Respiration
An intermediate product formed during the aerobic respiration of a
molecule of glucose. Pyruvic acid loses one molecule of carbon
dioxide and two hydrogen atoms to form this compound. It then
enters Kreb’s cycle and reacts with citric acid to form oxaloacetic
acid.
acetyl co-enzyme
A
Compound containing nitrogen. It is one of the purine nucleotide
bases of DNA and RNA, also is a part of the ATP molecule.
adenine
It is formed by the release of energy in a cell from ATP. It is
converted back into ATP by the addition of a phosphate group
during respiration.
A compound composed of a molecule of adenine, one of ribose and
three phosphate groups. The bonds between the phosphate groups
are high-energy bonds. When these bonds are broken, energy is
released. It is the source of energy in a cell – it traps and transfers
energy for cell activities. Formed in the mitochondria of a cell during
respiration or photosynthesis.
ADP (adenosine
diphosphate)
ATP (adenosine
triphosphate)
Bacteria that can only live with or in the presence of free oxygen
from the air. They require oxygen for respiration.
aerobic (bacteria)
The controlled release of energy from food within a cell using
oxygen. The process is controlled by enzymes and is very efficient.
aerobic
respiration
It is one of the end products of anaerobic respiration (fermentation),
the other being carbon dioxide.
alcohol (ethyl
alcohol or ethanol)
The enzyme-controlled release of energy from food in a cell in the
absence of oxygen. It is an inefficient process. Oxygen may be
present but will not be used
The controlled release of energy from food, within the cell/cells of
an organism. It is a twenty-four hour process controlled by enzymes.
It can occur with (aerobic) or without (anaerobic) the use of oxygen.
Also called internal, tissue or cellular ...
The second stage in respiration involving a complex series of
enzyme-controlled reactions where pyruvic acid, in the presence of
oxygen, is broken down to carbon dioxide, water and ATP. This takes
place in the lumen of the mitochondria.
During photosynthesis and aerobic respiration, a high energy
electron is transferred along a series of chemicals (carriers). At each
transfer, sufficient energy is lost from the electron to convert ADP
into ATP.
Chemical reactions that liberate energy, e.g. respiration.
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anaerobic
respiration
respiration
Kreb's cycle (citric
acid cycle)
electron transport
system
exergonic
A chemical reaction where heat energy is released from the
reactants to the surroundings, e.g. respiration.
exothermic
Organism that respires with or without oxygen, depending on its
availability.
facultative
anaerobe
The physical process of taking in oxygen (inhalation or inspiration)
and giving out of carbon dioxide and water vapour to the air
(exhalation or expiration).
breathing
(external
respiration)
Production of alcohol from starch and sugars contained in grain or
fruit. This was probably the first use of biotechnology by humans.
fermentation
The first stage of respiration that involves the conversion of glucose
(6-carbon compound) to pyruvic acid (3-carbon compound) in the
cytoplasm with the release of energy. Energy is also required to start
this process.
glycolysis
Substances that transport hydrogen in biological reactions by
reduction and oxidation, e.g. NADP in photosynthesis.
hydrogen
carrier(s)
A by-product of anaerobic respiration in animal cells. Can be
converted back into pyruvic acid and then oxidised in the usual way
if oxygen is present, or it may be sent to the liver where, in the
presence of oxygen, it is converted to glycogen or glucose. Causes
cramps in muscles.
lactic acid
NAD (nicotinamide
An oxidising and reducing co-enzyme used in respiration. It traps and
adenine
transfers electrons for cell activities.
dinucleotide)
Compel or bind to a certain environment or conditions.
obligate
Organisms that only survive in the presence of oxygen.
obligate aerobe
Organisms that only survive in absence of oxygen, e.g. some
bacteria.
obligate
anaerobes
A chemical reaction in which oxygen combines with another
substance.
OR A reaction which involves the removal of hydrogen from a
compound.
OR A reaction that involves the loss of electrons.
A 3-carbon compound formed in glycolysis. In anaerobic conditions
it is converted to ethanol and carbon dioxide (in yeast), or it is
converted to lactic acid in animal muscle (causes cramp). Under
aerobic conditions it goes into Kreb's Cycle and is completely broken
down to carbon dioxide and water – a lot of energy is released
during this process.
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oxidation
pyruvic acid
(pyruvate)
The speed at which energy is released/used OR the speed at which
oxygen is used OR the speed at which carbon dioxide is produced.
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rate of respiration