Cellular Respiration

what is glucose and how is it used to create ATP

glucose is a simple sugar, it is a molecule that contains high amounts of energy.

-it is oxidized, removing a hydrogen ion and an electron to create a more usable form called ATP

what is glycolysis

the process of breaking down glucose (6-carbon molecule) into two pyruvate(3-carbon molecule)

mitochondria

an organelle where the site of cellular respiration occurs

what is the outer and inner membrane of mitochondria

outer- a permeable membrane only to substances needed for CR

inner- folded membrane containing electron transport systems(where atp synthesis occurs)

cristae

folded parts in the inner membrane that increase the surface area for production of atp

matrix

central region containing gel-like fluid

-contains enzymes for the oxidation of glucose, lipids, and proteins

what is the first step of cellular respiration

1. glycolysis occurs, happens in the cell’s cytoplasm

   -2 atp activates glucose, splitting it into two intermediate 3-C molecules

   -it goes through chemical reactions converting it into two pyruvate

   -during this process, 4 atp and 2 nadh is formed

What is the overall purpose of cellular respiration?

to break down glucose and produce ATP for cellular activity

What are the 4 main stages of cellular respiration (aerobic)?

1. glycolysis

2. pyruvate oxidation

3. krebs cycle/citric acid cycle

4. electron transport chain

where does glycolysis occur

in the cell’s cytoplasm

what are the products for glycolysis

-2 pyruvates

-1 nadh

-2 atp

What happens during pyruvate oxidation?

pyruvate is combined with coenzyme a to form acetyl CoA

-released C02, acteyl molecule oxidizes, donating its electron to NAD→NADH

where does the kreb’s cycle take place

in the matrix of the mitochondria

What are the products of one turn of the Krebs Cycle?

3 NADH, 1 FADH₂, 1 ATP, 2 CO₂

What is the role of NADH and FADH₂?

it is to carry high energy electrons to the electron transport chain

what happens in the ETC?

electrons pass through protein complexes/electron-carrying molecules, the energy powers hydrogen ion movement from matrix to intermembrane space, creating a gradient for atp production

What is the final electron acceptor in the ETC?

oxygen accepts the electrons and hydrogen, creating h20

what is fermentation

a metabolic process that breaks down sugars to acids,gases, or alcohol

-regenerates NAD+ allowing glycolysis to continue

describe the two types of fermentation

1. ethanol fermentation

   -occurs in bacteria+yeast cells

   -after glycolysis, pyruvate goes through decarboxylation removing c02, converting it into 2 ethanol and 2 c02

   -NADH is used to reduce pyruvate, regenerating NAD

2. lactate fermentation

   -occurs in animal cells(ex. muscles)

   -after glycolysis, pyruvate is reduced by NADH, forming lactic acid

   -NAD is regenerated

   -build up of lactic acid=muscle burn/cramps

what is decarboxylation

the process of losing c02 from a compound