Atp/Metabolism

Question 1

What is Metabolism ?

Answer 1

Sum of Chemical reactions which take place within each cell of a living organism/providing energy for vital processes and synthesis organic material .

Question 2

How are Bonds formed ?

Answer 2

Through dehydration synthesis

Anabolic reactions use up energy , they are endergonic .For example amino acid form to make dipeptide

Question 3

How are Bonds broken ?

Answer 3

Through hydrolysis in which H20 is added

Catabolic reactions in which energy is released and they are exergonic .

Large molecules are broken down into smaller ones .

This includes , the conversion of glucose during respiration to produce carbon dioxide .

Question 4

What is Exergonic reaction ?

Answer 4

Energy is realised from the surroundings .

The bonds being formed are stronger than the bonds being broken .

Question 5

What is Endergonic Reactions ?

Answer 5

Energy is absorbed to the surroundings .

The bonds being formed are weaker than the bonds being broken .

Building polymers more organisation , higher energy state .

Question 6

What is the inhibition of enzyme activity ?

Answer 6

Some substances reduce or even stop the catalytic activity of the enzymes in biochemical reaction

They block or disrupt the active site .These chemical are called inhibitors .

Question 7

What are competive inhibitors ?

Answer 7

Inhibitors/substrate they compete for active site.
Penicillin
Blocks enzymes bacteria use to build cell wall

Disulfiram (Antabuse)
Treats chronic alcoholism
Blocks enzymes that break down alcohol.
Severe hangover /vomiting 5-10 after drinking

Overcome by increasing the substrate concentration .
Saturate solution with substrate so it can competes inhibitor for active site on enzyme .

Question 8

What are non-completive inhibitors ?

Answer 8

They attach to other parts of the enzyme molecule ,distorting their shape they are known as non-completive /non active site directed

Question 9

What are non-completive inhibitors?

Answer 9

Binds to site other than the active site
Causes the enzyme to change shape
Allosteric inhibitor bonds to allosteric site.
Allosteric inhibitor change the shape of enzyme so it cannot bind to substrate
Conformational shape
Active site is no longer functional binding site keeps the enzyme active

Some anti-cancer drugs
Inhibit enzymes involved in DNA synthesis

Question 10

What are coenzymes ? and cofactors?

Answer 10

Many enzymes require special molecules to help them function correctly:
Cofactors:
inorganic molecules ions, such as zinc or iron

Coenzymes
organic molecules

Question 11

Allosteric ?

Answer 11

allo” = other; “steric” = shape

binding to an allosteric site changes the shape of the enzyme and affects its function

Question 12

Give an example of non-competive ?

Answer 12

cyanide poisoningirreversible inhibitor of Cytochrome C, an enzyme in cellular respiration
stops production of ATP

Question 13

What is Cellular Respiration ?

Answer 13

Cellular Respiration is a metabolic pathway that breaks down glucose and extracts the energy to produce energy

Most efficient route for generation of ATP

Question 14

What is the oxidation of glucose ? Stages

Answer 14

The complete aerobic oxidation of glucose is coupled to the synthesis of as many as 36 molecules of ATP.

Question 15

Where does the Kreb cycle occur ?

Answer 15

Mitochondria

No not all living organism go through the kerb cycle only those in eukaryotes.

Question 16

1 step of the cycle

Answer 16

1. Glycolysis occurs , this occurs in the cytoplasm.
   Two sugars are split in the cytoplasm
   Two ATP transfer energy to the glucose molecule forming a 6 bi phosphate fructose molecule .Splits

Question 17

2 second step of the cycle

Answer 17

The molecules are converted to pyruvate what is known as processing of the pyruvates forming an ATPin the process of glycolysis .

2ATP
2 NaDH
2 Pyruvates

When oxygen is present the two pyruvates , NADH molecules enter the mitochondria.

Question 18

3 Celluar respiration

Answer 18

The movement of the two pyruvates into the mitochondria where oxidation occurs.

Each pyruvate is converted into a compound known as Acetyl coA.

In this process of pyruvate oxidation electrons are transferred to NAD producing a carbon which is lost forming c02

Question 19

Citric acid/kerb cycle 4 step

Answer 19

Acetyl CoA will bind with oxaloacetate to form citrate and through a series of enzymatic redox reaction all carbons , hydrogens and oxygen’s in pyruvate end up as C02 /h20

Question 20

5 step

Answer 20

The pathway repeats two times

During pyruvate oxidation, and the citric cycle a net of 8 NadH2, 2 FaDH, 2 ATP and 6c02 are produced for each glucose.

Question 21

Electron Transport Chain?

Answer 21

Series of membrane bound carriers in the mitochondria that passes electrons from one to another .

As the electrons are transferred between the membrane proteins and the cell is able to capture energy and use it to produce ATP molecules .

Proteins inside the chain pump hydrogen ions across a membrane , when the hydrogen ions flow back, through the ATP synthase complex ATP is synthesises by the enzyme ATP synthase

Oxygen acts the electron acceptor , oxygen is reduced to form water by a product of the electron transport chain .

All electron carriers from the previous stages of cellular respiration bring their electrons into the chain from the bulk of ATP from the energy of cellular respiration is produced a net to 32-36 ATP is produced .

Question 22

What are the electrons carried process to etc?

Answer 22

10 NADH

2 FADH2

Question 23

What is oxidative phosphorylation ?

Answer 23

Process in which ATP os formed as a result of the transfer of electrons from NADH or FADH2 to 02 by electrons carriers process takes place in the mitochondria .

Question 24

What would reducing NADH or FADH2 used for?

Answer 24

Used for cooperation of 2 processes.
Electron transport chain
Chemiosis (movement of ions across a secretory permeable membrane , down their electrochemical gradient.)

Question 25

What is the electron transport chain ? What happens

Answer 25

These carriers then donate electrons and protons to the electron carrier proteins of the electron transport chain.
The final electron acceptor is oxygen. Together with oxygen, electrons and protons form molecules of water

function of the electron transport chain is to produce a transmembrane proton electrochemical gradient as a result of the redox reactions. If protons flow back through the membrane, they enable mechanical work, such as rotating bacterial flagella.

it can only take place when oxygen is present because it relies on by-products from the electron transport chain, which requires oxygen. The Krebs cycle is therefore an aerobic process.

If there is no oxygen in an electron transport chain then there will be no aerobic respiration that means no electron transport chain phase

Question 26

How is 38 ATP produced ?

Answer 26

During cellular respiration, total energy produced is 38 ATP.

Two processes take place during cellular respiration- glycolysis and krebs cycle. In the mitochondrion, glucose is completely broken down into carbon dioxide and water and 36 ATP. So total ATP produced is 38 ATP.

Question 27

Electron transport chain and Chemiosmosis ?

Answer 27

Together, the electron transport chain and chemiosmosis make up oxidative phosphorylation.

Question 28

Cyanide acts as a poison because it inhibits complex IV, making it unable to transport electrons. How would cyanide poisoning affect 1) the electron transport chain and 2) the proton gradient across the inner mitochondrial membrane?

Answer 28

The electron transport chain would stop, and the gradient would decrease