G1: Apply knowledge of organic molecules.
Phospholipids: are a class of lipids that are a major component of all cell membranes. They can form lipid bilayers because of their characteristics.
Proteins: are large, complex molecules that play many roles in the body. They do most of the work in cells and are required for the structure, function, and regulation of the body's tissues and organs.
Glyoproteins: are proteins that contain oligosaccharide chains (glycans) attached to polypeptide side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification
Glycolipids: are lipids with a carbohydrate attached by a glycosidic bond. Their role is to serve as markers for cellular recognition and also to provide energy.
Carbohydrates: are one of the main types of nutrients. They are the most important source of energy for your body. Your digestive system changes carbohydrates into glucose (blood sugar).
G2: Identify the hydrophobic and hydrophobic regions of the phosphoric bilayer.
Phospholipids are the primary molecules found in the plasma membrane. A phospholipid is unique in that it has a hydrophilic region called the head, and a hydrophobic region known as the tail. The hydrophilic region can interact with water due to the presence of a phosphate group which is polar, like water. If something is hydrophilic, that means it likes water.
Phospholipids: are a class of lipids that are a major component of all cell membranes. They can form lipid bilayers because of their characteristics.
Proteins: are large, complex molecules that play many roles in the body. They do most of the work in cells and are required for the structure, function, and regulation of the body's tissues and organs.
Glyoproteins: are proteins that contain oligosaccharide chains (glycans) attached to polypeptide side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification
Glycolipids: are lipids with a carbohydrate attached by a glycosidic bond. Their role is to serve as markers for cellular recognition and also to provide energy.
Carbohydrates: are one of the main types of nutrients. They are the most important source of energy for your body. Your digestive system changes carbohydrates into glucose (blood sugar).
G2: Identify the hydrophobic and hydrophobic regions of the phosphoric bilayer.
Phospholipids are the primary molecules found in the plasma membrane. A phospholipid is unique in that it has a hydrophilic region called the head, and a hydrophobic region known as the tail. The hydrophilic region can interact with water due to the presence of a phosphate group which is polar, like water. If something is hydrophilic, that means it likes water.
G3: Describe passive transport processes including osmosis and diffusion.
Passive transport is a movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy input.
Osmosis is the spontaneous net movement of solvent molecules through a semi-permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides.
Diffusion refers to the process by which molecules intermingle as a result of their kinetic energy of random motion.
Passive transport is a movement of biochemicals and other atomic or molecular substances across cell membranes without need of energy input.
Osmosis is the spontaneous net movement of solvent molecules through a semi-permeable membrane into a region of higher solute concentration, in the direction that tends to equalize the solute concentrations on the two sides.
Diffusion refers to the process by which molecules intermingle as a result of their kinetic energy of random motion.
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G5: Compare and Contrast the following:
Diffusion is the movement of molecule from a place of high concentration to a place of low concentration through a semi-permeable membrane.
Osmosis is the movement of molecules from a place of high water concentration to a place of low water concentration through a semi-permeable membrane.
Thus the only difference is that Osmosis is to do with water.
G6: Explain why the cell membrane is described as "selectively permeable"
A selectively permeable cell membrane is one that allows certain molecules or ions to pass through it by means of active or passive transport. Active transport processes require the cell to expend energy to move the materials, while passive transport can be done without using cellular energy.
G7: Explain factors that affect the rate of diffusion across a cell membrane.
-Temperature: at higher temperatures, more collisions will occur. Thus, more molecules will pass successfully into and out of the plasma membrane; the rate of diffusion increases.
-Concentration: if there is a high concentration gradient, the rate of diffusion is faster, as more molecules quickly try to reach dynamic equilibrium.
-Agitation: if agitation occurs, the non covalent interactions of the peripheral proteins are disturbed. Also, the plasma membrane structure is disturbed in such a way as to allow more molecules to pass through it.
G8: Predict the effects of hypertonic, isotonic, and hypotonic
Hypertonic solutions have more solute than the inside of the cell. As a result of diffusion, the cell loses water to the solution (net movement). This results in the cell shrinking. This process is called plasmolysis: the contraction of the cell contents due to the loss of water or the shrinking of cytoplasm due to osmosis.
Hypotonic solutions have less solute than the inside of the cell. The net movement of water is therefore into the cell as a result of osmosis. In animal cells, cells tend to expand and sometimes burst due to the buildup of turgor pressure.
Isotonic there are no effects on the cell.
G9: Devise an experiment using the scientific method
The scientific method is a plan that is followed in performing a scientific experiment and writing up the results.
G11: Explain why cells divide when they reach a particular surface area to volume ratio.
Surface area increases as the square of the size increase, whereas the volume increases as the cube of the size increase. For example, doubling the dimensions of a cell would make its surface area 4 times as big, but its volume 8 times as big.
The effect of this is that the surface area-to-volume RATIO decreases rather quickly as the cell gets bigger. Put another way, the volume of the cell increases much quicker than the surface area does.
Diffusion is the movement of molecule from a place of high concentration to a place of low concentration through a semi-permeable membrane.
Osmosis is the movement of molecules from a place of high water concentration to a place of low water concentration through a semi-permeable membrane.
Thus the only difference is that Osmosis is to do with water.
G6: Explain why the cell membrane is described as "selectively permeable"
A selectively permeable cell membrane is one that allows certain molecules or ions to pass through it by means of active or passive transport. Active transport processes require the cell to expend energy to move the materials, while passive transport can be done without using cellular energy.
G7: Explain factors that affect the rate of diffusion across a cell membrane.
-Temperature: at higher temperatures, more collisions will occur. Thus, more molecules will pass successfully into and out of the plasma membrane; the rate of diffusion increases.
-Concentration: if there is a high concentration gradient, the rate of diffusion is faster, as more molecules quickly try to reach dynamic equilibrium.
-Agitation: if agitation occurs, the non covalent interactions of the peripheral proteins are disturbed. Also, the plasma membrane structure is disturbed in such a way as to allow more molecules to pass through it.
G8: Predict the effects of hypertonic, isotonic, and hypotonic
Hypertonic solutions have more solute than the inside of the cell. As a result of diffusion, the cell loses water to the solution (net movement). This results in the cell shrinking. This process is called plasmolysis: the contraction of the cell contents due to the loss of water or the shrinking of cytoplasm due to osmosis.
Hypotonic solutions have less solute than the inside of the cell. The net movement of water is therefore into the cell as a result of osmosis. In animal cells, cells tend to expand and sometimes burst due to the buildup of turgor pressure.
Isotonic there are no effects on the cell.
G9: Devise an experiment using the scientific method
The scientific method is a plan that is followed in performing a scientific experiment and writing up the results.
G11: Explain why cells divide when they reach a particular surface area to volume ratio.
Surface area increases as the square of the size increase, whereas the volume increases as the cube of the size increase. For example, doubling the dimensions of a cell would make its surface area 4 times as big, but its volume 8 times as big.
The effect of this is that the surface area-to-volume RATIO decreases rather quickly as the cell gets bigger. Put another way, the volume of the cell increases much quicker than the surface area does.