Biology

Your lab group is experimenting with the diffusion of molecules across a membrane. Dialysis tubing is used as a model cell membrane because is it semi-permeable, allowing small molecules to cross the membrane, but NOT larger molecules, like starch. A starch solution is placed in the dialysis tubing and then the dialysis tubing is placed in an iodine and water solution. Iodine is used as an indicator for the presence of starch. Normally, iodine is a yellow-brown color (on the left), but in the presence of starch, it turns a deep purple (right). After observing the experimental setup for 20 minutes, the iodine solution remains brown, but the starch solution inside the dialysis tubing is purple and swollen. What CANNOT be concluded from the results?

A] Iodine is a small molecule and diffused through the dialysis tubing INTO the starch solution.
B) Starch is a large molecule and could NOT diffuse through the dialysis tubing into the iodine solution.
C) Starch requires ATP energy for transport and therefore cannot cross the dialysis tubing into the iodine solution.
D) The starch solution is hypertonic to the iodine solution, causing water to move across the dialysis tubing INTO the starch solution.

  1. 👍
  2. 👎
  3. 👁
  1. it was C

    1. 👍
    2. 👎

Respond to this Question

First Name

Your Response

Similar Questions

  1. biology

    During diffusion, when the concentration of molecules on both sides of a membrane is the same, the molecules will a. move across the membrane to the outside of the cell b. stop moving across the membrane*** c. continue to move

  2. chemistry

    1. Which of the following statements about the cell theory is correct? a) All living organisms are made up of one or more cells. b) All cells arise from other, pre-existing cells c) All eukaryotic cells contain symbiotic

  3. bio

    The cell membrane is a highly selective barrier that controls the movement of substances in and out of the cell. In fact, polar molecules are unable to go across unless A. they are enclosed in water-filled vesicles. B. they pass

  4. AP Biology

    Cells transport substances across their membrane. Choose THREE of the following four types of cellular transport Osmosis Active transport Facilitated diffusion Endo/exocytosis For each of the three transport types you choose, a.

  1. Science Ms.Sue

    Which phase in mitosis or meiosis are these 1.Chromosomes pair up and can exchange genetic material 2.The nuclear membrane in the daughter cells breaks down 3.The chromosomes line up along the center of the cell and two spindle

  2. chemistry

    Some liquids have enough attractions between molecules to form dimers. (Dimers are molecules formed from the combination of identical molecules, A + A --> A2.) What effect would this have on the experimental molar mass? This was a

  3. biology

    1. Toward what condition does diffusion eventually lead, in the absence of other influences? 2. How is osmosis related to diffusion? 3. If the concentration of solute molecules outside a cell is lower than the concentration in the

  4. science

    Which term refers to the diffusion of water through a membrane? A. osmosis B. engulfing C. active transport D. facilitated transport

  1. Living environment

    Defective receptor proteins on a cell membrane have the least effect on 1.homeostasis 2.Muscle activity 3. nerve signals 4. Diffusion

  2. Microbiology

    Which of the following statements about the outer membrane of Gram-negative cell wall is FALSE? A. The outside leaflet is largely composed of lipopolysaccharides. B. The outer membrane contains porins that allow passage of

  3. ap bio

    16 .Action potentials are generated along a neuron because __________. A.of cytoplasmic streaming within the neuron B.depolarization of the membrane at one point causes an increase of permeability to sodium at the next point

  4. chemistry

    elements x and y are from group 7 in the periodic table. x is a liquid at rtp, while y is a solid at rtp. which statements are correct? 1) atoms of y have more protons than atoms of x 2) molecules of y have more atoms than

You can view more similar questions or ask a new question.