• Energy

• ATP: Energy for Cells

• Metabolic Pathways & Enzymes

• Oxidation-Reduction

Metabolism – the Dynamic CellSpring 2013 - Althoff Reference: Mader & Windelspecht Ch. 6)

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What is Energy?

• ___________ energy• Constantly converted to

kinetic energy

• Energy of ____________• Constantly converted to

potential energy

Potential Energy Kinetic Energy

= the __________________, quantified by…_______ = amount of heat required to raise the

temperature of 1g of water 10C

Successful organisms “_____” the energy game

• FIRST LAW OF THERMODYNAMICS (LAW OF CONSERVATION OF ENERGY) Energy cannot be created or destroyed, but it can be changed from one form to another

• SECOND LAW OF THERMODYANMICS Energy cannot be changed from one form to another without a loss of usable energy. Also associated with the term __________

--the relative amount of disorganization associated with every energy transformation

__________ LAWS

MORE organized LESS organized

GLUCOSECARBON DIOXIDE

& WATER

• Less ___________• More potential energy• More organized

• More ____________• Less potential energy• Less organized

LESS Entropy MORE Entropy

• 1 adenosine group

• 3 phosphate groups (triphosphate)

_____: what cells spend for energy

Flow ofEnergy

CHLOROPLAST

MITOCHONDRION

CHEMICAL WORKTRANSPORT WORKMECHANICAL WORK

• ______________ WORK —ex: protein, lipid, carbohydrate synthesis or breakdown of those complex organic molecules

• ______________ WORK —ex: move molecules from one location to another, especially across the plasma membrane

• ______________ WORK —ex: muscle contractions, cilia and flagella to beat, chromosomes to be moved

Functions of ATP…

• _____________ REACTIONS —ENERGY REQUIRED, RESULTS IN _______________ OF COMPOUNDS

• _____________ REACTIONS —ENERGY REQUIRED, RESULTS IN _______________ OF COMPOUNDS (chemical bonds are broken)

Metabolic Reactions

__________________ = all of the chemical reactions that occur in a cell during growth and

repair

• Enzymes ____________ these reactions• Enzymes only speed up reactions, they

______________ make reactions that are not possible to begin with

• Enzymes can “bring together” molecules that will react to each other AND reduce the ___________________

• Enzymes can be “_____________”

METABOLIC __________ = series of linked reactions that begin with a particular reactant (i.e. SUBSTRATE) and terminate with an end product

____________ = protein molecule that functions as a catalyst in a chemical reaction (i.e, metabolic pathways)

METABOLIC PATHWAYS & ENZYMES

• A metabolic pathway can be represented by a simple diagram.

– The letters A-G indicate ________________– The letters E1-E6 represent _______________.– A is the substrate for E1, B is the substrate for E2,

and so on.

E1 E2 E3 E4 E5 E6

A B C D E F G

REACTANT

Po

ten

tia

l en

erg

y

Reaction

PRODUCT

Less energy needed for activiation WITH ENZYME

More energy needed for activiation

________________ENZYME

Ra

te o

f R

ea

ctio

n(p

rod

uc

t p

er u

nit

of

tim

e

Temperature 0C

What affectsenzymes?

Rate

of R

eacti

on(p

rodu

ct p

er u

nit o

f tim

e)

pH

What effectsenzymes? pH

“____________”

in stomach

pH

“_______________”

in small

intestine

Enzyme Reaction occurs Enzyme

Substrate(reactants)

Products

Reactants “_________________” on the enzymeReaction occurs ____________ because of enzyme Product results and enzyme is ‘______________’

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Say it with “…______”: NAMING OF ENZYMES

• Lipid Lipase• Urea Urease• Maltose Maltoase• Lactose Lactase• Sucrose Sucrase• Ribonucleic acid Ribonuclease• some proteins Trypsin• some proteins Pepsin• Etc.

Substrate/Reactant Enzyme

Oxidation & Reduction• OXIDATION – _______ of electron(s) by

molecules during the oxidation-reduction process

• REDUCTION –_______ of electron(s) by molecules during oxidation-reduction process

• Both processes all take place at the same time

• Take place during photosynthesis and cellular respiration

For the record…• PHOTOSYNTHESIS is the _________ of CELLULAR

RESPIRATION

6CO2 + 6H20 + ENERGY C6H1206 +6O2

C6H1206 +6O2 6CO2 + 6H20 + ENERGY

PHOTOSYNTHESIS: H2O is oxidized, CO2 is reduced

CELLULAR RESPIRATION: C6H12O6 is oxidized, O2 is reduced

________________ – moving H+

• The production of ATP due to a hydrogen ion (H+) ___________ across a membrane

• Occurs in _________________ and _________________…the energy organelles of cells

Starts with H+ pump pumping H+ _______ the membrane

Completes when H + ions cross back through the membrane through an ________________ complex

Mader, p115 – summary, Fig. 6.13

Chemiosmosis – moving H+

Low H+ conc.

High H+ conc.

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