38813144
Description
Practical 2: Membrane Transport
- Objectives
- To learn and to understand the concept of membrane
transport
- To identify and to observe hypotonic,isotonic and hypertonic
effects to cells
- To learn and to understand the concept of membrane
transport
- Materials and Equipment
- Visking tube, threads, dropper, test
tubes/boiling tubes, test tube rack, test
tube holder, beaker, water bath, 10%
glucose solution, 2% starch suspension,
Iodine solution, Benedict's solution,
distilled water
- Visking tube, threads, dropper, test
tubes/boiling tubes, test tube rack, test
tube holder, beaker, water bath, 10%
glucose solution, 2% starch suspension,
Iodine solution, Benedict's solution,
distilled water
- Introduction
- Membrane transport refers to the collection of mechanisms that regulate the passage of solutes such
as ions and small molecules. The movements of most solutes through the membrane are mediated by
membrane transport proteins. There are categorized as passive transport and active transport. Passive
transport is defined as the molecules move along the concentration gradient and does not require
energy. Active transport is defined as molecules moves against the concentration gradient , requires
energy and involve transport proteins.
- Membrane transport refers to the collection of mechanisms that regulate the passage of solutes such
as ions and small molecules. The movements of most solutes through the membrane are mediated by
membrane transport proteins. There are categorized as passive transport and active transport. Passive
transport is defined as the molecules move along the concentration gradient and does not require
energy. Active transport is defined as molecules moves against the concentration gradient , requires
energy and involve transport proteins.
- Procedure
- Results
- 2% Starch Suspension
- 10% Glucose Solution
- 2% Starch Suspension
- Discussion
- Benedict's Test is used to confirm the presence of glucose. Therefore, the yellow precipitate is formed
after heating the test tube that contains 10% glucose solution. It gives a positive result. The test tube
containing only distilled water remains blue because glucose is not present. Glucose is a large
molecules therefore It is unable to pass through the membrane.
- The results suggest that the visking tube mimics the process of membrane transport by allowing the movement of
small molecules out of the solution. However, it does not allow larger molecules like starch and glucose to pass
through, as indicated by the negative test result for the solution from the beaker.
- Benedict's Test is used to confirm the presence of glucose. Therefore, the yellow precipitate is formed
after heating the test tube that contains 10% glucose solution. It gives a positive result. The test tube
containing only distilled water remains blue because glucose is not present. Glucose is a large
molecules therefore It is unable to pass through the membrane.
- Conclusion
- In conclusion, all objectives have been achieved. Glucose was unable to diffuse through semi-permeable membrane because
it is a large molecule and require transport proteins. As we can see, yellow precipitate was formed after heating because there
were presence of glucose inside the visking tube. Meanwhile, in the beaker which is only contain distilled water shows no
presence of glucose as glucose cannot diffuse through the visking tube directly. In 2% starch suspension, brick red precipitate
was formed after heating because starch is present in the visking tube. Starch cannot diffuse through the visking tube
because it is a large molecules
- In conclusion, all objectives have been achieved. Glucose was unable to diffuse through semi-permeable membrane because
it is a large molecule and require transport proteins. As we can see, yellow precipitate was formed after heating because there
were presence of glucose inside the visking tube. Meanwhile, in the beaker which is only contain distilled water shows no
presence of glucose as glucose cannot diffuse through the visking tube directly. In 2% starch suspension, brick red precipitate
was formed after heating because starch is present in the visking tube. Starch cannot diffuse through the visking tube
because it is a large molecules
Media attachments
0 comments
Want to create your own Mind Maps for free with GoConqr? Learn more.