AP BIO UNIT 3 - Enzymes

What are some physical indicators of a reaction? (4)

1) Fizzing

2) Gas

3) Color Change

4) Temperature

Exothermic Reaction

When heat energy is released

Endothermic

When heat energy is absorbed

Exergonic Reaction (Spontaneous)

Occurs when reactions come close to each other;

Endergonic Reaction (Not Spontaneous)

Reactions that require a sort of activation energy to occur.

When an exergonic reaction releases heat energy….

That energy can be used to power an endergonic reaction

Name the two ways to start a reaction

1) Activation energy

2 Enzymes

Enzymes

biological organic catalysts

ALWAYS PROTEINS

Allow for chemical reactions to occur by lowering the Activation Energy

What are some environmental factors that decrease enzyme activity?

1) temp

2) PH

Active Site

the part of the enzyme where the reaction occurs

Hydrolytic Enzymes

enzymes that break things down

Induced Fit Model

enzymes can slightly change/adjust to its active site so that it can fit the substrate (the enzyme flexes)

Macromolecule →(hydrolysis) building block

←(synthesis)

The types of enzymes.

What happens to an enzyme if you increase and decrease the temperature?

the rate of the reaction occurs faster, then the enzyme will denature. If temp decreases, the rate of the reaction becomes slower, so there will be no collisions at all.

Coenzyme

an organic compound that binds to the active site of the enzyme and assists the enzyme. 

Cofactors

Coenzymes that are inorganic

Allosteric site

the product of the enzyme that attaches to a different part of the enzyme to temporarily shut it off, until it starts again to repeat the process..

Feedback Inhibition

The product binds to the allosteric site and deactivates the enzyme

Inhibitors (name the types and definition)

inhibit chemical reactions

1) competitive inhibitor

2) non-competitive inhibitor

competitive inhibitor

competes with the substrate for the active site

noncompetitive inhibitor

particle binds to the allosteric site.

Aerobic Respiration (what is the formula, where does it occur, and what kind of reaction is it?)

Occurs in the mitochondria

C6H12O6 + O2 →(enzymes) CO2 + H2O + 38/36 ATP

This is an exergonic,exothermic, spontaneous reaction. It releases heat energy

You can only transfer 33% of chemical energy (not efficient)

What cells go through Aerobic respiration?

ALL EUKARYOTIC CELLS,

some prokaryotic cells go through this across their cell membrane

Anaerobic Respiration (what is the formula, where does it occur, and what kind of reaction is it?)

Occurs in the cytosol

C6H12O6 →alcohol/ethanol + CO2 + 2ATP

Another word for anaerobic Respiration?

Fermentation

2 Types of Anaerobic Respiration

Fermentation (yeast does this)

Lactid Acid Fermentation (animals do this) : C6H12O6 →lactid acid + 2ATP

Oxidation

hydrolysis: losing electrons and breaking bonds increasing the charge and making smaller molecules

Reduction

Synthesis: gaining electrons and forming bonds (reducing the charge and making a bigger molecule)

High energy oxidizes to…

Low energy

ATP →

ADP+ inorganic molecule

NADH →

NAD+

FADH2→

FAD

NADPH

NADP+

In order for cellular respiration to occur, what HAS to occur?

Glycolysis

When you add a phosphate to a molecule its called

Phosphorylation: makes the molecule more energetic and unstable so that it can split

Enzymes are the cause of

Phosphorylation

What class of enzymes Phosphorylate, and what does it break into?

kinases

It breakes molecules into 2 , 3 carbon sugars(PGAL)

PGAL

Phosphoglyceraldehyde

Intermediates

the middle reactions in the oxidation process.

Glycolysis Reaction

-

Where does glycolysis occur?

cytoplasm

The Mitochondria

Has 2 membranes

1) The outer membrane

2) intermembrane space

Self replicating

Name the compartments(spaces) of the mitocondria

The intermembrane space

the matric

How do Prokaryotic cells resemble the mitocondria?

they have free ribosomes

When you hear double membrane, think of

endocytosis

The Endosymbiotic Theory

There is a symbiotic relationship b/w the cell and the mitochondria

(They CANNOT live w/o each other)

Membrane Bound Organelle Diagram

-

Apoptosis

The suicide program

If there is something wrong with the cell, the cell will die. 

In order for cellular respiration to occur…

glycolysis has to occur.

Glycolysis breakdown

Glucose →(Oxidizes 2 ATP into ADP) → 2 PGAL

2 PGAL → (2NAD+ and 4ADP gets REDUCED to 2NADH and 4ATP (2 ATP net gain) → Pyruvate

Kreb Cycle break down

Acetyl CoA and oxaloacetate react to produce citric acid, then breaks it down into smaller organic compounds.

WHEN CITRIC ACID IS BREAKING DOWN, 2 ATP is produced, 6 NAD+ and 2 FAD+ is being reduced to 6NADH and FADH2 , and 4CO2 is being released.

Pyruvate →Acetyl CoA breakdown

Pyruvate is broken down into Acetyl CoA (a coenzyme)

Pyruvate →( 2 NAD+ gets reduced to NADH, & 2 CO2 is being released) → acetyl CoA is produced.

what is the functional group of pyruvate?

Acetyl group! (put the picture)

Where does the Kreb Cycle Occur

Matrix of the Mitochondria

Where does glycolysis occur?

the cytoplasm

Where does the pyruvate to Acetyl CoA occur?

matrix of the mitochondria?

Intermediate steps of Aerobic Respiration to making ATP

Glycolysis (2 ATP Made) → Pyruvate to Acetyl CoA (0) → Kreb Cycle(2) → ETC (34)

ETC (stand for?)

Electron Transport Chain

cytrochromes

proteins that transport electrons

electrochemical gradient

electrical gradient - the charge

chemical gradient - the concentration of H+ (the protons)

THE ETC breakdown

electrons are transferred from NADH and FADH2 to travel through the membrane by cytochromes. Once they travel, H+ are being pumped out from the matrix to the intermembrane space which creates an electrochemical gradient.

WHY? - there is a higher concentration of protons on the intermembrane space than in the matrix. Also, the charge in the intermembrane space is more positive than in the matrix.

The H+ diffuse back into the matrix (chemiosmosis) through ATP synthase, which is a channel and enzyme that creates ATP. When the H+ go through the ATP synthase channel, the channel gets charged and oxidative phosphorylation occurs. Phosphates are attached to ADP to make ATP. H+ that go through the channel are picked up by the final electron acceptor (oxygen) to create WATER.

where does the ETC occur?

The intermembrane system. (b/w the inner membrane and the matrix)

What is the final electron acceptor in the ETC chain?

oxygen

Chemisosmosis

Diffusion of H+ DOWN their concentration gradient.

if ATP synthase wasn’t there, why cant H+ move back into the matrix?

the membrane is IMPERMEABLE to H+

Oxidative Phosphorylation

when ATP synthase produces ATP. the energy comes from the ORIGINAL glucose oxidation process.

Substrate-level phosphorylation

directly adding a phosphate to ADP to make ATP

What is the function of Chlorophyll?

its a pigment that absorbs all light but reflects green for photosynthesis.

Photosynthesis

the conversion of light energy to chemical energy.

Plants can use what light for photosynthesis? (in order from best to worst)

blue, violet, red, orange

they can die from green/yellow (prevents them from performing photosynthesis).

When you see/hear Chlorophyll think of

double peaks!

what macromolecule is chlorophyll?

Chlorophyll

Where does photosynthesis occur?

In the chloroplasts

Chloroplasts (picture)

Membrane:

• outer

• inner

• thylakoid

Compartments (spaces):

• intermembrane space

• stroma

• thylakoid space

What is the final electron acceptor in the chloroplasts?

NADP+

Photolysis

splitting of water to return elections back to chlorophyll.

How many reactions are in photosynthesis

2: light and dark reaction

Ingedients of the light reaction

light, H2O, CO2 → C6H12O6 +6O2

Ingredients of the Dark reaction

light, H2O + CO2 → C6H12O6 + 6O2

What reaction needs to happen first before the other does?

The light reaction needs to happen first before the dark reaction.

Calvin Cycle (Dark Reaction) break down

6 CO2 (from the light cycle) + 6 RuBP + Rubisco(enzym) → 12 PGA

PGA → (12 ATP is oxidized to 12 ADP and 12 NADPH is oxidized to 12 NADP+) → 12 PGAL

10 PGAL goes baack and is turned into 6 RuBP to repeat the process while the other 2 PGAL is turned back into glucose

In the dark reaction, where does the 12 NADP+ go ?

They get reused in the light reaction

Where does the light reaction occur?

the thylakoid membrane

Where does the dark reaction occur?

the stroma