Lecture 8: Cellular Respiration Flashcards
What is the main product of cellular respiration?
ATP, adenosine triphosphate.
How does ATP release energy?
ATP releases energy when it drops a phosphate group converting to ADP.
Why do cells need energy?
Cells need energy to complete routine functions such as transport of material, building of organelles, mechanical work.
How does the mitochondria support endomembrane theory?
Because it has its own DNA, mtDNA. As well as its own ribosomes.
Describe the structure of the mitochondria, draw it.
The mitochondria consists of two membranes and an intermembrane space. The outside membrane is called the outer mitochondrial membrane the inside is called the inner mitochondrial membrane. The inner mitochondrial membrane is folded into a structure called cristae which increases surface area. Inside all of the membranes is the mitochondrial matrix.
What is the first process of cellular respiration?
Glycolysis which occurs in the cytosol outside of the mitochondria. Here is when glucose is split into two smaller three carbon molecules called pyruvate. NAD+ is also produced into NADH a high energy electron carrier. 2 ATP is produced.
What is the second stage of cellular respiration called?
Pyruvate Oxidation + Citric Acid Cycle.
In pyruvate oxidation, pyruvate is oxidised into acetyl coa. CO2 is produced as a biproduct.
In the citric acid cycle the acetyl coa enters and undergoes a series of reactions. The end product is some ATP, NADH and FADH2 another high energy electron carrier. Some more CO2 is produced. These stages occur within the mitochondrial matrix.
What is the final stage of cellular respiration called?
Oxidative Phosphorylation which can further be split into two stages called the electron transport chain and chemiosmosis. In the electron transport chain FADH2 and NADH travel through proteins embedded in the inner mitochondrial membrane. The energy released causes protons to travel across the concentration gradient and into the inter membrane space. During this oxygen is converted into water.
Chemiosmosis then occurs when the protons travel back into the mitochondrial matrix down there concentration gradient through ATP synthase. When this occurs ATP is created.
