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Introduction to Biology and Lab-BIO105

Lab 4: Surface to Volume Ratio for Cells

Introduction

(Adapted from https://www.biologyjunction.com/cell_size.htm)

Cells are limited in how large they can be. This is because the surface area and volume ratio does not stay the same as their size increases. Because of this, it is harder for a large cell to pass materials in and out of the membrane, and to move materials through the cell.

THE SURFACE AREA TO VOLUME RATIO OF A CELL

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MATERIALS:

Scissors Construction paper Tape Metric ruler

Procedure

1. Construct three cell models like the pattern shown. The dimensions of a side will double each time, with the sides being 2 cm, 4 cm, and 8 cm. Fold and tape into cubes with the tabs to the inside. Record the dimensions in the DA TA TABLE (the first one is done for you in the table).

Cell	Dimensions(cm)	Surface Area (cm2)	Volume (cm3)	Ratio of Surface to Volume
Cell 1	2 x2x2
Cell 2	3x3x3
Cell 3	4x4x4

Lab 4: Cell to volume ratio

Report Sheet

CALCULATIONS:

1. Construct three cell models like the pattern shown. The dimensions of a side will double each time, with the sides being 2 cm, 4 cm, and 8 cm. Fold and tape into cubes with the tabs to the inside. Record the dimensions in the DATA TABLE (the first one is done for you in the table). 

DATA TABLE 1: Cell Size Comparison
Cell	Dimensions (cm)	Surface Area (cm2)	Volume (cm3)	Ratio Surface area to Volume
1	2 X 2 X 2
2
3

 

CALCULATIONS:

1. Calculate the total surface area for each cell model by the following formula:

surface area = (Length X Width) X 6 sides

2. Record the surface areas in the DATA TABLE.

3. 2. Calculate the volumes for each cell model by the following formula:

volume = length X width X height.

4. Record the volumes in the DATA TABLE 1.

4. Calculate the surface area-to-volume ratio for each cell model by the following formula:

ratio =

surface area volume

Record the ratio values in the DATA TABLE 1. These ratios show how many times larger the surface area is as compared to the volume. Notice that it becomes less than one very quickly.

QUESTIONS:

1. Which model has the largest surface area?

2. Which model has the largest volume?

3. Which model has the largest ratio?

4. To maintain life, and carry-out cellular functions, materials must be able to move into and out of the cell. Also, material needs to be able to move within the cell. What might be the advantage of having a large surface area?

 

 

5. What might be the disadvantage of having a large volume?

6. Submit under Moodle:

1. The table is to be filled in with the data from your cube dimensions

2. Include the answers to your question responses to your report for this lab.