lab 3 a&p 1

Caroline Phillips
Lab 3: The Cell

Purpose

During this lab I hope to acquire a complete understanding of the makeup of the cell and all of its functions.

Hypothesis

If I complete this lab, then I will have a full understanding of the topics covered in the chapter “The Cell” and will have a complete understanding of the makeup of the cell and all of its functions.

Materials & Methods

Materials: “Human Anatomy & Physiology ninth edition” Elaine N. Marieb; Katja Hoehn

Methods:
1. Read entire file twice
2. Read each set of directions
3. Complete each activity

Data/Analysis:

Activity 1:
Review Sheet Results
1. Describe two variables that affect the rate of diffusion.
Your answer:
Increasing the number of membrane carriers and the concentration.
2. Why do you think the urea was not able to diffuse through the 20 MWCO membrane? How well did the results compare with your prediction?
Your answer:
Because Urea was too big to pass through the 20 MWCO membrane
3. Describe the results of the attempts to diffuse glucose and albumin through the 200 MWCO membrane. How well did the results compare with your prediction?
Your answer:
glucose diffused through the 200 MWCO membrane, while there was no diffusion of albumin. I predicted correctly.
4. Put the following in order from smallest to largest molecular weight: glucose, sodium chloride, albumin, and urea. Your answer:
sodium chloride, urea, glucose, albumin.
Experiment Data:
Solute
MWCO
Left Solute Concentration
Right Solute Concentration
Average Diffusion Rate
Na+ Cl-
20
9.00
0.00
0.0000
Urea
20
0.00
0.00
0.0000
Albumin
20
0.00
0.00
0.0000
Glucose
20
0.00
0.00
0.0000
Na+ Cl-
20
0.00
0.00
0.0000
Urea
20
9.00
0.00
0.0000
Albumin
20
0.00
0.00
0.0000
Glucose
20
0.00
0.00
0.0000
Na+ Cl-
20
0.00
0.00
0.0000
Urea
20
9.00
0.00
0.0000
Albumin
20
0.00
0.00
0.0000
Glucose
20
0.00
0.00
0.0000
Na+ Cl-
50
9.00
0.00
0.0150
Urea
50
0.00
0.00
0.0000
Albumin
50
0.00
0.00
0.0000
Glucose
50
0.00
0.00
0.0000
Na+ Cl-
50
18.00
0.00
0.0273
Urea
50
0.00
0.00
0.0000
Albumin
50
0.00
0.00
0.0000
Glucose
50
0.00
0.00
0.0000
Na+ Cl-
100
9.00
0.00
0.0150
Urea
100
0.00
0.00
0.0000
09/12/14 page 2
Solute
MWCO
Left Solute Concentration
Right Solute Concentration
Average Diffusion Rate
Albumin
100
0.00
0.00
0.0000
Glucose
100
0.00
0.00
0.0000
Na+ Cl-
100
0.00
0.00
0.0000
Urea
100
9.00
0.00
0.0094
Albumin
100
0.00
0.00
0.0000
Glucose
100
0.00
0.00
0.0000
Na+ Cl-
200
0.00
0.00
0.0000
Urea
200
0.00
0.00
0.0000
Albumin
200
0.00
0.00
0.0000
Glucose
200
9.00
0.00
0.0042
Na+ Cl-
200
0.00
0.00
0.0000
Urea
200
0.00
0.00
0.0000
Albumin
200
9.00
0.00
0.0000
Glucose
200
0.00
0.00
0.0000

Activity 2:
Review Sheet Results
1. Explain one way in which facilitated diffusion is the same as simple diffusion and one way in which it is different from simple diffusion.
Your answer:
one way in which they are the same is that they both transport molecules along or down the concentration gradient of the solute and they do not require energy from an outside source. One way they differ is that facilitated diffusion requires a membrane bound carrier protein to aid in the transportation of a molecule across the membrane. Simple diffusion occurs without assistance of membrane proteins.
2. The larger value obtained when more glucose carriers were present corresponds to an increase in the rate of glucose transport. Explain why the rate increased. How well did the results compare with your prediction?
Your answer:
The rate of glucose transportation increased when more glucose carriers were present becasue more glucose molecules could bind to the glucose carries present. This resulted in an increased number of glucose molecules to cross the membrane. The results from the experiment proved this because as the number of glucose carriers increased the rate of glucose transportation also increased.
3. Explain your prediction for the effect Na+ Cl- might have on glucose transport. In other words, explain why you picked the choice that you did. How well did the results compare with your prediction?
Your answer:
I chose that there would be no change in the glucose transport rate because Na+Cl- is transported using simple diffusion which does not require a carrier protein, so Na+Cl- is independent from the glusoce transport. Adding the NaCl has no effect on the rate of the glucose transport. The results from the experiment proved this.
Experiment Data:
Run Number
Solute
Start Conc. L
Start Conc. R
Carriers
Rate
1
Na+ Cl-
0.00
0.00
500
0.0000
1
Glucose
2.00
0.00
500
0.0008
2
Na+ Cl-
0.00
0.00
500
0.0000
2
Glucose
8.00
0.00
500
0.0023
3
Na+ Cl-
0.00
0.00
700
0.0000
3
Glucose
2.00
0.00
700
0.0010
4
Na+ Cl-
0.00
0.00
700
0.0000
4
Glucose
8.00
0.00
700
0.0031
5
Na+ Cl-
0.00
0.00
100
0.0000
5
Glucose
10.00
0.00
100
0.0028#
6
Na+ Cl-
0.00
2.00
700
0.0042
6
Glucose
2.00
0.00
700
0.0010

Activity 3:
Review Sheet Results
1. Explain the effect that increasing the Na+ Cl- concentration had on osmotic pressure and why it has this effect. How well did the results compare with your prediction?
Your answer:
Increasing the concentrtion of Nacl molecules at a constant MWCO will result in an increased osmotic pressure. The high concentration of molecules in one side of the membrane creates an increased force of water movement to the higher concentrated side of the membrane. Increasing the number of nondissoluble molecules increases osmotic pressure. If the molecules are able to diffuse through the membrane then equilibrium will be reachedand no pressure generated. The resulst from the experiment supported this.
2. Describe one way in which osmosis is similar to simple diffusion and one way in which it is different.
Your answer:
One way in which it is similar to simple diffusion os both processes are passive, menaing the molecules diffuse from an area of high to low concentration without the use of energy from the external source. One way in which it is different from simple diffusion is that during simple diffusion ions and molecules are transported across the membrane. In osmosis only solvents are transported through a selectively permiable membrane.
3. Solutes are sometimes measured in milliosmoles. Explain the statement, “Water chases milliosmoles.”
Your answer:
The statement means that as solute concentration increases, the concentration of water decreases. Osmosis occurs whenever there is a difference of water concentrations between two sides of a membrane. The water diffuses to the side of the membrane which contains the highest concentration of solutes.
4. The conditions were 9 mM albumin in the left beaker and 10 mM glucose in the right beaker with the 200 MWCO membrane in place. Explain the results. How well did the results compare with your prediction?
Your answer:
The 10 mM glucose molecules were able to diffuse from the right to left beaker until equilibrium was acheived.The 9 mM albumin was not able to diffuse through the 200 MWCO and remained in the left beaker. This resulted in the osmotic pressure of 153 mmHG. The results from the experiment supported my predictions.
Experiment Data:
Run Number
Solute
MWCO
Start Conc. L
Pres. L
Start Conc. R
Pres. R
Rate
1
Na+ Cl-
20
5.00
170
0.00
0
0.0000
1
Albumin
20
0.00
170
0.00
0
0.0000
1
Glucose
20
0.00
170
0.00
0
0.0000
2
Na+ Cl-
20
10.00
340
0.00
0
0.0000
2
Albumin
20
0.00
340
0.00
0
0.0000
2
Glucose
20
0.00
340
0.00
0
0.0000
3
Na+ Cl-
50
10.00
0
0.00
0
0.0167
3
Albumin
50
0.00
0
0.00
0
0.0000
3
Glucose
50
0.00
0
0.00
0
0.0000
4
Na+ Cl-
100
0.00
136
0.00
0
0.0000
4
Albumin
100
0.00
136
0.00
0
0.0000
4
Glucose
100
8.00
136
0.00
0
0.0000
5
Na+ Cl-
100
0.00
0
0.00
0
0.0000
5
Albumin
100
0.00
0
0.00
0
0.0000
5
Glucose
100
8.00
0
8.00
0
0.0000
6
Na+ Cl-
200
0.00
0
0.00
0
0.0000
6
Albumin
200
0.00
0
0.00
0
0.0000
6
Glucose
200
8.00
0
0.00
0
0.0036
7
Na+ Cl-
200
0.00
153
0.00
0
0.0000
7
Albumin
200
9.00
153
0.00
0
0.0000
7
Glucose
200
0.00
153
10.00
0
0.0044

Activity 4:
Review Sheet Results
1. Explain in your own words why increasing the pore size increased the filtration rate. Use an analogy to support your statement. How well did the results compare with your prediction?
Your answer:
When you increase the pore size the filtration rate also increases because larger solutes are able to pass through the membrane. The results of the experiment support this because as the pore size increased the filtration rate of the molecules also increased.
2. Which solute did not appear in the filtrate using any of the membranes? Explain why.
Your answer:
Powdered charcoal was the only solute that did not filter using any of the membranes. The charcoal contains large molecules that cannout pass through pores of any of the membranes.
3. Why did increasing the pressure increase the filtration rate but not the concentration of solutes? How well did the results compare with your prediction?
Your answer:
Increasing pressure increases filtration rate because the molecules are able to pass through the membrane more quiclkly. It does not increase the concentration of solutes that pass through the membrane due to the fact that pressure is independent of the number of present molecules. The results of the experiment support this claim, as the pressure increased so did the filtration rate and nothing happened to the concentration.
Experiment Data:
Run Number
Solute
MWCO
Pressure
Filter Rate
Residue
Start Conc.
Filter Conc.
1
Na+ Cl-
20
50
1
present
5.00
0.00
1
Urea
20
50
1
present
5.00
0.00
1
Glucose
20
50
1
present
5.00
0.00
1
Powdered Charcoal
20
50
1
present
5.00
0.00
2
Na+ Cl-
50
50
2.5
present
5.00
4.81
2
Urea
50
50
2.5
present
5.00
0.00
2
Glucose
50
50
2.5
present
5.00
0.00
2
Powdered Charcoal
50
50
2.5
present
5.00
0.00
3
Na+ Cl-
200
50
10
present
5.00
4.81
3
Urea
200
50
10
present
5.00
4.74
3
Glucose
200
50
10
present
5.00
4.39
3
Powdered Charcoal
200
50
10
present
5.00
0.00
4
Na+ Cl-
200
100
20
present
5.00
4.81
4
Urea
200
100
20
present
5.00
4.74
4
Glucose
200
100
20
present
5.00
4.39
4
Powdered Charcoal
200
100
20
present
5.00
0.00

Activity 5:
Review Sheet Results
1. Describe the significance of using 9 mM sodium chloride inside the cell and 6 mM potassium chloride outside the cell, instead of other concentration ratios.
Your answer:
Three Na+ ions are transported out of the cell for every two K+ ions that go in, creating the ratio of 3:2 mM which is the same as 9:6mM.
2. Explain why there was no sodium transport even though ATP was present. How well did the results compare with your prediction?
Your answer:
In order for the Na+/K+ pumps to function, both ions must be present, due to the fact that there was no potassium present the pump was unable to function. The results supported this prediction in showing that there was no soduim transport even with ATP present when potassium is absent.
3. Explain why the addition of glucose carriers had no effect on sodium or potassium transport. How well did the results compare with your prediction?
Your answer:
Carriers are used to transport molecules using facilitated diffusion with no energy usage from any external source. The ions Na+ and K+ are transported actively with their respected pumps against their concentration gradient, thus proving that the addition of carriers would have no effect on the transport of these ions. The results from the experiment support this in showing that adding carriers did not effect the sodium and potassium ion transport.
4. Do you think glucose is being actively transported or transported by facilitated diffusion in this experiment? Explain your answer.
Your answer:
I think that glucose is passively being transported down its concentration gradient via facilitated diffusion because there was no ATP present, thus proving that the glucose carriers were present in assisting the transport of glucose molecules across the membrane.

Experiment Data:
Run Number
Solute
ATP
Start Conc. L
Start Conc. R
Pumps
Carriers
Rate
1
Na+ Cl-
1
9.00
0.00
500
---
0.0188
1
K+ Cl-
1
0.00
6.00
500
---
0.0125
1
Glucose
---
0.00
0.00
---
0
0.0000
2
Na+ Cl-
3
9.00
0.00
500
---
0.0025
2
K+ Cl-
3
0.00
6.00
500
---
0.0017
2
Glucose
---
0.00
0.00
---
0
0.0000
3
Na+ Cl-
3
9.00
0.00
500
---
0.0000
3
K+ Cl-
3
0.00
0.00
500
---
0.0000
3
Glucose
---
0.00
0.00
---
0
0.0000
4
Na+ Cl-
3
9.00
0.00
800
---
0.0042
4
K+ Cl-
3
0.00
6.00
800
---
0.0028
4
Glucose
---
0.00
0.00
---
0
0.0000
5
Na+ Cl-
3
9.00
0.00
800
---
0.0042
5
K+ Cl-
3
0.00
6.00
800
---
0.0028
5
Glucose
---
0.00
10.00
---
400
0.0028#

Conclusion:
I conclude that this lab proved my hypothesis correct. After concluding the lab I now have a full understanding of the topics covered in the chapter “The Cell” and will have a complete understanding of the makeup of the cell and all of its functions.