learning aim B: Explore the effect of activity on respiration in humans and
factors that can affect respiratory pathways
Cellular respiration: It is a metabolic process that occurs in all living organisms. It is a
biochemical process that takes place inside of an organism's cells. In this process, glucose is
broken down to provide energy, which is then used by cells for a variety of functions. All
living organisms performs respiration. There are two types of cellular respiration which are
aerobic and anaerobic respiration. Aerobic respiration requires oxygen and releases lots of
energy. Anaerobic respiration does not require oxygen and releases less energy but more
quickly than aerobic respiration. The chemical equation for aerobic respiration is-
Glucose(C6H12O6) + Oxygen(6O2) → Carbon dioxide (6CO2) + Water (6H2O) + Energy (ATP)
The chemical equation for anaerobic respiration is-
Glucose(C6H12O6) → Alcohol 2(C2H5O H) + Carbon dioxide 2(CO2) + Energy (ATP)
Adenosine triphosphate (ATP)- It is a molecule that carries energy within cells. It is the
main energy currency of the cell. It is a product of the processes of photophosphorylation,
cellular respiration, and fermentation. All living things use ATP. It is made up of the
molecule adenosine and three phosphate groups. It is soluble in water and has a high
energy. ATP is the main energy that is used for all cellular activities. When ATP is hydrolysed
and converted to adenosine diphosphate (ADP), energy is released. All cells reactions are
powered by this energy. Furthermore, ADP can be converted back into ATP so that the
energy is available for other cellular reactions. i
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, A crucial process in cellular metabolism is the conversion of adenosine triphosphate into
adenosine diphosphate and back to ATP. This process is known as the ATP-ADP cycle. Since
it is required for most of cellular processes, ATP is often referred to as the "energy
currency" of the cell. ATP is hydrolysed into ADP and inorganic phosphate, which releases
energy when it is needed for a cellular process. The cell uses this energy to carry out
different metabolic processes. When ATP is depleted, a process known as phosphorylation
converts ADP back to ATP. A phosphate group from the molecule creatine phosphate or the
breakdown of glucose during cellular respiration is transferred during this process. This
cycle of ATP and ADP conversion occurs continuously in cells to maintain the required
energy levels for cellular activities.
Phases of respiration- There are three phases of respiration which are glycolysis, link
reaction, Krebs cycle, and electron transport chain. ii Fermentation is an anaerobic process
that occurs in the absence of oxygen. It is a metabolic pathway that converts glucose into
simpler organic compounds, such as lactic acid or ethanol. Fermentation is an inefficient
process and generates only a small amount of ATP, typically two molecules per molecule of
glucose. Fermentation is used by some organisms, such as certain bacteria and yeast, to
produce energy in the absence of oxygen. But oxidative decarboxylation is an aerobic
process that occurs in the presence of oxygen. It is a metabolic pathway that involves the
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factors that can affect respiratory pathways
Cellular respiration: It is a metabolic process that occurs in all living organisms. It is a
biochemical process that takes place inside of an organism's cells. In this process, glucose is
broken down to provide energy, which is then used by cells for a variety of functions. All
living organisms performs respiration. There are two types of cellular respiration which are
aerobic and anaerobic respiration. Aerobic respiration requires oxygen and releases lots of
energy. Anaerobic respiration does not require oxygen and releases less energy but more
quickly than aerobic respiration. The chemical equation for aerobic respiration is-
Glucose(C6H12O6) + Oxygen(6O2) → Carbon dioxide (6CO2) + Water (6H2O) + Energy (ATP)
The chemical equation for anaerobic respiration is-
Glucose(C6H12O6) → Alcohol 2(C2H5O H) + Carbon dioxide 2(CO2) + Energy (ATP)
Adenosine triphosphate (ATP)- It is a molecule that carries energy within cells. It is the
main energy currency of the cell. It is a product of the processes of photophosphorylation,
cellular respiration, and fermentation. All living things use ATP. It is made up of the
molecule adenosine and three phosphate groups. It is soluble in water and has a high
energy. ATP is the main energy that is used for all cellular activities. When ATP is hydrolysed
and converted to adenosine diphosphate (ADP), energy is released. All cells reactions are
powered by this energy. Furthermore, ADP can be converted back into ATP so that the
energy is available for other cellular reactions. i
1 of 14
, A crucial process in cellular metabolism is the conversion of adenosine triphosphate into
adenosine diphosphate and back to ATP. This process is known as the ATP-ADP cycle. Since
it is required for most of cellular processes, ATP is often referred to as the "energy
currency" of the cell. ATP is hydrolysed into ADP and inorganic phosphate, which releases
energy when it is needed for a cellular process. The cell uses this energy to carry out
different metabolic processes. When ATP is depleted, a process known as phosphorylation
converts ADP back to ATP. A phosphate group from the molecule creatine phosphate or the
breakdown of glucose during cellular respiration is transferred during this process. This
cycle of ATP and ADP conversion occurs continuously in cells to maintain the required
energy levels for cellular activities.
Phases of respiration- There are three phases of respiration which are glycolysis, link
reaction, Krebs cycle, and electron transport chain. ii Fermentation is an anaerobic process
that occurs in the absence of oxygen. It is a metabolic pathway that converts glucose into
simpler organic compounds, such as lactic acid or ethanol. Fermentation is an inefficient
process and generates only a small amount of ATP, typically two molecules per molecule of
glucose. Fermentation is used by some organisms, such as certain bacteria and yeast, to
produce energy in the absence of oxygen. But oxidative decarboxylation is an aerobic
process that occurs in the presence of oxygen. It is a metabolic pathway that involves the
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