1. The chapter Evolution in Action box discusses how viruses infect specific organs.
How do viruses use cellular membranes to attack specific organs?
Specific glycoprotein molecules exposed on the surface of the cell membranes of host
cells are exploited by many viruses to infect specific organs. For example, HIV is able to
penetrate the plasma membranes of specific kinds of white blood cells called T-helper
cells and monocytes, as well as some cells of the central nervous system.
2. What is meant by the terms “fluid mosaic” and “selective permeability” when
describing membranes?
Fluid Mosaic is the model used to describe the structure and function of a plasma
membrane and its. structure-diverse protein molecules. Selective permeability is the
property of biological membranes that allows them to regulate the passage of
substances across them.
3. Use the words diffusion and concentration gradient in a sentence.
A diffuser uses diffusion to spread molecules within the scents or oils into the air.The
concentration gradient guarantees that the cell is within equilibrium and evenly
distributes substances such as dye.
4. How does the structure of the membrane relate to its selective permeability? (Think
about the chemical properties of the inner core of the bi-layer.)
The membrane forms a barrier between the inside of the cell and the outside. The
structure only allows necessary molecules to enter and exit.
5. What kinds of molecules can freely cross through passive transport without transport
proteins? (Review and define the words polar and nonpolar if you need to!)
Non Polar
6. What kinds of molecules use facilitated diffusion (a kind of passive transport that
requires transporter proteins)?
Polar molecules and Ions are the molecules that facilitate diffusion.
How do viruses use cellular membranes to attack specific organs?
Specific glycoprotein molecules exposed on the surface of the cell membranes of host
cells are exploited by many viruses to infect specific organs. For example, HIV is able to
penetrate the plasma membranes of specific kinds of white blood cells called T-helper
cells and monocytes, as well as some cells of the central nervous system.
2. What is meant by the terms “fluid mosaic” and “selective permeability” when
describing membranes?
Fluid Mosaic is the model used to describe the structure and function of a plasma
membrane and its. structure-diverse protein molecules. Selective permeability is the
property of biological membranes that allows them to regulate the passage of
substances across them.
3. Use the words diffusion and concentration gradient in a sentence.
A diffuser uses diffusion to spread molecules within the scents or oils into the air.The
concentration gradient guarantees that the cell is within equilibrium and evenly
distributes substances such as dye.
4. How does the structure of the membrane relate to its selective permeability? (Think
about the chemical properties of the inner core of the bi-layer.)
The membrane forms a barrier between the inside of the cell and the outside. The
structure only allows necessary molecules to enter and exit.
5. What kinds of molecules can freely cross through passive transport without transport
proteins? (Review and define the words polar and nonpolar if you need to!)
Non Polar
6. What kinds of molecules use facilitated diffusion (a kind of passive transport that
requires transporter proteins)?
Polar molecules and Ions are the molecules that facilitate diffusion.
