2. Review on Cytoplasm
• It’s a jelly-like fluid that fills a cell.
• It is made up of mostly water and salt.
• It contains molecules such as enzymes.
• It is made of 70% - 90% water and is
colorless usually.
The inner of the
cytoplasm is known as
the endoplasm
3. What exactly is the cytoplasm
• It is basically everything within the cell excluding
the nucleus.
• inside cell – nucleus = cytoplasm
• The cytoplasm is made up of three components.
They are;
Membrane enclosed organelle
Cytosol
Inclusions
4. Membrane enclosed organelles
• These are distributed throughout the cell
cytoplasm.
• They are each specialized to perform a different
function.
• organelles are suspended in the cytoplasm.
5.
6. Cytosol
• This is the gel-like substance that is enclosed
within the cell membrane that is not held by the
organelles inside the cell.
• it is a complex mixture of cytoskeleton filaments,
dissolved molecules and water.
• It is the site of many chemical reactions that are
fundamental to the cells existence.
7. Cytosol, the complex mixture
• Cytoskeleton filament
This is what give the cell its shape.
It is made up of the protein filament (actin
filament) and microtubules.
• Water
70% of the Cytosol is made of water.
8. Cytosol, the complex mixture
• Dissolved molecules
This is small and large molecules and dissolved
ions.
Enzymes, fatty acids, sugars, nucleic acids, &
amino acids are used to keep the cell working.
Waste products are present until removed.
9. Inclusions
• These are stored nutrients, crystals, secretary
products and pigment granules.
• They are the accumulation of material that is not
metabolically active.
• They are usually present in the Cytosol only
temporarily.
• They are non-soluble molecules
11. Function of the cytoplasm
• It aids in movement of genetic material and
products of cellular respiration within the cell.
• It helps to fill out the cell and keep organelles in
their place.
• It gives the cell its shape.
• It aids to dissolve waste products.
12. Function of the cytoplasm
• It prevents the grouping of organelles in places
due to gravity that would prevent their function.
• It acts as a buffer and protects the genetics
material of the cell from damage caused due to
movement and collision with other cells.
• It aids in metabolic activity.
13. Question time
• Which of the following is a types of inclusion?
A. Glycogen inclusions
B. Lipids inclusions
C. Crystalline inclusions
D. Lipofusion inclusions
14.
15. Metabolic activity in the cytoplasm -
Glycolysis
• This is the 1st stage in cellular respiration
which occurs for energy production.
• It can occur both during aerobic and anaerobic
respiration.
• The glycolytic enzymes needed are all found
in the Cytosol.
16.
17. Glycolysis
• Therefore, 2 ATP, 2 NADH, 2 H+ and 2 pyruvic
acid molecules are formed at the end of
this reaction.
• Steps 1 and 3 = – 2ATP
Steps 7 and 10 = + 4 ATP
therefore;
• Net visible ATP produced = 2.
18. Question time
• In what step is enzyme Aldolase used to split
fructose 1, 6-bisphosphate into two sugars,
which are isomers of each other?
the fourth step.
Hinweis der Redaktion
cytosol is confined by the boundaries of a matrix which fills the part of the cell that does not contain organelles.
The first step in glycolysis is the changing of glucose into glucose-6-phosphate by adding a phosphate group. The hexokinase enzyme catalyzes this reaction.
The second step of the reaction of glycolysis occurs as a rearrangement of glucose 6-phosphate into fructose 6-phosphate by glucose phosphate isomerase (Phosphoglucose Isomerase).
In the third step of the reaction, Phosphofructokinase, with magnesium as a cofactor, changes fructose 6-phosphate into fructose 1,6-bisphosphate.
In the fourth step, enzyme Aldolase is used to split fructose 1, 6-bisphosphate into two sugars, which are isomers of each other. These two sugars are dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phosphate (GAP).
In the fifth step, GAP is the only molecule that continues in the glycolytic pathway therefore the enzyme triophosphate isomerase, reorganizes the DHAP into GAP so it can continue in glycolysis.
In the sixth step, Glyceraldehyde-3-phosphate dehydrogenase dehydrogenates and an inorganic phosphate is added to glyceraldehyde 3-phosphate, to produce 1,3-bisphosphoglycerate. The enzyme yields 1,3 bisphoglycerate, NADH, and a hydrogen atom.
In the seventh step, the enzyme Phosphoglycerate kinase transfers a phosphate group from 1,3-bisphosphoglycerate to ADP to form ATP and 3-phosphoglycerate as magnesium as a cofactor.
In the eight step, The enzyme phosphoglycero mutase relocates the Phosphate group from 3- phosphoglycerate from the 3rd carbon to the 2nd carbon to form 2-phosphoglycerate.
In the ninth step, The enzyme enolase removes a molecule of water from 2-phosphoglycerate to form phosphoenolpyruvic acid .
In the tenth step, The enzyme pyruvate kinase transfers a Phosphate group from phosphoenolpyruvate (PEP) to ADP to form pyruvic acid and ATP. Since there are two molecules of PEP, 2 ATP molecules are actually generated.