Bio 120- Energy and Enzymes

What is bio energy

The energy required for living cells

Anything that can be transformed into heat

What is chemical energy?

The energy stored in all chemical molecules

What is dependant on the energy stored in chemical?

The potential energy is different according to the arrangement of there atoms

How can potential energy be maximized in a molecule?

BY breaking down energy rich food (sugars and fats) to simpler compounds such as CO2 and H2O

What is cellular metabolism?

the sum of chemical activities within a cell

What are the two metabolic pathways? Explain

1. Anabolism:

   Complexe molecules being synthesized from simple compounds

2. Catabolism (cataclysm):

   Large molecules being broken down to smaller ones

What’s a metabolic pathway?

The sequence of enzyme-catalyzed reactions

Which way does the energy go in anabolitic Rx?

It is brought into THE rx to create energy rich molecules

Which way does the energy go in catabolitic Rx?

It is produced from the rx- energy output

What needs to be constant for the energy in a system to be able to perform work?

Temperature and Pressure

What is free energy?

It’s delta G

The maximum amount of free energy available to do work

Reactant(A)———- Product (B) + delta G

Describe a spontaneous rx

A reaction that happens on its own without outside energy input

Describe an exergonic Reaction

When energy is released as the result of the reaction. The products have less PE than reactants

Describe an endergonic reaction?

When a reaction requires energy to react. The products have more PE than the reactants

Ex: glucose synthesis (photosynthesis)

Energy coupling reaction?

Using energy produced from an exergonic reaction to do an endergonic reaction

What do reactions need to regulate their Reactions?

Enzymes

What is the energy of activation?

An amount of energy needed before a reaction can occur. Also thought as an energy barrier

What is the main role of (protein) enzymes?

To lower the energy of activation of specific rxs

What is an enzyme?

• A protein complex/ single polypeptide that serves as a catalyst. It is not a part of the reaction

What are some secondary roles of enzymes?

• Allows equilibrium to be attained faster

What is the difference between an enzyme and a substrate?

How can enzyme activity be regulated?

• inhibitors, pH, temperature

What are some different non-protein complexe enzymes require?

• Cofactor

• Coenzymes

• Prosthetic group

What’s a cofactor?

Inorganic ions:

• copper

• iron

• zinc

  all binds to certain enzymes

What’s a coenzyme?

Organic carbon molecules.

Energy carriers

Not permanently attached

• CoA,

• NAD
  FAD

• ATP

What’s a Prosthetic group?

Distinct molecules that are permanently bound to enzyme

EX: hemoglobin to blood that carries the O2 in blood

What’s the main bioenergy carrier in living cells ?

ATP or adenosine 5’-triphosphate

Describe the ATP dynamic within a cell

• For immediate use, the energy is stored in ATP

• Very active

• The energy is stored in form of chemical bonds

What’s the structure of ATP

Adenine-nitrogen organic base

Ribose- 5 carbon sugar

Three phosphate groups (oxygen around phosphorus

How does ATP release energy? What type of reaction is it?

• Hydrolysis- exergonic Rx (addition of water to separate a phosphate group)

• Releases -7.6Cal/ mol

• When the phosphate group does not bind to another molecule

ATP + H20————-ADP + Pi + delta G(-7.4kcal/ mol)

Most cellular works depend on which reaction reaction?

Phosphorylation: when ATP energizes other molecules by transferring a phosphate group

Describe the formation of sucrose?

Through what type of reaction does the formation of glucose occur?

A coupling reaction (redox rx)

Describe how ATP drives cellular work

Moto proteins move via cytoskeletal actin filaments to do mechanisms activated by the hydrolysis of ATP

What are examples of coupling reaction that ATP hydrolysis powers?

• sucrose formation

• protein phosphorylation (change structures that aids in signaling transduction)

  yin-yang

Explain a coupling reaction

ATP works through a phosphorylation (addition of a phosphate group to a molecule)

What is the most ancient passing of cells in the making of ATP?

The formation of glucose as a substrate-level phosphorylation

What are the two ways to generate ATP?

• Substrate-level phosphorylation

• Chemiosmosis

Describe how substrate-level phosphorylation works

When a phosphate group is transferred to ADP from an intermediate compound called substrate

Describe how chemiosmosis works

When the phosphorylation of ADP to ATP is linked to the transfer of an electron through and electron transport chain.

What are the two types of chemiosmosis?

• Oxidative Phosphorylation

• Photophosphorylation

Describe how oxidative phosphorylation works

When ATP synthesis comes from the transfer of electron to oxygen (last part of cell respiration)

Describe how photophosphorylation works

ATP synthesis driven by light (sunlight such as photosynthesis)

How do cells transfer energy?

Through REDOX reactions

• Substance oxidized looses energy (electrons)

• Substrate reduced gains energy (gains said electron)

Which are the most common acceptor molecules in a living cell?

NAD+ to NADH :

NADP+ to NADPH

FAD+ to FADH2

Cytochromes (Feiii) to Cytochromes (Feii)

Quinone (Q) to Quinone (QH2)

What are the bioenergy carrier important for (process)?

Photosynthesis and cellula