Cellular respiration flashcards

It is a process cells use to release energy needed for all kinds of work (Ex: used during muscular contraction). The two types are aerobic which requires O2 and Anaerobic which doesn't require O2 (aerobic is more efficient 36 ATP vs 2 ATP made). The word formula is C6H12O6 + 6O2 -> 6CO2 + 6H2O + ATP. During respiration chemical bonds of reactant food molecules are broken and newbons creat new product, it is considered an energy releasing process because more E is released than consumes to break reactant molecules, it is 36% efficient (36% of glucose energy is converted into ATP) the rest is released as heat.

NADH made from NAD⁺ + H⁺, FADH2 made from FAD⁺ + 2H⁺, ATP made from ADP + Pi. NADH and FADH2 act as electron carriers for cell resp. and ATP is used as a source of energy. The transfer of e- from the carriers produces more stable ions/compounds and releases energy this can be used to make ATP and power other processes, the released electron will be put into an ETC.

1 human cell contains about 1 billion ATP molecules, ATP gives the energy required for active transport (powers pumps to move things against concentration gradient), ATP is also used for muscular contraction, beating of cillia and flagella, cytoplasmic streaming/movement of organelles, building molecules, allosteric activity and bioluminesence.

The four stages are 1. Glycolysis, 2. Pyruvate Oxidation, 3. Krebs Cycle, 4. ETC and chemiosmosis. The overall equation is C6H12O6 + 6O2 + 36ADP + 36Pi -> 6CO2 + 6H2O + 36ATP (36 average).

It is cellular respiration that occurs in the absence of O2 and glucose is not completely oxidized. There are 2 types of anerobic (plant and animal) cellular respiration and both types have two stages which are 1. glycolysis and 2. fermentation. The plant one makes ethanol while the animal one makes lactic acid. Fermentation occurs in the cytoplasm after glycolysis and has 2 stages.

Glycolysis in the cytoplasm of all cells. It is an anaerobic process that uses 2 ATP to make 4 ATP (2 ATP net gain) and 2 NADH⁺ and it turns 6 carbon glucose into two three carbon pyruvate. First two phosphates from two ATPS are added to glucose, second, the glucose is turned into two PGAL which are oxidized and turned into 2PGA, NAD⁺ acts as the oxidizing agent and becomes NADH and the energy released makes ATP, Third you make two more ATP from the 2 PGA which then become 2 pyruvic acid. Glycolysis is not efficient only 2.2% of availible energy in glucose is transferred to ATP most E remains in 2 pyruvate and 2 NADH, but some single cellular microorganisms can live off just glycolysis.

The top structures are Cristaethen Matrix. then the right side top to bottom is matrix then cristae. Then left is outer membrane then middle bottom in intermembrane space then right bottom is inner membrane.

It specializes in the production of ATP in Eukaryotic cells. It has a smooth outer membrane which is semi permeable and a highly folded inner membrane which performs cellular respiration. The intermembrane space is the fluid filled space between the inner and outer membrane, The inner membrane creates two compartments within the mitochondria and the folds are called christae, and the mitochondrial matrix is the protein rich liquid that fills the innermost space (inner membrane)

Pyruvate oxidation, which "preps pyruvate for the mitochondria". 2 pyruvate molecules are moved through 2 mitochondrial membranes into the matrix. There are 3 steps CO2 removal, Acetic acid formation and Co-enzyme A + acetic acid = acetyl CoA. In the first step 2 pyruvate is decarboxylated and 1/3 of this CO2 is breathed out as waste. Step two, Acetic Acid forms after the remaining 2 carbon portions are oxidized by 2NAD+ which turns into 2NADH, these will go to stage 4 of aerobic respiration and the remaining compound becomes acetic acid. Third CoA will attach and it will form 2 acetyl CoA.

The Krebs cycle or Citric acid cycle happens in the mitochondrial matrix. It occurs 2 times for every glucose molecule (because theres 2 acetyl CoA). It begins when acetyl CoA condenses with oxaloacetate to form citric acid (2x). Then over the cycle the two carbons from acetyl CoA will be cleaved off, which regenerates oxaloacetate. 3 NADH are produced from NAD+, 1 FADH2 from FAD and 1 ATP from the energy and oxidation of the carbons, x2 because 2 acetyl CoA.

Electron transport and Chemiosmosis. NADH and FADH2 transfer H atom electrons to a ETC within the inner mitochonddial membrane. First 1 NADH gives up 2e- at the beggining of ETC and the H+ is released into the matrix then FADH2 does later which is why it has less E and powers less H+ pumps. As the e- moves it gives energy which forces H+ from within the matrix across inner membrane into the intermembrane space. O2 is the final electron acceptor at the end of the ETC and joins with H+ to make H2O.

WHile H+ pumps move H+ from the matrix, through the inner membrane and into the intermembrane space an electrical gradient builds up. Then the H+ move through the ASC via chemiosmosis to balance charges and pwoer ATP production (done by an enzyme).

1 NADH pumps enough H+ to generate 1-3 ATP. 1 FADH2 pumps enough H+ to generate 1-2 ATP. O2 receives the electron from etc and ATP is moved into the cytoplasm of the cell

2 NADH is made during glycolysis and 2 ATP, 2 NADH is made during pyruvate oxidation, 6 NADH, 2 FADH2 and 2 ATP (alr x2) is made during the krebs cycle, and 32 ATP is made during ETC/chemiosmosis. The Amount of ATP produced by cellular respiration can vary from 30-38 but the amount of energy packmule produced stays constant.

In plants alcohol fermentation occurs.  NADH's from glycolysis pass H atoms to acetaldehyde which is made when 2 CO2 is removed from 2 pyruvate using pyruvate decarboxylase this produces acetaldehyde which is then made into 2 ethanol. The NAD from NADH will be recyled and glycolysis will continue.

Under normal conditions animals obtain E from glucose by aerobic cellular respiration, but sometimes more ATP is needed like during exercise so lactic acid fermentation will supply this additional ATP. NADH from glycolysis will transfer H+ atoms to pyruvate, which will turn pyruvate into lactic acid and NADH into NAD+ which will be reused in glycolysis. The accumulation of lactic acid causes muscle stiffness, soreness and fatigue to stop this O2 must be used to process lactic acid back into pyruvate which results in oxygen debt and panting.