Cellular Respiration

What is cellular respiration

The breakdown of organic molecules to produce energy.

What are the reactants in cellular respiration

Organic molecules and oxygen

What are the products of photosynthesis

Organic molecules and Oxygen

What sort of metabolic pathways release stored energy by breaking down complex molecules

Catabolic pathways

What is aerobic respiration

Consumtion of organic molecules and O2 and to produce ATP

What is anaerobic respiration

Consumption of organic molecules to produce ATP without using O2

What is fermentation

The partial degradation of sugars that occurs without O2

What is the equation for cellular respiration

C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy (ATP + heat)

What is oxidation

When a substance loses electrons

What is reduction

When a substance gains electrons, or is reduced (the amount of positive charge is reduced)

What is an electron donor called

A reducing agent

What is an electron acceptor called

An oxidizing agent

When electrons are pulled away from a less electronegative atom to a more electronegative atom what is released

Energy

Which atom is more electronegative Hydrogen or Oxygen

Oxygen

What happens to the electrons of a hydrogen atom when combined with oxygen

They are pulled closer to the oxygen

What happens when oxygen atoms pull electrons away (oxidized) from hydrogen atoms

Energy is released

What type of molecules make good fuels

Molecules with lots of carbon and hydrogen atoms like hydrocarbons and glucose

Why do hydrocarbons and glucose make good fuels

When combined with oxygen the many hydrogen atoms can be oxidized to release energy

How do cells deal with energy

In small doses not in large quantities at one time

What is broken down in cellular respiration

Glucose

What is NAD+

An electron acceptor functioning as an oxidizing agent during cellular respiration

What is NAD reduced to

NADH

What is the function of NADH

It stores energy trapped in the electrons to the electron transport chain

What is the function of the electron transport chain

To release the energy stored in the NADH electrons in a series of steps instead of one explosive reaction

What happens to the energy yielded by the electron transport chain

The energy yielded is used to regenerate ATP

What are the 3 stages of cellular respiration

Glycoyisis

Citric acid (Krebs) cycle

Oxidative phosphorylation

What is the function of glycolysis

To break glucose down into two molecules of pyruvate

What is the function of the citric acid cycle

To complete the break down of glucose

What is the function of oxidative phosphorylation

ATP synthesis

Which of the 3 stages of cellular respiration produces the most ATP

Oxidative phosphorylation

Where does glyolysis occur

The cytoplasm

There does the citric acid cycle occur

Mitochondrial matrix

Where does oxidative phosphorylation occur

Inner mitochondrial membrane

How many molecules of ATP are produced by complete oxidation of 1 molecule of glucose

32

Is glycoyisis aerobic or anaerobic

Anaerobic, it does not need oxygen

How many molecules of ATP does glycolysis in total and how many ATP molecules does it use to produce those. What is the net production of ATP

It produces 4 molecules of ATP and uses 2. The net production is therefore 2 molecules of ATP

What is the final product of glycolysis

Two molecules of pyruvate

What happens to the pyruvate

It is converted to Acetyl CoA

What enzyme converts pyruvate to Acetyl CoA

Pyruvate dehydrogenase

The citric acid cycle starts with acetyl CoA combining with oxaloacetate to form what

Citrate

The citric acid cycle comprises of seven steps decomposing the citrate to what

oxaloacetate

The citric acid cycle reduces 2 electron carriers what are they

NADH

FADH2

What is the function of NADH and FADH2

These two electron carriers donate electrons to the electron transport chain, which powers ATP synthesis via oxidative phosphorylation

Where is the electron transport chain found

Inner mitochondial membrane

How many proteins in the electron transport chain

4

How does the electronegativity of the proteins in the electron transport chain differ.

They areeach a bit more electronegative than the previous one

How does the electronegativity of the proteins in the electron transport chain compare to oxygen

They are all less electronegative than oxygen.

Electrons from NADH and FADH2 are passed to the electron transport chain and pulled down the chain when a more electronegative atom pulls electrons away from a less electronegative one. What happens every time an electron is pulled from one atom to another

Energy is released

What is the final acceptor of electrons

Oxygen

What is the energy released by the electron transport chain used for

Pumping hydrogen ions (protons) out of the mitochondria

Where do the hydrogen ions (protons) pumped out of the mitochondria go

Into the space between the mitochondrial membranes

What does pumping the hydrogen ions (protons) out of the mitochondria cause

A hydrogen ion(proton) gradient with a greater concentration outside than in

Where do the hydrogen ions (protons) diffuse back into the mitochondria down its concentration gradient

Through the protein complex, ATP synthase

What does ATP synthase do

It uses the energy in exergonic flow of H+ to produce ATP from ADP

What happens to the hydrogen ions

What is chemiosmosis

The use of energy in a H+ gradient to drive cellular work

What is the H+ gradient across the mitochondrial membrane referred to

Proton-motive force, emphasizing its capacity to do work

What happens to the hydrogen ions once they have diffused back into the mitochondria

They combine with oxygen to form water

Without O2, the electron transport chain will cease to operate. In such conditions from where does the body obtain ATP

From glycolysis

What has to be regenerated to allow glycolysis to produce ATP in anaerobic conditions

NAD+

What is fermentation

Glycolysis plus reactions that regenerate NAD+, which can be reused by glycolysis

What are two types of fermentation

Alcohol fermentation

Lactic acid fermentation

Which produces more ATP a gram of fat or a gram of carbohydrate

Fat

Which enzyme regulates the rate of cell respiration

Phosphofructokinase

What is known to inhibit Phosphofructokinase

ATP

Citrate

What is known to activate Phosphofructokinase

ADP and AMP