Phospholipids Lab Report
Phospholipids are made up from many smaller molecules combine these are: fatty acid chains, glycerol, phosphate and choline. Two of the carbons of the glycerol are joined to two fatty acids in a condensation reaction creating ester bonds. The final carbon is bonded to the phosphate molecule, which in turn is connected via a covalent bond to choline. Due to the polar nature of the glycerol phosphate and choline molecules, they create a hydrophilic area (known as the hydrophilic head). Whereas, the fatty acids are non-polar and therefore form a hydrophobic area (known as the hydrophobic tails). This means that phospholipids are amphipathic, as they have both a hydrophobic and hydrophilic sections.
http://www.fastbleep.com/biology-notes/31/170/969 …show more content…
As the phospholipids are amphipathic when they exist in an aqueous environment, the molecules try and arrange themselves in a manner that will leave the hydrophilic sections in connection with water but the hydrophobic section not in contact with water.
As the phospholipids are not able to do this on their own they combine to create the optimal situation. Four main solutions for this are micelles, liposomes, monolayer and bilayer sheet. Micelles uses the least amount of phospholipids as it forms a small single layer spherical ball with the hydrophobic tails surrounded by the hydrophilic head keeping the water out. Liposomes are similar to micelles but yet are larger and duel layered (bilayer) as well as the outer layer it has another inner layer of phospholipids from another aqueous environment that the liposome has formed round. The Monolayers can only be formed at the surface on the water this is as it is the only area that the phospholipids can avoid the water without creating a different environment. Hydrophobic tails stick upward out of the water at the surface and the hydrophilic heads remain in the water. Finally, the bilayer sheets form across the environment, for example if placed in a breaker of water it is possible that the phospholipids form a bilayer from each side of the breaker (creating 2 new …show more content…
environments).
Creating different environments is a key importance in the functioning and specialization of cells. It was not only one of the first structures to be made in the primordial soup, it is also used by every form of life. As stated my plopper.G 2013, ‘for a cell to remain alive, it must never be in chemical equilibrium with its surrounding environment’. Without the phospholipid bilayer, the equilibrium would be formed meaning gradients would not be able to be formed. The bilayer also keeps organelles inside the cell together so molecules produced within the cell can be directly transported to other organelles that need the molecule. Without this membrane keeping the organelles together they would not form mutual relationships as the organelles would not be held close enough together for a long enough time.
Like phospholipids proteins can be polar, leading to having hydrophobic and hydrophilic sections. This is due to the differing -R groups on the amino acids possibly having polar regions as well as non-polar regions. Interactions like this give the bilayer the ability to have proteins within itself. The proteins like the phospholipids both have to find either optimal positions, this means that the protiens hydrophobic sections will want to be embedded into the membrane. These proteins associated with the membrane can exist in three forms integrated proteins, peripheral proteins and lipid bound/anchored proteins. Integrated proteins usually span the width of the bilayer, an example of this is the human erythrocyte glycophorin. Lipid anchored proteins have a section of the protein embedded in the membrane to anchor them in the membrane, for example cytochrome b5. Peripheral proteins are not affected as much but the hydrophilic and hydrophobic interactions, this is due to how it binds (using hydrogen bonds) to the other three types of proteins within the membrane or the phospholipid heads. An example of this is cytochrome c which associated with the inner mitochondrial membrane (yeagle.p, 1987)
Membrane embedded proteins have many various roles, from cell signalling to transport of materials across the membrane.
There are five major types of integrated proteins these are: transporter, enzyme, cell surface receptor, identity markers and cell adhesion. Each of these types are greatly important in the functioning of cells in eukaryote organisms. Intercellular communication is needed for a eukaryotic organism to survive as it needs to be able to interact with the external environment. Cells would not produce needed products for the body to use to manage the internal environment as they cannot receive any signals from the receptor cells, without cell surface receptors and identity markers cells the chemical signals would not be able to be
read.
Cell adhesion
Transporter proteins are extremely varied, acting as one of the largest factors responsible for facilitated diffusion of substances across the membrane. To create concentration gradients, active transport is needed to transport the molecules against the gradient. This is highly useful in mitochondria, cytochrome c oxidase (complex IV) of located in the inner membrane of the membrane and moves hydrogen ions across the membrane. The diffusion gradient is key in the production of Adenosine Triphosphate, as without the diffusion gradient there would not be a proton motive force to activate the ATP synthase. http://www.bio.davidson.edu/Courses/Molbio/MolStudents/spring2003/Bennett/protein1.htm ATP synthase is a common Integral enzyme protein, which is to be found embedded within the membrane of the inner mitochondria. Utilizing the concentration gradient to facilitate the addition of phosphate to adenosine diphosphate creating adenosine triphosphate creating energy from the organism.
Proteins in the membrane are many and very varied as the human genome codes for 6,000 to 7,500 different membrane proteins. Just for the process of oxidative phosphorylation, integrated transport and enzyme proteins are needed along with the peripheral proteins such as cytochrome c. this provides the mitochondria to be able to be synthesise ATP, mean without membrane proteins the organism is unable to perform active processes. Along with this if around only around 5 membrane proteins are necessary for this process, it would seem that many of the membrane proteins assist other significant processes within organisms as there are 6,000+ are coded for.
http://www.fastbleep.com/biology-notes/31/170/969 …show more content…
As the phospholipids are amphipathic when they exist in an aqueous environment, the molecules try and arrange themselves in a manner that will leave the hydrophilic sections in connection with water but the hydrophobic section not in contact with water.
As the phospholipids are not able to do this on their own they combine to create the optimal situation. Four main solutions for this are micelles, liposomes, monolayer and bilayer sheet. Micelles uses the least amount of phospholipids as it forms a small single layer spherical ball with the hydrophobic tails surrounded by the hydrophilic head keeping the water out. Liposomes are similar to micelles but yet are larger and duel layered (bilayer) as well as the outer layer it has another inner layer of phospholipids from another aqueous environment that the liposome has formed round. The Monolayers can only be formed at the surface on the water this is as it is the only area that the phospholipids can avoid the water without creating a different environment. Hydrophobic tails stick upward out of the water at the surface and the hydrophilic heads remain in the water. Finally, the bilayer sheets form across the environment, for example if placed in a breaker of water it is possible that the phospholipids form a bilayer from each side of the breaker (creating 2 new …show more content…
environments).
Creating different environments is a key importance in the functioning and specialization of cells. It was not only one of the first structures to be made in the primordial soup, it is also used by every form of life. As stated my plopper.G 2013, ‘for a cell to remain alive, it must never be in chemical equilibrium with its surrounding environment’. Without the phospholipid bilayer, the equilibrium would be formed meaning gradients would not be able to be formed. The bilayer also keeps organelles inside the cell together so molecules produced within the cell can be directly transported to other organelles that need the molecule. Without this membrane keeping the organelles together they would not form mutual relationships as the organelles would not be held close enough together for a long enough time.
Like phospholipids proteins can be polar, leading to having hydrophobic and hydrophilic sections. This is due to the differing -R groups on the amino acids possibly having polar regions as well as non-polar regions. Interactions like this give the bilayer the ability to have proteins within itself. The proteins like the phospholipids both have to find either optimal positions, this means that the protiens hydrophobic sections will want to be embedded into the membrane. These proteins associated with the membrane can exist in three forms integrated proteins, peripheral proteins and lipid bound/anchored proteins. Integrated proteins usually span the width of the bilayer, an example of this is the human erythrocyte glycophorin. Lipid anchored proteins have a section of the protein embedded in the membrane to anchor them in the membrane, for example cytochrome b5. Peripheral proteins are not affected as much but the hydrophilic and hydrophobic interactions, this is due to how it binds (using hydrogen bonds) to the other three types of proteins within the membrane or the phospholipid heads. An example of this is cytochrome c which associated with the inner mitochondrial membrane (yeagle.p, 1987)
Membrane embedded proteins have many various roles, from cell signalling to transport of materials across the membrane.
There are five major types of integrated proteins these are: transporter, enzyme, cell surface receptor, identity markers and cell adhesion. Each of these types are greatly important in the functioning of cells in eukaryote organisms. Intercellular communication is needed for a eukaryotic organism to survive as it needs to be able to interact with the external environment. Cells would not produce needed products for the body to use to manage the internal environment as they cannot receive any signals from the receptor cells, without cell surface receptors and identity markers cells the chemical signals would not be able to be
read.
Cell adhesion
Transporter proteins are extremely varied, acting as one of the largest factors responsible for facilitated diffusion of substances across the membrane. To create concentration gradients, active transport is needed to transport the molecules against the gradient. This is highly useful in mitochondria, cytochrome c oxidase (complex IV) of located in the inner membrane of the membrane and moves hydrogen ions across the membrane. The diffusion gradient is key in the production of Adenosine Triphosphate, as without the diffusion gradient there would not be a proton motive force to activate the ATP synthase. http://www.bio.davidson.edu/Courses/Molbio/MolStudents/spring2003/Bennett/protein1.htm ATP synthase is a common Integral enzyme protein, which is to be found embedded within the membrane of the inner mitochondria. Utilizing the concentration gradient to facilitate the addition of phosphate to adenosine diphosphate creating adenosine triphosphate creating energy from the organism.
Proteins in the membrane are many and very varied as the human genome codes for 6,000 to 7,500 different membrane proteins. Just for the process of oxidative phosphorylation, integrated transport and enzyme proteins are needed along with the peripheral proteins such as cytochrome c. this provides the mitochondria to be able to be synthesise ATP, mean without membrane proteins the organism is unable to perform active processes. Along with this if around only around 5 membrane proteins are necessary for this process, it would seem that many of the membrane proteins assist other significant processes within organisms as there are 6,000+ are coded for.