Biology laboratory report - 18 August 2011

Problem:

Do seeds grow better when soaked in plain water or salt water?

Introduction:

Scientific method is very useful because it can answer the question and solves the problem that needs to be proofed so that we can get new information. For example, in this experiment, I would like to know whether seeds grow better in freshwater or salt water. The method in the scientific experiment includes forming a hypothesis, deciding and controlling variables, interpreting data and deciding an experiment.

Hypothesis:

If I soak seeds in salt water then the seeds will not grow at all.

Materials:

-          2x100 ml beakers

-          40 peanuts

-          Balance scale

-          Salt

-          Water

-          2 paper towels

-          1x50 ml graduated cylinder

-          2 self-sealing plastic bags

-          Masking tape

Procedure:

-          First, pour 50 ml water to both beakers, then mark both beakers one ‘saltwater’ and one ‘freshwater’

-          Add salt to the beaker which is labelled with ‘saltwater’

-          Put 20 peanuts in each beaker

-          Leave them for 24 hours

-          The next day, pour out the water from both beakers and wrap the seeds with damp paper towel

-          Place the paper towel into a plastic bag which has already labelled with saltwater and freshwater

-          The peanuts from saltwater beaker stored in the saltwater plastic and the peanuts from freshwater beaker stored in the freshwater plastic

-          Leave them for another 24 hours

-          The following day, open both plastics to check the result

-          Count the number of the seeds which are growing in each plastic

Results:

	Seeds used	Seeds that grew
Freshwater	20	7
Saltwater	20	0

1.      Under what condition, plain water or salt water, did more seeds grow?

The seeds grow more in plain water

                      

2.      Under what condition, plain water or salt water, did few seeds grow?

The seeds grow less in salt water

Analysis:

1.      Is your original hypothesis supported by your data? Why or why not?

Yes, my hypothesis is supported by my data because we can see from the table results that there are 7 seeds grown in freshwater whereas no seeds grown in saltwater

2.      How can you be sure that the conclusion you reached is correct?

I am sure that my conclusion is correct because it is supported by the result and the article that I researched before the experiment

3.      What variable was being tested in this experiment? What was the control?

The variable was the seeds which was soaked in saltwater and the control was the seeds which was soaked in freshwater

4.      How do salt water and plain water affect seed growth?

The salt water does not support the seed to grow because salt water is osmosis which affects the absorption system so the seed can’t absorb the water properly. Other than that, salty water has a bit high temperature which is not the right temperature for seeds to grow. On the other hand, seeds can grow in plain water because the seed can absorb the water properly and has the right temperature.

Conclusion:

The seeds will grow better when soaked in plain water because to grow the seeds need oxygen, which can be found in the plain water and also the seed can absorb the water properly as well as the plain water has the right temperature for seeds to grow. The seeds will not grow at all in salt water because salt is an osmosis so it affects the absorption by the seeds and also it is not the right temperature for seeds to grow. It was seen from the result from this experiment that no seeds grown in the salt water at all.