Respiration Flashcards
What is respiration?
The release of energy from food
What is usually the food involved in respiration?
The food involved in respiration is usually glucose.
What is internal respiration controlled by and what does it allow?
Internal respiration is controlled by enzymes which allow energy to be released in small amounts
What is energy trapped in?
The energy is trapped in molecules called ATP
What are the two types of respiration?
Aerobic respiration and anaerobic respiration
What is aerobic respiration?
The release of energy from food in the presence of oxygen
What is anaerobic respiration?
The release of energy from food without requiring the presence of oxygen
What do most living things get energy from and what are they called?
Most living things get energy from aerobic respiration and are called aerobes
What is energy stored in in glucose? What happens to it? What is it used for?
The energy stored in bonds in glucose is released and used to make ATP
What happens when ATP breaks down? Why does it do this?
When ATP breaks down it supplies energy for all the reactions in a cell such as movement of muscles, growth of new cells etc.
What is the equation for aerobic respiration?
C6H12O6 + 6O2 -> 6CO2 + 6H2O + Energy
Glucose + Oxygen -> Carbon dioxide + water + energy
Is aerobic respiration efficient?
Aerobic respiration is relatively efficient, 40 percent of the energy in glucose is used to make ATP
What happens to any energy not used to produce ATP?
It is lost as heat
How many stages of aerobic respiration are there? What are they called?
Stage 1 - Glycolysis Stage 2 (no fancy name just stage 2)
Where does stage 1 of aerobic respiration take place?
Takes place in the cytosol (the cytoplasm without the organelles) as enzymes are found here
Does stage 1 of aerobic respiration require oxygen?
Does not require oxygen
Does stage 1 of aerobic respiration release energy?
It only releases small amounts of energy
Does stage 1 of aerobic respiration differ from stage 1 of anaerobic respiration?
Is the same for both aerobic anaerobic respiration
What happens to a 6-carbon carbohydrate in the first stage?
A 6-carbon carbohydrate (Glucose) is converted to two 3-molecules with the release of a small amount of energy
Where does most of the energy in the glucose molecule remain stored?
Most of the energy in the glucose molecule remains stored in each 3-carbon molecule
Does stage two of aerobic respiration need oxygen?
This stage requires and uses oxygen
Does stage two of aerobic respiration release energy?
It releases a large amount of energy
Where does stage two of aerobic respiration occur?
It occurs in the mitochondria as the necessary enzymes are found here
What happens to the 3-carbon molecules in stage two of aerobic respiration?
The 3-carbon molecules are broken down to Carbon Dioxide and Water
What does the complete breakdown of the 3-carbon molecules in stage two of aerobic respiration do?
The complete breakdown of the 3-carbon molecules releases a lot of energy
What is left after stage 2 of aerobic respiration and does it contain a lot of energy?
There is very little energy left in Carbon Dioxide and Water
Is stage 1 of aerobic respiration the same as stage 1 of anaerobic respiration?
yes
Can anaerobic respiration occur without oxygen?
Anaerobic respiration can occur in the presence of oxygen but it does not need to use it.
What occurs in stage 1 of anaerobic respiration?
In anaerobic respiration Glycolysis occurs this means glucose is broken into two 3-carbon molecules
Is energy released in stage 1 of anaerobic respiration?
A small amount of energy is released this way
Is there more than one form of anaerobic respiration?
There are different forms of anaerobic respiration
What is more efficient, anaerobic respiration or aerobic respiration?
Anaerobic respiration is said to be less efficient than aerobic respiration as less energy is released
What happens in the other forms of anaerobic respiration?
where the 3-carbon molecules are converted to different substances but no extra energy is released.
When does lactic acid fermentation occur?
This occurs in some anaerobic bacteria and fungi and in animal muscles when there is not enough oxygen.
What is produced in lactic acid fermentation?
In this fermentation Lactic acid is produced
What is the formula for lactic acid fermentation? In other words what is lactic acid fermentation?
Glucose -> 2Lactic Acid + small amount of energy
Give an example of lactic acid fermentation
e.g. bacteria souring milk and lactic acid in muscles after exercise
Where and when does alcohol fermentation take place?
Take place in bacteria and some fungi such as yeast and in plants when they are deprived of oxygen
What does alcohol fermentation involve?
Involves the partial breakdown of glucose
What is the formula for alcohol fermentation? (basically what is alcohol fermentation?)
Glucose -> 2 Ethanol + 2 Carbon dioxide + small amount energy
Give an example of alcohol fermentation
e.g. alcohol fermentation and bread baking.
What is biotechnology?
Biotechnology refers to the use of living things (such as microorganisms and enzymes) to carry our useful reactions
What happens in industrial fermentation?
In industrial fermentation the microorganisms are placed in a container with a substrate on which they can react
What is the vessel in which biological reactions can take place?
The vessel in which biological reactions can take place is called a Bioreactor
What may be created in industrial fermentation when the microorganisms are mixed with the substrate? What is done to this?
When the microorganisms are mixed with the substrate foam may be formed so a foam breaker is used
What is oxygen pumped into industrial fermentation through?
Oxygen is pumped in through a sparger
What does quality and amount of product depend on in industrial fermentation?
Quality and amount of product depend on the quality of the microorganism and substrate, the design of the bioreactor, a correct rate of mixing, correct temperature and pH and elimination of contaminating microorganisms.
How can it be ensured that the microorganisms used in a bioreactor are not lost at the end of every reaction?
To ensure the microorganisms used in a bioreactor are not lost at the end of every reaction they are often immobilised or fixed.
How can the microorganisms be immobilised for bioprocessing with immobilised cells.?
The microorganisms can be immobilised by bonding them to each other bonding them to an insoluble support or suspending them in a gel or membrane
What is glucose converted to in glycolysis? (detail)
Glucose which is a 6-carbon sugar is converted to two 3-carbon sugars called pyruvic acid
What is pyruvic acid?
This is a neutral molecule which may be found as the negatively charged ion pyruvate
Is oxygen required for glycolysis? What is some of the energy released in it used for?
No oxygen is required some of the energy released forms 2 ATP molecules more of the energy is used to form NADH
How much of the energy is retained in the pyruvic acid?
75 percent of the energy is retained in the pyruvic acid
What happens to pyruvic acid in the presence of oxygen?
In the presence of oxygen the pyruvic acid enters a mitochondrion
What happens to pyruvic acid after in enters a mitochondrion?
It loses a carbon dioxide molecule to form a 2-carbon molecule called Acetyl coenzyme A (Acetyl CoA for short)
What does pyruvic acid lose in the mitochondrion other than carbon dioxide and what does this do?
Pyruvic acid also loses 2 high energy electrons that combine with NAD+ and a proton to form NADH
What happens to each NADH produced in the mitochondrion?
Each NADH will enter an electron transport system
What happens to the Acetyl CoA?
The Acetyl CoA enters a series of reactions called Kreb’s cycle (German scientist Hans Krebs)
Where does the Kreb’s cycle take place?
Takes place in the lumen of the mitochondria
Does the Kreb’s cycle require oxygen?
Yes it requires oxygen
What is the Acetyl CoA broken down into?
The acetyl CoA is broken down into carbon dioxide and protons
What happens to the energy that was in the Acetyl CoA?
The energy that was in the Acetyl CoA is released in a number of steps in the form of high energy electrons
What happens to the high energy electrons in which form the energy is released from Acetyl CoA?
These electrons along with protons (H+) combine with NAD+ to form NADH
What happens to the NADH formed in the Kreb’s cycle?
The NADH enters an electron transport system
What other process occurs in the Kreb’s cycle other than the breakdown of Acetyl CoA and what does it involve?
Phosphorylation also occurs in Kreb’s cycle where a single ADP is changed to ATP
What happens to NADH?
The NADH enters an electron transport chain
Where does electron transport chain take place?
Takes place in the cristae of the mitochondria
Is oxygen necessary for the electron transport chain?
Oxygen is necessary
What do the foldings of the cristae do?
The foldings of the cristae increase the number of electron transport systems that can fit in them
What happens to the energy produced in the electron transport system?
Some of this energy is used to form ATP the rest is lost as heat.
What happens at the end of each system and how?
At the end of each system the low energy electron is removed by combining it with oxygen and hydrogen to form water.
What is the production of ATP called and why?
The production of ATP by the electron transport system is called Oxidative Phosphorylation as it requires oxygen + phosphate
What is the main significance of the electron transport system?
The main significance of the electron transport system is that it produces energy rich ATP.
Is oxygen essential for the electron transport system?
Oxygen is essential as it accepts the low energy electron at the end of the chain.
What happens if oxygen is absent in the electron transport system?
If oxygen is absent aerobic organisms may die as there is no oxygen to accept the low energy electron and no ATP may be formed.
What may chemicals such as cyanide do? Why?
Chemicals such as cyanide may be fatal because they prevent some of the proteins from receiving and passing on electrons meaning ATP cannot be produced.
What happens to glucose stage one of anaerobic respiration?
In stage 1 glucose is converted to 2 molecules of pyruvic acid
What is produced in stage one of anaerobic respiration when glucose is converted to 2 molecules of pyruvic acid?
2 molecules of ATP and 2 molecules of NADH are produced in this process
What happens to pyruvic acid in the absence of oxygen?
In the absence of oxygen the pyruvic acid is converted to either lactic acid or ethanol and carbon dioxide
What happens when in the absence of oxygen the pyruvic acid is converted to either lactic acid or ethanol and carbon dioxide?
In each case the 2 NADH break down into 2 electrons and 2 protons which combine with the pyruvic acid to form lactic acid or ethanol and carbon dioxide.
What can you say about pyruvic acid as it gains electrons?
As pyruvic acid gains electrons in both cases it is said to be reduced
As only stage 1 is involved in anaerobic respiration, where does it occur?
As only stage 1 is involved in anaerobic respiration it only occurs in the cytosol.
