Cell Transport Mechanisms and Permeability

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Lab 1: Cell Transport Mechanisms and Permeability
Purpose
The purpose of this experiment is to have a better understanding of the subject matter and to understand the difference between active and passive cellular transport. It will also help to define diffusion and describe the process that occurs when certain solutes come in contact and are either stopped or move through the plasma membrane.

Hypothesis
I believe the plasma membrane is selective about what is able to and not able to pass through it. It stops undesirable substances from passing and it will take in nutrients that are acceptable or needed. Materials & Methods

Materials:
Online Pearson's Lab.

Methods:
Follow the steps and procedures laid out for me.
Results
Experiment Results

Predict Question:
Predict Question 1: The molecular weight of urea is 60.07. Do you think urea will diffuse through the 20 MWCO membrane? Your answer : a. Yes, but very slowly.
Predict Question 2: Recall that glucose is a monosaccharide, albumin is a protein with 607 amino acids, and the average molecular weight of a single amino acid is 135 g/mole.
Which of the following will be able to diffuse through the 200 MWCO membrane? Your answer : c. glucose only
Stop & Think Questions:
The reason sodium chloride didn't diffuse left to right is that You correctly answered: c. the membrane pore size was too small. Glucose is a six-carbon sugar. Albumin is a protein with 607 amino acids. The average molecular weight of a single amino acid is 135 g/mole. There is no reason to run these solutes at the 20 MWCO because You correctly answered: d. glucose and albumin are both too large to pass. The rate of diffusion for urea

You correctly answered: b. is slower than that for sodium because urea is a larger molecule.

Experiment Data:

Solute MWCO Solute Concentration Average Diffusion Rate
Na+ Cl- 20 9.00 0.0000
Urea 20 9.00 0.0000
Na+ Cl- 50 9.00 0.0150
Na+ Cl- 50 18.00 0.0300
Na+ Cl- 100 9.00 0.0150
Urea 100 9.00 0.0094
Glucose 200 9.00 0.0040
Albumin 200 9.00 0.0000
Experiment Results

Predict Question:
Predict Question 1: What effect do you think increasing the number of protein carriers will have on the glucose transport rate?
Your answer : b. The glucose transport rate will increase.
Predict Question 2: What effect do you think adding Na+ Cl- will have on the glucose transport rate? Your answer : a. The glucose transport rate will increase.
Stop & Think Questions:
What happened to the glucose transport rate when the glucose concentration was increased from 2 mM to 8 mM?
You correctly answered: a. The glucose transport rate increased. Describe the conditions that resulted in the fastest rate of glucose transport. You correctly answered: d. 700 glucose carrier proteins and 8 mM glucose Why do you think equilibrium wasn't reached?

You correctly answered: b. The membrane proteins were saturated.

Experiment Data:

Run Number Solute Start Conc. L Start Conc. R Carriers Rate
1 Glucose 2.00 0.00 500 0.0008
2 Glucose 8.00 0.00 500 0.0023
3 Glucose 2.00 0.00 700 0.0010
4 Glucose 8.00 0.00 700 0.0031
5 Glucose 10.00 0.00 100 0.0017#
6 Na+ Cl- 0.00 2.00 700 0.0042
6 Glucose 2.00 0.00 700 0.0010
Experiment Results

Predict Question:
Predict Question 1: What effect do you think increasing the Na+ Cl- concentration will have? Your answer : a. increased pressure
Predict Question 2: What do you think will be the pressure result of the current experimental conditions? Your answer : b. pressure above the right beaker
Stop & Think Questions:
Why do you think there is no pressure change?
You correctly answered: b. Sodium is able to diffuse through the pores. Why do you think there was no pressure change?
You correctly answered: c. There is no net movement of water because the solute concentrations are the same.

Experiment Data:

Run Number Solute MWCO Start Conc. L Pres. L Start Conc. R Pres. R Rate 1 Na+ Cl- 20 5.00 170...
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