Cellular Respiration

Cellular Respiration and Breathing

Aerobic process – requires oxygen.

Cellular Respiration – exchange of oxygen and carbon dioxide between a cell and its environment

Breathing – exchange of oxygen and carbon dioxide between your blood and the outside air.

Cellular Respiration

Purpose: Generate ATP for cellular work

38 ATPs made per glucose molecule

Electron Transport Chain

During Respiration glucose is broken down in several steps.

Molecules (electron carriers)

accept electrons from glucose and pass them to other carriers (electron transport chain).

In each transfer the electrons release a little energy, which is trapped to make ATP.

Electron Transport Chain (cont’d)

Oxygen is the final electron acceptor.

It takes the electrons and joins them with hydrogen ions to form water.

Cellular Respiration

Structure of Mitochondria

Double membrane envelope with space in between.

Inner membrane is highly folded and encloses a fluid filled space called the Matrix.

Complex folding allows for sites where reactions can occur to make ATP.

Mitochondria

Article

What type of process is glycolysis?

A. aerobic B. anaerobic

Your muscles use the most energy...

A. At rest B. During aerobic activity C. During anaerobic acitivity

A by-product of cellular respiration is:

A. Oxygen B. Carbon Dioxide C. Glucose

Stage 1: Glycolysis

Breaking down a glucose molecule Takes place in the cytoplasm

Stage 1: Glycolysis

Input: 2 ATP molecules, Glucose

Output: 4 ATP molecules, 2 pyruvic acid molecules & 2 NADH molecules

Stage 2: The Krebs Cycle

Finishes the breakdown of pyruvic acid to carbon dioxide, releasing more energy.

Takes place in matrix of the inner membrane of mitochondria.

Stage 2: The Krebs Cycle

Input: 2 Pyruvic Acids (from 1 glucose) Output: 2 ATP molecules, 4 carbon dioxide

molecules.

What is the final net gain of ATP molecules in the first stage, glycolysis?

A. 4 B. 6 C. 2 D. 1

How many ATP molecules were made in the second stage, the Krebs cycle for one glucose molecule?

A. 1 B. 2 C. 3 D. 4

Stage 3: Electron Transport Chain and ATP Synthase Action Occurs in the inner membrane of the

mitochondria. 2 Part Process

Part 1

NADH transfers electrons from glucose to transports chain.

Electrons move down the transport chain, releasing energy which is used to pump hydrogen atoms across the membrane from an area of low to high concentration.

Part 2

Hydrogen atoms flow back through ATP synthases (protein structures in mitochondria) to the outside of the mitochondria.

ATP synthase uses the energy from the hydrogen flow to convert ADP to ATP. (34 ATPs/glucose molecule)

How many ATP molecules were made in the third stage, the electron transport chain?

A. 4 B. 2 C. 34 D. 38

From Kreb’s

From Glycolysis

From Acetyl Formation

FADH2

NADH

Electrons Flowing (e-)

H2O (made)

(2 electrons needed)

O2 (consumed)

H+ (pumped in)

ATP (produced)

DO NOW: COPY THIS CHART!!!!

Notes

For every 1 electron moving across a pump, one H+ ion is pumped in.

For every NADH, 6 H+ ions are pumped into the mitochondria.

For every FADH, 4 H+ ions are pumped in

Notes

Total H+ = (# of electrons flowing) X (# of pumps)

For every 2 H+ ions moving through ATP synthase, 1 ATP is formed.

COPY THISSUMMARY For every 1 electron moving across a pump, one H+

ion is pumped in.

Each NADH and FADH2 holds 2 electrons.

Total H+ = (# of electrons flowing) X (# of pumps)

For every 2 H+ ions moving through ATP synthase, 1 ATP is formed.

If 3 NADH’s flow across 3 pumps how many H+ ions enter the mitochondria?

How many ATPs are formed?