This experiment was conducted to investigate the selective permeability of dialysis tubing. The permeability of the tubing to glucose, starch, and iodine (potassium iodide) was tested. The dialysis tubing was clipped to form a bag so that glucose and starch were fed into the bag through the other end, and was also clipped to avoid the seeping of the solution.
More selectively controls what goes in and out of cell.
Is not rigid.
Explanation:
The question entails the structural and functional differences of the cell wall and cell membrane.
The cell wall is a rigid and strong layer that covers the outside of plant cells. It is absent in animal cells.
The cell wall is largely composed of cellulose, hemicellulose and pectin in plants and peptidoglycan in bacteria. The cell membrane, on the other hand, is comprised of a lipid bilayer.
The strong and complex network of cellulose renders the cell wall rigid; whereas, as it is made up of lipid bilayer, the cell membrane is flexible and elastic.
Unlike the cell membrane, which allows the movement of selective substances, the cell wall does not allow any substances to pass through.
both the number of species and population density decreases as altitude above sea level increases
question 2:
increase in birth rate => greater number of young organisms
Explanation:
As altitude above sea level increases, O2 density decreases, the amount of UV rays increases and the difference between daytime and nighttime temperature increases
