cellular respiration n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Cellular Respiration PowerPoint Presentation
Download Presentation
Cellular Respiration

Loading in 2 Seconds...

play fullscreen
1 / 39

Cellular Respiration - PowerPoint PPT Presentation


  • 69 Views
  • Uploaded on

Cellular Respiration. Identify major stages of the process Location of each stage Describe structures Illustrate with simple diagrams Indicate how ingredients are acquired/products released Factors that affect the rate of respiration. The stages.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Cellular Respiration' - aimee


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
cellular respiration
Cellular Respiration
  • Identify major stages of the process
  • Location of each stage
    • Describe structures
    • Illustrate with simple diagrams
    • Indicate how ingredients are acquired/products released
  • Factors that affect the rate of respiration
the stages
The stages
  • Group learning: what is respiration? General information & description.
  • Become an expert on one part of the process
  • Educate your group members
  • Collaborate and sync up the entire process
  • Make connections & compare
  • The BIG picture! Connect with photosynthesis

The Processes

Anaerobic respiration: Compare energy efficiency with aerobic respiration

Glycolysis

Krebs Cycle (aka Citric Acid Cycle)

Electron Transport Chain

Factors that affect the rate of respiration

resources
Resources
  • Online text & animations
  • Class notes linked to Mrs. DeNicola’s website
  • Animations on “AP Bio Links” page
  • Chapter 7 Review questions
  • Energy packets
where we last left off
Where we last left off:

**Glucose made as a byproduct of photosynthetic reactions

  • Harvesting stored energy…
  • Energy stored in organic molecules
    • carbohydrates, fats, proteins
  • Heterotrophs eat food
    • digestive results…
      • raw materials for synthesis
      • fuels for energy
        • controlled release of energy
        • “burning” fuels occurs inseries of step-by-step enzyme-controlled reactions
slide6

glucose + oxygen  energy + water + carbon

dioxide

respiration

+ heat

ATP

+

+

6CO2

6H2O

+

C6H12O6

6O2

ATP

glucose

O2

  • Glucose is the treasure chest
    • catabolizeglucose to produce ATP

RESPIRATION = making ATP (& some heat)by burning fuels in many small steps

ATP

enzymes

CO2 + H2O + ATP (+ heat)

slide7

e

p

loses e-

gains e-

oxidized

reduced

+

+

+

H

oxidation

reduction

H

+

6CO2

+

+

ATP

C6H12O6

6O2

6H2O

H

How do we harvest energy from fuels?

  • Food digestion = bond breaking & electron movement (energy carrying)
  • Electron movement
    • NOT alone → move as part of H atom

oxidation

reduction

e-

slide8

O–

O–

O–

O–

P

P

P

P

–O

–O

–O

–O

O–

O–

O–

O–

O

O

O

O

NAD+

nicotinamide

Vitamin B3

niacin

O

O

H

H

C

C

NH2

C

C

NH2

N+

N+

reduction

+

H

oxidation

phosphates

adenine

ribose sugar

Ele- Movement in Respiration

  • Electron carriers move ele-by shuttling H atoms
    • NAD+NADH (reduced)
    • FAD+2FADH2 (reduced)

reducing power!

NADH

H

carries electrons as a reduced molecule

overview of cellular respiration

+

ATP

+

+

6CO2

C6H12O6

6O2

6H2O

Overview of cellular respiration
  • 4 metabolic stages
    • Anaerobic respiration (NOO2)

1. Glycolysis

        • in cytosol
    • Aerobic respiration (O2)
        • in mitochondria

2. Pyruvate oxidation

3. Krebs cycle

4. Electron transport chain

(+ heat)

1 glycolysis

glucose      pyruvate

6C

3C

2x

1. Glycolysis
  • “glyco – lysis” (splitting sugar)
    • Pathway observed in nearly ALL organisms
      • Speculated as one of oldest pathways, most fundamental
      • WHY?
    • Inefficient
      • For every 1 glucose generate only2 ATP

That’s not enoughATP for me!

overview

enzyme

enzyme

enzyme

enzyme

enzyme

enzyme

enzyme

ATP

ATP

2

4

2

2

4

NAD+

ADP

ADP

2Pi

2

2Pi

2H

Overview

glucose

C-C-C-C-C-C

10 reactions

  • convert glucose (6C)to 2 pyruvate (3C)
  • produce:4 ATP & 2 NADH
  • consumes:2 ATP
  • NET YIELD: 2 ATP & 2 NADH

fructose-1,6bP

P-C-C-C-C-C-C-P

G3P x2

C-C-C-P

G3P x2

P~C-C-C-P

Pyruvate x2

C-C-C

G3P = glyceraldehyde-3-phosphate

feedback control
Feedback control
  • Why use excess when its not needed?
    • [ATP] activates/inactivates control enzyme (phosphofructokinase)
    • Enzyme used to make phosphorylated glucose
    • Allosteric regulation!!!
    • 2 active sites
      • 1. forms phosphorylated glucose
      • 2. conformation change  inactivate
slide13

Is this enough to support life?

O2

O2

O2

O2

O2

  • Not a lot of energy…
    • for 1 billon years+ life on Earth survived this way
      • no O2 = slow growth, slow reproduction
      • only harvest 3.5% of energy stored in glucose
        • more carbons to strip off = more energy to harvest

O2present

Onto the Krebs Cycle!!!

mitochondrial structure review

outer

membrane

intermembrane

space

inner

membrane

cristae

matrix

mitochondrialDNA

MitochondriaLStructure Review
  • Double membrane
    • smooth outer membrane
    • highly folded inner membrane
      • cristae
    • intermembrane space
      • fluid-filled between membranes
    • matrix
      • inner fluid-filled space
    • DNA, ribosomes
    • enzymes
      • free in matrix & membrane-bound
slide16

Prepping for Krebs: formation of Acetyl CoA

NAD+

2 x [

]

reduction

Acetyl CoA

Coenzyme A

CO2

Pyruvate

C-C

C-C-C

oxidation

Yield = 2C sugar + NADH + CO2

(Acetyl CoA)

2 krebs cycle

1937 | 1953

2. Krebs cycle
  • aka Citric Acid Cycle
    • in mitochondrial matrix
    • 8 step pathway
      • each catalyzed by specific enzyme
      • step-wise catabolism of 6C citratemolecule (stripping out the carbons)
  • Appeared later than glycolysis – WHY?

Hans Krebs

1900-1981

slide18

2C

6C

5C

4C

3C

4C

4C

4C

4C

6C

CO2

CO2

Count the carbons!

pyruvate

acetyl CoA

citrate

oxidationof sugars

This happens twice for each glucose molecule

**Process regulated by + and – feedback control by [ATP]!!!**

x2

slide19

2C

6C

5C

4C

3C

4C

6C

4C

4C

4C

NADH

ATP

CO2

CO2

NADH

FADH2

NADH

Count the electron carriers!

pyruvate

acetyl CoA

citrate

reductionof electroncarriers

This happens twice for each glucose molecule

x2

slide20

How’s our savings?

  • Fully oxidized
  • C6H12O6
  • CO2
  • NET YIELD:(3 NADH) x 2(1 ATP) x 2(1 FADH2) x 2
  • 6 NADH
  • 2 ATP
  • 2 FADH2
let s recap
Let’s Recap…
  • Glycolysis2ATP
  • Kreb’s cycle 2ATP
  • Life takes a lot of energy to run, need to extract more energy than 4 ATP!
      • Fun Fact!!!

I need a lotmore ATP!

A working muscle recycles over 10 million ATPs per second

3 the etc
3. The ETC!!!
  • Proteins built into inner mitochondrial membrane
    • along cristae
    • transport proteins& enzymes
  • In presence of O2
  • Ele- shuttled (by NADH & FADH2)down ETC pump H+ to create H+ gradient → chemiosmosis!!!
  • yields ~36 ATP from 1 glucose!
the players

Innermitochondrialmembrane

The Players…

Intermembrane space

C

Q

Enzyme

Enzyme

Enzyme

Mitochondrial matrix

Cytochromes used for making H+ gradient

slide24

e

p

1

2

Let’s Follow the Chain…

Building proton gradient!

NADH  NAD+ + H

intermembranespace

H+

H+

H+

innermitochondrialmembrane

H  e- + H+

C

e–

Q

e–

H

e–

FADH2

FAD

H

NADH

2H+ +

O2

H2O

NAD+

Enzyme

Enzyme

Enzyme

mitochondrialmatrix

What powers the proton (H+) pumps?…

slide25

Electrons Flow Downhill

  • Ele-move in steps from carrier to carrier downhill to oxygen
    • each carrier more electronegative
    • controlled oxidation
    • controlled release of energy
so what s the point

H+

H+

H+

H+

H+

H+

H+

H+

ADP + Pi

H+

So, What’s the point??
  • Set up H+ gradient
  • Allow protonsto flow through ATP synthase
  • Synthesize ATP

ADP + PiATP

CHEMIOSMOSIS!!!

slide27

Energy Conversion

**The Rules: NADH = 3 ATP FADH2 = 2 ATP

  • Glycolysis – 2 NADH
  • Conversion to – 2 NADHAcetyl CoA
  • Krebs cycle - 6 NADH 2 FADH2
  • ETC

6 ATP

6 ATP

18 ATP + 4 ATP = 22 ATP

34 ATP!!!

summing it up

~38 ATP

Summing it up!

+

+

2 ATP

2 ATP

~34 ATP

beyond sugars

proteins    amino acids

H

|

—C—

|

H

hydrolysis

C—OH

N

glycolysis

Krebs cycle

waste

H

O

R

||

Beyond Sugars…

2C sugar =

carbon skeleton =

enters glycolysis or Krebs cycle

amino group =

Waste, excreted as ammonia, urea, or uric acid

slide31

fats    glycerol + fatty acids

hydrolysis

glycerol (3C)  G3P  glycolysis

fatty acids 2C acetyl acetyl Krebs

groups

coA

cycle

2C fatty acids

3C glycerol

enters

glycolysis

as G3P

enter

Krebs cycle

as acetyl CoA

energy from all avenues
Energy from All avenues!
  • Digestion
    • carbohydrates, fats & proteins
      • all catabolized through same pathways
      • enter at different points
    • cell extracts energy from every source
slide33

Why waste? Enough energy? Build stuff!!!

pyruvate glucose

Krebs cycleintermediaries

amino

acids

 

acetyl CoA  fatty acids

  • points in glycolysis & Krebs cycle used as link to pathways for synthesis
    • run pathways “backwards”
      • have extra fuel, build fat!
slide34

What happens the absence of oxygen?

O2

O2

Pyruvate

anaerobicrespirationfermentation

aerobic respirationmitochondria

Krebs cycle

slide35

Alcohol Fermentation

  • Dead end process
    • ~12% ethanol, kills cells
    • can’t reverse reaction
slide36

Lactic Acid Fermentation

  • Reversible process
    • if O2becomes available, lactate converted to pyruvate by the liver
slide38

pyruvate ethanol + CO2

3C

2C

1C

pyruvate lactic acid

NADH

NADH

NAD+

NAD+

3C

3C

Commercial Uses…

  • Bacteria, yeast
  • Animals, some fungi

back to glycolysis

  • beer, wine, bread

back to glycolysis

  • cheese, anaerobic exercise (no O2)
review animations
Review Animations
  • Cell Respiration with Hank
  • ETC
  • ATP Synthase