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Cellular Cellular RespirationRespiration

How do living things get energy?

Living things get the ENERGY they need from the breakdown of glucose (sugar)

ATP=Energy

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Question:n: In what kinds organisms does

cellular respiration take place?

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Cellular respiration take place in Plants and Animals Plants – Autotrophs: self-producers. Animals - Heterotrophs: consumers.

All organisms need a source of energy. Heterotrophs use the organic compounds in food for

energy sources. Before energy in complex carbohydrates can be used

by cells, it must be broken down into simple sugars like glucose.

This breakdown of glucose is done by our digestive system.

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Mitochondria OrganelleOrganelle where cellularcellular respirationrespiration

takes place.

Innermembrane

Outermembrane

Innermembrane space

MatrixCristae

Cellular Respiration

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Cellular Respiration

The process that releases energy (ATP) by breaking down food molecules in the presence of oxygen.

Requires food molecules ex: Glucose (sugar) and Oxygen. Gives off carbon dioxide, water, and Energy.

C6H12O6 + 6O2 6CO2 + 6H2O + energy

glucoseglucose ATP

Summary All our cells need energy ATP is the energy that the cells use

for all life processes. The cell makes ATP by breaking

down a sugar called glucose. Glucose is the energy of the body. ATP is the energy of the cell

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Steps in cellular respiration

Step one: is always Glycolysis. Glyco = sugar : lysis= breaking/ split

Glycolysis is splitting glucose Step two: depends on whether

oxygen is present or not.

Step One Glycolysis Glycolysis is the process in which one

molecule of glucose (6 Carbons) is broken “in half”, producing two molecules of pyruvic acid, a 3-carbon compound.

Occurs in CYTOPLASM of cell. Video Clip

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Glycolysis

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2 ATP needed to begin glycolysis. 4 ATP produced when its done. NET gain 2 ATP. (4 – 2 = 2) NADH is an electron carrier. Glycolysis starts w/ ONE GLUCOSE Ends with TWO PYRUVIC ACID Video clip

Step Two

Oxygen Present or not?

(No) If oxygen is not present (anaerobic) Step two is Fermentation

(Yes) If Oxygen is PRESENT (aerobic) step two is the Krebs Cycle & Electron Transport Chain

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Glucose

Glycolysis Krebs cycle

Electrontransport

Fermentation (without oxygen)

Alcohol or lactic

acid

Chemical Pathways

Oxygen is not present.Fermentation:

Two types of fermentation1. Alcoholic Fermentation

Used by Yeast and a few other microorganisms.

Produces alcohol and carbon dioxide from the three carbon pyruvic acid.

2. Lactic Acid Fermentation Used by Bacteria and human muscle

cells. Produces lactic acid from the three

carbon pyruvic acid.

Oxygen is present Krebs Cycle- Step 2

Occurs in mitochondria (matrix) 2 molecules of ATP is generated per

glucose. CO2 is produced and released.

Electron Transport Chain- Step 3 Takes place in mitochondria (inner

membrane). 32 molecules of ATP are produced per

glucose molecule.

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Krebs Cycle (Step 2 oxygen) When oxygen is present such as in muscles, step two

in cellular respiration is the Krebs Cycle Occurs in mitochondria Pyruvic acid is changed in a series of reactions. These reactions produce high-energy electron

carriers to be used in the electron transport chain NAD+ and FAD+ are the high energy electron carriers H+ is the electron that needs to be carried. They turn into NADH and FADH2 when carrying

electrons and provide the energy to drive the Electron Transport Chain.

2 molecules of ATP is generated per glucose. CO2 is produced and released.

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Electron Transport Chain (Step 3 Oxygen)

Takes place in mitochondria (inner membrane).

Series of proteins accept high energy electron pairs from NADH and FADH2. NADH and FADH2 (Energy taxi dropping off

energy) Oxygen bonds with 2 hydrogens (final

electron acceptor) to form H20 32 molecules of ATP are produced per

glucose molecule.

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TOTAL ATP YIELD

1. 02 ATP –Glycolysis2. 02 ATP Krebs3. 32 ATP - ETC 36 ATP - TOTAL Net

ATPATP

Glycolysis

Krebs Cycle

Electron Transport

NADH and FADH2

In Cytoplasm

In Mitochondria with oxygen present

2 ATP

2 ATP 32 ATP

Cytoplasm

Pyruvicacid

Mitochondrion

Electrons carried in NADH

Electrons carried in NADH and FADH2

Glucose Glycolysis

2 2 32

ADP ATP

Energy Released

Video Clip

Summary Step one is always glycolysis. Step two depends on whether or not

oxygen is present. If it is not, then step two is

fermentation, (anaerobic respiration) If it is, then step two is the Krebs Cycle

and step 3 is the electron transport chain.

In the process, organic glucose is converted to inorganic CO2

If oxygen is present, its called Aerobic respiration, and 36 ATP are created.

During anaerobic respiration or fermentation, 2 ATP are created.

ATP is the universal energy molecule, meaning that all living organism use it as an energy source.

Notice that much more ATP is made when oxygen is present.

How does glucose get into the body? Through the foods you eat. You eat a piece of bread, which is made of large carbohydrate

molecules. Your body breaks the large carbs into tiny sugars during digestion. It starts with the saliva in the mouth, then in the stomach and finally

as the food passes through intestines. When the carbs reach the large intestines, they are broken down so

small that they get absorbed in the blood. The small sugars are monosaccharides

Glucose is one of these monosaccharides. The red blood cells then carry the small sugars to the cells that need

them.

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Identify the cellular process that most likely produced the CO2 in the body cellExplain why carbon dioxide moves into red blood cells by diffusion rather than active transport.