Adenosine triphosphate (ATP) is an RNA nucleotide with an adenine base. Adenine + ribose = adenosine with two additional phosphate groups attached to its phosphate group.

The phosphate-to-phosphate bonds are unique and despite being weak their bonds are rich in energy. Cells store energy in this way in the form of chemical bond energy.

The primary structure of a protein would in turn influence the secondary structure of a protein or in some cases can cause a protein to become denatured. Even if one amino acid is missing or if two amino acids were to exchange positions in the polypeptide chain this could alter the how the protein functions. Examples of this can be seen in certain types of mutations.

This is the regular structure of polypeptide chains into a regular repeating pattern , held together by hydrogen bonds The secondary structure of the protein contributes towards the shape of the protein and hence the function of the protein.

Enzymes tend to have a globular Tertiary structure, this structure lays a critical role in the function of a protein and is held together by hydrogen, ionic and covalent bonding. This structure is easy to disrupt despite the number of bonds that hold this structure together. Most of these bonds are hydrogen bonds, in addition the other bonds are considered to be weak and can be influenced by environmental changes such as pH and temperature. The bonds assist in the folding of the peptide, to hold it in a 3d-shape.

In some cases, proteins with tertiary structures associate together through weak attractive forces and function as a single unit. More specifically the interactions between different polypeptide chains such as hydrogen bonding, ionic interactions and covalent bonding.

During glycolysis which is the splitting of the glucose molecule into two molecules of pyruvate, four molecules of ATP are formed but two molecules of ATP are consumed.

Overall two molecules of ATP are produced in this process.
This process involves 3 enzymes hexokinase , phosphofructokinase and pyruvate kinase.

In animals during anaerobic respiration lactic acid is produced.

In animal, the enzyme LAD (lactic acid dehydrogenase) converts excess pyruvate into lactic acid by the addition of hydrogen. Lactic acid is a 3 C acid and when oxygen becomes available LAD removes the hydrogen converting it to pyruvate.

The pyruvic acid is converted into acetate by the enzyme PAD (pyruvic acid dehydrogenase). The acetate is assisted into the mitochondria by the action of coenzyme A.

The electron transport chain also occurs within the mitochondria. In this process, electrons are passed from one molecule to another.

Oxygen is at the end of this chain where it accepts electrons and pick up protons to form water.

This chain involves a series of multienzyme complexes. Some of the enzymes involved include ATP synthase complex and NADH dehydrogenase complex.

The reactions of photosynthesis takes place in thylakoids. A collection of Thylakoids is called a Granum

These are a type of specialized plastids that exist in plant cells . This type of plastid produces and stores a molecule known asa chlorophyll. Plastids produce and store other pigment molecules such as carotenes.

Many enzymatic reactions participate in the longer metabolic pathways where the product of one step becomes the next substrate for the next step. Different enzymes are required to catalyze each step.

Some of the types of enzymes involved in the metabolic process include:

Possess an electron carrier system located on the membranes of the organelle.

ATP is produced on these membranes through the process of chemiosmosis.

ATP and NADPH is produced in the light-dependent stage is consumed in the light-independent stage.

These organelles of this system all participate in the synthesis, modification and transportation of proteins and lipids.

After examining the various organelles involved in the endomembrane system, create a mind map and write down the organelles in the endomembrane system and state what roles they play within this system.

Cell membranes exist as two layers of phospholipids.; each phospholipid has a hydrophilic, water-soluble end and a hydrophobic, non-water-soluble end. One of the water-soluble end faces the outer environment and the other water-soluble end faces the cytoplasm.

Glycoproteins and other proteins are embedded in the phospholipid bilayer; they impart a unique identity to the cell. Some proteins act as doors opening and closing the paths through the cell membranes and some proteins are involved in transport.

Liposomes are artificial lipid vesicles that can be used to improve delivery of materials to cells.

This is the movement of materials across the cell membrane without the use of energy from the cell.

Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration. Molecular collisions are responsible for diffusion and it is not confined to gases but can occur with liquids as well. Oxygen and carbon dioxide move across the cell membrane by diffusion.

Osmosis is the diffusion of water molecules across a selectively permeable membrane. Osmosis is just the diffusion of water and will follow the concentration gradient which is the difference in the number of molecules or ions of a substance between adjoining regions. Without energy substances tend to diffuse from an area of higher concentrations to areas of lower concentration until equilibrium is achieved.

Equilibrium a condition in which acting influences are balanced, resulting in a stable environment.

The movement of water in and out of cells is important to life processes and cells are immersed in isotonic solutions – which are solutions in which the concentration of the solution outside the cell is equal to the concentration of the solution inside the cell.

One of the blood’s major function is to maintain an isotonic balance which is part of homeostasis. Homeostasis is the process in which a constant internal environment is maintained in spite of various changes in the internal and external environment..

Facilitated Diffusion uses proteins or carry polar molecules or ions across the cell membrane