Last lab session continued

This experiment show how is the visking tubing partially permeable.

The first picture shows the results of the experiment. The test tube with the red precipitate is the test tube with glucose and Benedict solution was added to it, turning it red as glucose is a reducing sugar. The second test tube shows iodine being added to the test tube with the glucose solution to test it for starch. The last test tube shows that there is starch in the visking tubing as the iodine turned blue black.

The picture above shows the glucose solution with Benedict solution being heated up. It is being heated up to speed up the reaction.
The experiment is as follows.

1. Place a solution of starch and glucose in visking tube.
2. Place the visking tube in a beaker of water for sometime
3. Drop a few drops of Benedict solution into the beaker to show that glucose has move from the visking tube to the beaker.

From this experiment, I have learnt that the visking tube is partially permeable like the humans intestines. 

Last Lab Sesion

It was our last lab session for the term and we did 2 experiments, one of it was testing for starch on a leaf and the other was the use of visking tubing. 

 The pictures below shows the experiment of testing for starch on a leaf.
The picture on the top right shows the leaves in a hot water bath of ethanol.
At the top left the picture shows the leaf after being tested for starch with iodine. As shown, the green part of the leaf turns the iodine while the yellow part of the leaves make the iodine remains brownish- yellow.

The pictures above shows the ethanol after a leaf is being soaked in it. The ethanol turned green because of the chlorophyll in the leaf.
The steps for this experiment are as below:

1. Boil the leaf to break the structure of the leaf cells
2. Place the leaf in ethanol and place the ethanol in a hot water bath
3. Add a few drops of iodine on the leaf

From This experiment i learnt that for a leaf to photosynthsis it requires chlorophyll and chlorophyll can only be found in the area of the leaf.

The next post will show the other experiment about the visking tubing

The pictures below are the pictures of elements, mixtures and compounds.

The photo shows a box of sulfur, it is an element by itself.

The photo shows a box of iron filings, it is an element by itself too.I have learnt about elements, mixtures and compounds. 

 

The photo below shows the mixture of iron filings and sulfur.

 The photos below shows the compound of sulfur and iron after it is heated.

 I have also learnt that many things are created through different elements and/or  compounds through different methods .For example, sodium and chlorine form salt after the two elements have been processed.

Measurement

The pictures below are those of the vernier caliper and the micrometer screw gauge. 

The micrometer screw gauge is used to measure thing up to 3 decimal point

The vernier caliper is used to measure things up to 2 decimal places in centimeters. 

Critical reviews of contemporary science issues

Genetically Modified Foods: Helpful or Harmful

Personally I feel that genetically modified foods are helpful to feed the growing population in the world. Genetically modified foods can possess many traits which the plant originally did not possess like drought resistance. Stale food crops like rice can be harvested in a shorter time after genetically modifying it and this rice could be sold at a cheaper price which is more affordable by the poor. However, there is also a catch involving Genetically Modified Foods, among them are environmental hazards, human health risks, and economic concerns. If a foreign gene is introduced to the crop it may cause un intended harm to the consumers but I believe if safety precautions are taken it should be quite safe to consume. I truly believe that genetically modified food is the future of our future world where the population is double from the sx million now,

Personal performance

My target for the next class test is A1 and I am going to work hard to attain that.

3ps' to achieve my target

Pay attention

Practise more

Play less

Class test

Mcq 

Be more careful try to score full marks.

                                      Things I learnt beyond textbooks! 

1) Acids and Bases 

Acids

• Tastes sour(E.g. Lemon)
• Changes blue litmus paper to red colour

Basics

• Feels slippery(E.g. Soap water)
• Tastes bitter 
• Changes red litmus paper to blue colour 

The table below shows the pH level scale from 0-14. 

	pH
Acids	0(Lead battery acid)
	1
	2(Gastric acid)
	3(:emon)
	4(Tomato juice)
	5(Coffee)
	6(Urine)
Neutral	7(water)
Bases	8(Seawater)
	9(Household ammonia)
	10
	11
	12
	13
	14

2) Water Pressure

The weight of the water on top creates pressure on the water underneath, which makes water spurt out rapidly when there is an opening. The pressure is proportional to the depth of the water above the opening thus if the hole is placed at the top there would be less water pressure. As the water level drops, there is less pressure, so the flow through the opening slows down.

 

3) How a fan works.

An electric fan is an electric motor with some fan bladse attached to its rotating shaft. As the fan blades rotate, each blade is inclined a bit, and as the inclined plane of the blade moves through the air, it forces the air ahead of it forward. Each blade does this on a continuous basis, and the result is a moving air stream. The fan takes air from the area behind itself and blows it out the front. The fan generates a movement of air, causeing the warm, less dense air to rise, and the cool, dense air to descend, thus creating a feeling of coolness in the air.