Glycogen is a carbon-containing substance that is important in the storage of
glucose in animals. It contains Carbon Hydrogen and Oxygen and is a polymer of
alpha glucose. It forms 1,4 and 1,6 glycosidic bonds. The 1,6 bonds are important
because this causes the branches. The branched structure of glycogen is important
because it allows glycogen to have a large surface area for enzymes to attach and
for the hydrolysis of glucose, using a molecule of water, to occur so it can be used in
metabolic processes such as respiration. There is a lot of glycogen in the liver and
muscle cells. Glycogen is an important carbon-containing molecule because it allows
glucose to be stored without affecting the water potentials of cells. This is because
glycogen is insoluble so will not have any osmotic effect. Its rapid hydrolysis means
that lots of ATP can be made from respiration and energy from ATP can be used for
things like active transport to absorb glucose from the ileum epithelium into the
bloodstream. Cellulose is another carbon-containing substance that is important in
the structure of the cell wall in plants. It is a polymer of beta glucose that forms 1,4
glycosidic bonds which make straight chains, these chains are then linked together
by many hydrogen bonds to form strong fibres called myofibrils. These fibres provide
strength to the cell wall and the whole plant so it can grow upward towards the light
for the light-dependent reaction in photosynthesis.
Glucose is a carbon-containing compound with the formula (C6H12O6) it is an
important molecule in organisms as it allows cells to produce ATP in the process of
respiration. Glucose can be used as a respiratory substrate in both aerobic and
anaerobic respiration. However, glucose isn’t the only respiratory substrate that can
be used in aerobic respiration. Some products resulting from the breakdown of other
molecules, such as fatty acids from lipids and amino acids form protein, all
carbon-containing substances, that can be converted into molecules to are able to
enter the Krebs cycle. In glycolysis, glucose is phosphorylated using a phosphate
from a molecule of ATP. This is then converted from glycerate-3phosphate to triose
phosphate, which is oxidised, forming two molecules of pyruvate. The pyruvate Is
decarboxylated, removing a carbon atom, the pyruvate is oxidised to form acetate
which is combined with coenzyme A to form acetyl coenzyme A. Acetyl coenzyme A
is used in the Krebs cycle to produce reduced coenzymes (NAD/FAD) and ATP.
Without the carbon-containing substance, glucose, the processes of glycolysis, the
link reaction, the Krebs cycle or oxidative phosphorylation would not be possible so
less ATP would be produced at respiring muscle cells so ATP cannot be used to
cause myosin head to bend which pulls the actin filament along as well as it not
being able to be used to break the actin-myosin cross bridge for muscle contraction.