Cellular Respiration

Glycolysis – In the cytosol

Uses 2 ATP’s

Makes 4 ATP’sMakes 2 NADH’s

Left with 2 pyruvates

Start with Glucose

Glycolysis - in the cytosolNOTICE THE SPLITTING HERE!EVERYTHING FOLLOWNG MUST BE MULTIPLIED BY 2!

Pyruvate to the mitochondria

Kreb’s Cycle – in the mitochondrial matrix

Electron Tranport Chain (detailed)

ATP synthase in mitochondria – virtual animation

Electron Transport Chain – virtual animation

Where do the electrons come

from?

ATP synthase allows for

chemiosmosis

Reactions in Respiration

Inputs• Glycolysis (cytoplasm)

Glucose 2ATP 4ADP 2NAD+

• Krebs Cycle (mitochondria) Pyruvate NAD+

CoA FAD ADP

Outputs• Glycolysis (Cytoplasm)

2ADP 4ATP 2NADH 2 pyruvate

• Krebs Cycle (mitochondria) NADH CO2

FADH2

ATP

Reactions in Respiration (cont.)

Inputs• Electron Transport Chain in

mitochondria membraneNADHFADH2

O2

Outputs• Electron Transport Chain in

mitochondria membrane– NAD+

– FAD– ATP

– H2O

Cellular Respiration Summary

3 Basic Steps:1) Glycolysis (in the cytoplasm)

2) Kreb’s Cycle (inner mitochondrial space)

3) Electron Transport Chain (mitochondrial membrane)

C6H12O6 + O2 CO2 + H2O + ATP

glucose pyruvate + ATP + NADH

pyruvate NADH + FADH2 + ATP + CO2

NADH + FADH2 + O2 ATP + H20

Photosynthesis

Light + CO2 + H2O C6H12O6 + O2

Respiration

C6H12O6 + O2 CO2 + H2O + ATP

Inputs Outputs

Reactions in Photosynthesis (Chloroplast)

Inputs• Light Dependent Reactions in

the Thylakoid Light H2O

NADP+ ADP

• Calvin Cycle in the Stroma ATP CO2

NADPH

Outputs• Light Dependent Reactions in

the Thylakoid O2

NADPH ATP

• Calvin Cycle in the Stroma ADP NADP+ Glucose (C6H12O6)

Light Reaction … light energy shakes chlorophyl … releases electons

In the Thylakoid

In the Stroma• The ATP and

NADPH was made during the light reactions (thylakoid)

• CO2 enters the cycle at top

• Glucose / Organic compounds are the output

Review – Big Picture

Sunlight to ATP

Big Picture Review

chloroplast

H2O

O2

NADPH

StromaThylakoid

CO2

Glucose

Glycolysis (cytoplasm)

pyruvate

CO2

NADH

mitochondria

Kreb’s CycleNADH

FADH2

Electron Transport

ATP

H2O

ATP

ATP

ATP

Photosynthesis and Respiration work together!

• Matter is cycled within these two processes

• Energy flows through these two processes

• Sunlight provides the energy that eventually becomes ATP in you

What’s ATP?

What’s ATP used for?• ATP is the

spending money of the cell

• It allows for other molecules to be phosphorylated

• Phosphorylation allows for transport work, mechanical work, and chemical work

Redox Reactions

• Carbon is oxidized by Oxygen (oxidizing agent)• Oxygen is reduced by Carbon (reducing agent)

Why does the food we eat not immediately combust in our bodies?

• Many, many, many, many steps taken to release the energy!

• Glycolysis• Kreb’s cycle• ETC

• This insures we don’t blow up from our food being oxidized too quickly!

No oxygen = anaerobic pathway

• Yeast/bacteria– Produce ethanol

when deprived of oxygen … still has some energy

• Humans– Produce lactic acid

when deprived of oxygen

– Recycled in liver to produce pyruvate

Anaerobic Respiration• Without Oxygen

– No electron transport chain … less ATP

• 2 types:

1) Alcoholic fermentation: (bacteria, yeast)

Pyruvate + NADH Ethanol + NAD+ + CO2

2) Lactic Acid fermentation: (animals like you)

Pyruvate + NADH Lactic Acid + NAD+

What’s different about these two equations?

How can you set up an experiment to detect the difference?

Catabolic Pathways

• Note: it’s not just carbohydrates (glucose) that gets converted into ATP

• What happens to proteins?

• What happens to fats?

Control of Respiration … feedback systems

• Lots of AMP (low energy molecule)– Stimulates enzyme to

produce ATP

• Lots of ATP or Citrate– Shuts down enzyme to

prevent overproduction