Cellular Respiration

Question 1

Cellular respiration

Answer 1

an ATP generating process that occurs within cells. Energy is extracted from energy rich glucose to form ATP from ADP and P. The chemical equation is
C6H12O6 + 6O2 -> 6CO2 + 6H2O + energy

Question 2

Aerobic respiration

Answer 2

cellular respiration in the presence of O2. It is divided into three components: glycolosis, the Krebs cycle and oxidative phosphorylation.

Question 3

Glycolosis

Answer 3

the decomposition of glucose to pyruvate. Nine intermediate products are formed. and each one is catalyzed by an enzyme. Mg2+ are cofactors that promote enzyme activity.

Question 4

Glycolosis Steps

Answer 4

1) 2 ATP are added: First several steps require energy input. This changes glucose in preparation for subsequent steps.
2) 2 NADH are produced. NADH, a coenzyme, forms when NAD+ combines with the two energy rich electrons. and H+ (obtained from an intermediate). As a result NADH is an energy rich molecule.
3) 4 ATP are produced
4) 2 pyruvate are formed
Summary: glycolosis takes 1 glucose and turns it into 2 pyruvate, 2 NADH adn a net of 2 ATP. Occurs in cytosol.

Question 5

The Krebs Cycle

Answer 5

details what happens to pyruvate the end product of glycolosis.
3 NADH, 1 FADH2, 1 ATP AND CO2.
Begins with acetyl CoA combines with OAA to form citrate. There are seven intermediate products along the way. 3 NADH and 1 FADH2 are made and CO2 released.
also known as Citric acid cycle and TCA cycle
occurs in mitochondria

Question 6

Step leading to Krebs cycle

Answer 6

1) Pyruvate to acetyl CoA.: In a step leading up to the actual Krebs cycle, pyruvate combines with coenzyme A (CoA) to produce acytal CoA. In that reaction 1 NADH and 1 CO2 are also produced.

Question 7

OAA

Answer 7

oxaloacetate

Question 8

FADH2

Answer 8

like NADH is a coenzyme, accepting electrons during a reaction

Question 9

CO2 from Krebs Cycle is

Answer 9

the CO2 animals exhale when they breathe.

Question 10

Oxidative Phosphorylation

Answer 10

the process of extracting ATP from NADH and FADH2. Electrons from NADH and FADH2 pass along an electron support chain. The final electron acceptor of the ETC is oxygen. The 1/2 O2 accepts the two electrons and together with 2 H+ forms water.
occurs in mitochondria

Question 11

Electron transport chain

Answer 11

the chain consists of proteins that pass these electrons from one carrier protein to the next. Along each step of the chain the electrons give up energy used to phosphorylate ADP to ATP.

Question 12

How much ATP can be produced from NADH

Answer 12

it produces enough electrons to produce 3 ATP

Question 13

FADH2 produces enough electrons to produce __ ATP

Answer 13

2 ATP

Question 14

Cytochrome C

Answer 14

one of the carrier proteins (includes iron) in the ETC is so ubiquitous among living organisms that approximately 100 amino acid sequence of the protein is often compared among species to access genetic relations

Question 15

Mitochondria distinct areas

Answer 15

Outer membrane, intermembrane space, inner membrane, matrix

Question 16

Outer membrane of mitochondria

Answer 16

this membrane is like the plasma membrane consists of a double layer of phospholipids

Question 17

Intermembrane space of mitochondria

Answer 17

this is the narrow area between the inner and outer membranes. H+ ions (protons) accumulate here

Question 18

Inner membrane of mitochondria

Answer 18

the second membrane, also a double phospholipid bilayer, has cristae. Oxidative phosphorylation occurs here. Within the membrane and its cristae the electron transport chain removes electrons from NADH and FADh2 and protein complexes transports H+ ions from the matrix to the intermembrane space.

Question 19

Matrix

Answer 19

the matrix is the fluid material that fills the area inside the inner membrane. the Krebs Cycle and the conversion of pyruvate to acetyl CoA occur here.
-The Krebs cycle produces NADH and FADH2 in addition CO2 is generated and substrate level phosphorylation occurs to produce ATP.

Question 20

Chemiosmosis

Answer 20

the mechanism of ATP generation occurs when energy is stored in the form of a proton concentration gradient across a membrane

Question 21

ATP synthase generates ATP in mitochondria explain

Answer 21

ATP synthase a channel protein in the inner membrane, allows the protons in the intermembrane compartment to flow back into the matrix. The protons moving through the channel generate the energy for ATP synthase to produce ATP.

Question 22

how pH is created in mitochondria

Answer 22

as H+ are transferred from the matrix to the intermembrane space, the concentration of H+ increase (and pH decreases) in the intermembrane space and decreases in the matrix (pH increases)

Question 23

Two types of phosphorylation

Answer 23

substrate level and oxidative, two metabolic processes for generating ATP occur

Question 24

Substrate level phosphorylation

Answer 24

occurs when a phosphate group and its associated energy is transferred to ADP to form ATP. the substrate molecule (molecule within the substrate group) donates the high energy phosphate group. Occurs in glycoyisis

Question 25

Oxidative phosphorylation

Answer 25

occurs when a phosphate group is added to ADP to form ATP but the energy for the bond does not accompany the phosphare group. Instead the ETC supplies the engery.

Question 26

Anaerobic respiration

Answer 26

the method cells use when there is no oxygen present and no electron acceptor exists to accept electrons at the end of ETC ceasing Krebs cycle and glycolosis. Occurs in the cytosol. two metabolic pathways are alcohol and lactic acid fermentation.

Question 27

Alcohol fermentation (fermentation)

Answer 27

occurs in plants, fungi (yeasts) and bacteria

1) pyruvate to acetaldehyde. for each pyruvate 1 CO2 and 1 acetalhyde are produced, the CO2 formed is the source of carbonation in fermented drinks like beer and champagne
2) acetaldehyde to ethanol. the important part of this step is the energy in NADH is used to drive this reaction releasing NAD+. For each acetaldehyde, 1 ethanol is made and 1 NAD+ is produced

Question 28

Lactic Acid fermentation

Answer 28

A pyruvate is converted to lactate, and in the process, NADH gives up its electrons to form NAD+, as in alchohol fermentaion, the NAD+ can now be used as glycolysis. In animals most lactate is transported to the liver where it is converted back to glucose when surplus ATP is available.