores of energy

Examples of disaccharides (3)? What are they made from

• sucrose (glucose , fructose)

• Lactose (glucose+ galactose)

• Maltose (glucose +glucose)

What is an oligosaccharide? What is ine function?

• small chains made of 3-10 simple sugar units linked together

• Act as markers on cell membranes

What is a polysaccharide? Examples?

Long chains of simple sugars. Eg. Starch (unbranched) , glycogen (branched), cellulose.

Polysaccharide use?

Can be used for energy storage ( glycogen and starch) or structural components (cellulose)

What is the use of carbohydrates?

Stores of chemical energy and cellular building materials

Carbohydrate general formula

(CH2O)N

What does the suffix -ose refer to?

Sugars

What is a dehydration reaction?

Removal of -OH and H from two reactant molecules to form a larger molecule and water

Hydrolysis reaction

Bond in a larger molecule is broken and H2O is added

Oxidation reaction

Loss of electrons

Reduction reaction

Gain of electrons

What is this reaction called (Oxidation → reduction)

Redox reaction

What is a buffer

A weak acid/ base that can conpensate changes in a solution to maintain a proper pH balance

What is a lipid

A diverse group of non-polar molecules

What do lipids include (5)

• fatty acids

• Fats

• Waxes

• Steroids

• Phospholipids

What is a fatty acid

Long unbranched hydrocarbon chains with a single carbonyl group (double bond oxygen)

What is a fat

Glycerol linked three fatty acids by ester bonds (triglycerides)

What are amphipathic fats

Fats with a a hydrophilic and hydrophobic component

What is a wax

Long fatty acids linked to alcohols or rings . They are hydrophobic nonpolar and soft solids

What are steroids

Steroids are built around a four ring hydrocarbon skeleton

Example of a steroid

Cholesterol

What does cholesterol do?

Maintains cell membrane fluidity and is the precursor for many hormones

What are phospholipids

Lipids with a non polar tail and polar head. They are main components of cell membranes

What are proteins?

Polymers of amino acid subunits held together by a peptide bond

What is protein structure coded by

DNA

What is dna

Deoxyribonucleic acid

What is denaturation

The altering of a protein chemically that cannot be reversed

How many structures of proteins are there?

4 structures

What is the primary structure of proteins

Sequences of amino acids

Secondary structures of proteins

Alpha helixes (hair)

Beta pleated sheets (silk)

Tertiary structure of proteins

Alpha helixes or beta pleated sheets folding onto itselves

Quaternary structure of proteins

2 or more subunits assemble

Two types of nitrogenous bases

• purines

• Pyrimidines

What distinguishes purines and pyrimidines

Purines have a double ring structure

Pyrimidines have a single ring structure

Purine nitrogenous bases

• guanine

• Adenine

Pyrimidines

Cytosine

Thymine

What are two nucleic acids name

Dna and RNA

What three things do nucleotide subunits consist of

• nitrogenous base

• Pentose sugar

• Phosphate group

What does RNA contain instead of thymine?

Uracil

What also has a nucleic acid component?

ATP - adenosine triphosphate

What is the DNA AND RNA structure?

• phosphate groups form backbone of strand

• Purines bind with pyrimidines in the “staircase”

• Dna forms double helix

• Rna forms single strand of complex folded shapes

What pyrimidine does the purine adenine bind with?

Thymine

What pyrimidine does the purine guanine bind with?

Cytosine

in rna what does the purine adenine bind with?

Uracil

How were enzymes discovered

Buchner in the late 19th century added sugar to yeast extract to preserve it. The activity that he observed were due to unique catalaysts called enzymes

What does the greek term for enzymes mean

In yeast

What are enzymes?

Protein catalysts