Chapter 2: Cell Chemistry and Bioenergetics

intense workout

It occurs in the muscles of humans during a(n) ________.

W

________= work done; P= pressure; ΔV= change in volume.

Q

________: energy given to the system; w: work done on the system; ΔE: change in internal energy.

large molecules

It confers stability to form ________.

Eg

Hydrochloric acid (HCL)

Fungi

Oil and glycogen

Humans

Glycogen

Plants

Starch

Organic Chemistry

It is the study of hydrocarbons and their derivatives.

Covalent bond

A chemical bond that involves the sharing of electrons to form electron pairs between atoms.

Non-covalent bond

The bond in which no sharing of electron pairs takes place is called a non-covalent bond.

Hydrogen bond

A hydrogen bond is the interaction of a hydrogen atom with an electronegative atom, such as nitrogen, oxygen, or fluorine from another molecule.

Acids

Substances that release protons when they dissolve in water thus forming H3o+ are termed acids.

Bases

The opposite of acid is a base. Substances that accept a proton from a water molecule are called bases.

ph scale

The concentration of H3O+ is expressed using a logarithmic scale called as pH scale.

Strong acids

Those who lose their protons quickly. Eg: Hydrochloric acid (HCL).

Weak acids

Those who hold on to their proton more tightly when dissolved in water. Eg: Acetic Acid (C2H5COOH)

Strong base

Those who readily dissociate in water to form respective ions. Eg: Sodium Hydroxide (NaOH)

Weak base

Those who have a weak tendency to reversibly accept a proton from water. Eg: Ammonia (NH3)

Buffers

It is a solution that can resist pH change upon the addition of an acidic or basic component.

Macromolecule

It is composed of a much larger number of atoms than ordinary molecules.

Micromolecule

It is a small molecule that often joins together to form a larger type of molecule. It is often referred to as monomers.

Metabolism

It is the set of chemical reactions that occur to maintain life.

Catabolic reactions

These reactions break down molecules into smaller units.

Anabolic reactions

These reactions use the small molecules and the energy harnessed by catabolism to drive the synthesis of molecules.

Thermodynamics

branch of science which deals with the energy changes taking place in all physical and chemical processes

Work

The product of force and displacement is called work

System

It is any region of space that is under thermodynamic investigation.

Surrounding

It comprises the rest of the universe apart from the system.

Open system

This type of system can exchange energy as well as matter with the surrounding.

Closed system

This type of system can exchange energy, but not matter with the surroundings.

Universe

It comprises the system and its surroundings together

Boundary

A wall or layer separating the surrounding.

Internal energy (E)

It is defined as the sum of different energies associated with its atoms and molecules.

Enthalpy (H)

Heat contained in the system measured at constant pressure.

Spontaneity

It defines whether a chemical reaction will occur or not.

The second law of thermodynamics

States that in the universe or any isolated system the degree of disorder always increases.

The first law of thermodynamics

* This law is based on the law of conservation of energy.
* Energy can neither be created nor be destroyed but can be transformed from one form to another.

Spontaneous Reaction

Reaction which can occur by itself without any external force.

Non-Spontaneous Reaction

Reaction which cannot occur by itself.

Entropy

It is a measure of randomness or disorder in a system. The greater the disorder, the greater the entropy.

Gibb’s Energy (G)

It is the part of the total energy of the system which can be converted to useful work.

Relationship between standard Gibb’s energy change (∆G°) and Equilibrium Constant (Keq)

∆G° = - RT ln Keq

Oxidation

It is the loss of electrons or an increase in the oxidation state of a chemical or atoms within it.

Reduction

It is the gain of electrons or a decrease in the oxidation state of a chemical or atoms within it.

Hydrogenation

It is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst.

Dehydrogenation

It is the process by which hydrogen is removed from an organic compound to form a new compound.

Activation Energy

It is the minimum amount of energy that must be provided for compounds to result in a chemical reaction.

Enzymes

A substance produced by a living organism that acts as a catalyst to bring about a specific biochemical reaction.

Coenzymes

Coenzymes are small molecules. They cannot by themselves catalyze a reaction but they can help enzymes to do so.

Substrates

Each enzyme binds tightly to one or more molecules called substrates.

Catalysts

A substance that can lower/increase the activation energy of a reaction.

ATP

Adenosine Tri Phosphate

ADP

Adenosine Di Phosphate

NADH

Nicotinamide Adenine Dinucleotide

NADPH

Nicotinamide Adenine Dinucleotide Phosphate

FADH2

Flavin Adenine Dinucleotide

PPi

Pyrophosphate

Glycolysis

The major process of oxidizing sugars is the sequence of reactions known as glycolysis.

Alcoholic Fermentation

The process is hazardous either acid or alcohol is produced. Yeats poison themselves to death when the concentration reaches about 13%.

Lactic acid fermentation

It occurs in the muscles of humans during an intense workout.

Oxidative Phosphorylation

The process that connects glycolysis and Krebs’s Cycle.

Krebs’s Cycle

It occurs in the mitochondria matrix of the eukaryotic cell but in prokaryotes, it occurs in the cytoplasm.

Fungi

Oil and glycogen

Humans

glycogen

Plants

starch