Study Guide ANSWER KEY Ch 3
Name: Emily Roth
Chapter 3 Check and Challenge Date: November 22, 2014 Hr: 5th hour
Check and Challenge p 80
1.) What materials need to be exchanged across a cell membrane?
Water, nutrients, waste, gasses (O2/CO2), amino acids (to build proteins), sugars (carbos), lipids, nucleic acids.
2.) In what way is an organism a protected compartment?
Organisms have many layers of cells and material (such as skin) that protect them from the environment. The also arare selectively permeable in determining what they eat.
3.) What is the significance of a membranes being selectively permeable?
It allows the cells to control its internal environment.
Check and Challenge p 85
1. What is a concentration gradient? How does it affect diffusion?
Concentration gradient is a difference in the concentration of molecules across a membrane or a distance. Diffision is a basic process that allows molecules to movr into and out of the cell, which is possible with the concentration gradient.
2. Explain the differences between active and passive transport. Why is each important to the cell?
Going from low to high concentration would require cellular energy to move the material (Active Transport). Going from high to low concentration requires no cellular energy (Passive Transport) and is favorable to the cell.
3.) In what way is a cell membrane selectively permeable?
The selectively permeable cell membrane allows the cell to regulates the exchange of materials in/out of the cell. Controls the internal environment of the cell.
4.) Would you expect osmosis and diffusion to stop when substances are evenly distributed? Support your answer.
If there is no concentration gradient (when the substances are evenly distributed) there will be NO osmosis or diffusion. There will be movement across the membrane, because the molecules are always moving. This movement will be in equlibrium.
5.) What type of evidence demonstrates active transport?
Active transport requires
Chapter 3 Check and Challenge Date: November 22, 2014 Hr: 5th hour
Check and Challenge p 80
1.) What materials need to be exchanged across a cell membrane?
Water, nutrients, waste, gasses (O2/CO2), amino acids (to build proteins), sugars (carbos), lipids, nucleic acids.
2.) In what way is an organism a protected compartment?
Organisms have many layers of cells and material (such as skin) that protect them from the environment. The also arare selectively permeable in determining what they eat.
3.) What is the significance of a membranes being selectively permeable?
It allows the cells to control its internal environment.
Check and Challenge p 85
1. What is a concentration gradient? How does it affect diffusion?
Concentration gradient is a difference in the concentration of molecules across a membrane or a distance. Diffision is a basic process that allows molecules to movr into and out of the cell, which is possible with the concentration gradient.
2. Explain the differences between active and passive transport. Why is each important to the cell?
Going from low to high concentration would require cellular energy to move the material (Active Transport). Going from high to low concentration requires no cellular energy (Passive Transport) and is favorable to the cell.
3.) In what way is a cell membrane selectively permeable?
The selectively permeable cell membrane allows the cell to regulates the exchange of materials in/out of the cell. Controls the internal environment of the cell.
4.) Would you expect osmosis and diffusion to stop when substances are evenly distributed? Support your answer.
If there is no concentration gradient (when the substances are evenly distributed) there will be NO osmosis or diffusion. There will be movement across the membrane, because the molecules are always moving. This movement will be in equlibrium.
5.) What type of evidence demonstrates active transport?
Active transport requires