Biology Lab report

OSMOSIS LAB REPORT INSTRUCTIONS

Write the report in the past tense ALL the way through.

INTRODUCTION

1. A definition of osmosis in terms of solute concentration would be a good background information.

Elaborate on the effect of solute concentration on the rate of osmosis.

2. The question:How different concentrations of sucrose affect the rate of osmosis?

3. The hypothesis: if solute concentration affects the rate of osmosis, then as sucrose concentration

increases in the selectively-permeable membrane (bag), the rate of osmosis…………….

Write the above information in a paragraph.

MATERIALS AND METHODS

Write a paragraph describing what was done to set up and conduct the experiment.

Give basic instructions, a step-by-step guide which would allow someone to accurately repeat the experiment on their own. Mention the materials when describing the methods.

RESULTS

In the result section, you should write a paragraph of results in which you should indicate the trend-line data as well as the class raw data (the percentage of the initial mass of each bag stated in the table of class raw data).

You should also produce a trend- line to present the data. Attach the table of class raw data and your graph to the back of your paper.

The graph and the data table: Can be produced manually on a graph paper or produced by using computer programs. Each Graph and data table must contain a figure number and a printed or typed descriptive caption (see the attached example graph & table)

DO NOT make conclusions or relate your data to your hypothesis in this part of the report.

DISCUSSION

In this section, you should discuss the above data and state if the class data supported or refuted the hypothesis. You should also state your opinion about this experiment and discuss more data to show your opinion.

· In one sentence state if the class data supported or refuted the hypothesis.

· Indicate the trend-line data to show if your hypothesis were supported or refuted.

· What unmeasured factors caused variation in the rate of osmosis even when the value of the independent variable was the same? (Why were there differences in the % of the initial mass of the bags filled with the same sugar concentrations?) Give data examples. Use the class raw data to support your opinion.

Formatting instructions

· Margins: 1 inch on all sides

· Font type: Times New Roman

· Font size: 12 point

· Line spacing: 1.5

· Name and Lab section Number: upper left corner

· Title: Below the lab section number, centered, bold, and all caps

· Page numbers: on the bottom (right side or centered)

· Section headings: bold and all caps

· Total length: Maximum of TWO typed pages not counting tables and graphs.

EXAMPLE

Table 1. Class raw data of the effect of sucrose concentration on the rate of osmosis (% of the initial mass of each bag).

At 0M, the range was 98-115%. There were two values of 103%. At 0.25M, the range was

105-120%. At 0.5M, the range was 111-117%. There were two values of 115%. At 0.75M, the range was 114-129%.

SUCROSE TABLE OF CLASS RAW DATA

CONCENTRATION % OF THE INITIAL MASS OF EACH BAG

0M	103	103	115	102	98
0.25M	120	109	117	110	105
0.5M	115	113	117	115	111
0.75M	129	128	123	116	114