Photosynthesis

Hi there readers! I promised my students that I'm gonna upload this video that i presented in class this week. They love this and you might like it too :)

But before that, I'm gonna give you a brief introduction to a plant process called photosynthesis. "Photo" is a Greek word for "light," and "synthesis" means "to combine."  We all get our energy from the food we eat which we get directly or indirectly from plants. How about plants? 

They use this process to make their own food. Photosynthesis can only occurs in the green parts of the plant. Leaves have tiny like structures called chloroplasts which contain a green pigment known as chlorophyll. The function of chlorophyll is to absorb sunlight and takes the carbon dioxide and the water, and turns them into sugar (glucose) and oxygen. The glucose provides the energy for the plant and the glucose can be converted into starch as food to be stored inside the plant. The oxygen which is the by product of photosynthesis will be released to the air through tiny pores called stomata found underside of the leaves.

So, photosynthesis can be defined as a process whereby green plants make food (glucose) using the raw materials carbon dioxide and water in the presence of sunlight. This process also releases oxygen.  Here's the word equation for photosynthesis:

Plants and animals (including us human) need each other to survive. We breathe out carbon dioxide which is needed for the plant during photosynthesis. Plants photosynthesize to make food and oxygen that we need. Other than oxygen used for respiration in living things, photosynthesis is also important whereby the oxygen released is used to purify the air by removing carbon dioxide in the atmosphere which can cause global warming.

Ok ok...enough already. Now it's time for you to enjoy the video. :))

 

Here are the lyrics for you to sing along! You might as well learn the lyrics...It's a fun way to learn! :D

If you want to know,

How a plant grows,

It takes water, air and sunlight,

and makes cellulose...

Every plant can do this,

Fundamental process,

and we can call this,

Photosynthesis!

Unlike me and you,

Plants need CO2,

and they make oxygen,

That stops us turning blue...

Every plant can do this,

Fundamental process,

and we can call this,

Photosynthesis!

It's a miracle,

How all the chlorophyll,

Captures sunlight in the leaves

of the plants and the trees...

A plant of any size,

Can do this if it tries,

But we're not green so we can't

Photosynthesize...

Every plant can do this,

Fundamental process,

and we can call this,

Photosynthesis!

It's a miracle,

How all the chlorophyll,

Captures sunlight in the leaves

of the plants and the trees...

Every plant can do this,

Fundamental process,

and we can call this,

Photosynthesis!

Every plant can do this,

Fundamental process,

and we can call this,

Pho-to-syn-the-sis! (photosynthesis)

Click the link below to test your knowledge of Photosynthesis!

http://www.growingthenextgeneration.com/agrium-games/quiz/index.htm

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Plant and Animal Cells

CELL

Cell is a small unit that makes up living organisms. Living organisms may exist as one cell (unicellular) such as amoeba (an animal) and euglena (a plant) or many cells (multicellular) such as man, cat and rose.

PLANT AND ANIMAL CELLS

What do the parts of cells do?

So that's our lesson for today. Pretty easy, right? Test yourself by clicking these links: 

http://www.proprofs.com/quiz-school/story.php?title=3rd-block-group-2_1#

http://www.curriculumbits.com/prodimages/details/biology/label-the-cells.html

Below are some photos of cell models made by Year 7 students. Click image to enlarge...

Year 7 students making models of a plant cell and an animal cell

Year 7A (Shaathir)

Year 7B (Syaakir)

Year 7C (Syaafiq)

Year 7D (Shaahir)

Year 7E (Saabir)

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Happy 189th Birthday, Gregor Mendel!

Did you see today's google doddle? For those of you who have studied inheritance or genetics might have heard of this name, Gregor Mendel. He is known as the "father of modern genetics".

Here is a biography on Gregor Mendel taken from www.pinkmonkey.com :

"Gregor Johann Mendel was born on July 22, 1822 in Moravia, Austria. He had his early education in a monastery in Brunn, Austria (now Brno in Czechoslovakia) and later studied science and mathematics at the University of Vienna. He graduated in 1840. Mendel returned to the monastery in Brno as a monk. He worked as a teacher of physics and natural science in a Higher Secondary School of Brno during 1854 to 1868. He was appointed abbot of the monastery in 1868 and held this post until his death.

Mendel carried out his legendary experiments on garden pea plants in the monastery garden from 1857 to 1865. He had a clear perspective and worked on the experiments with precision and thoroughness. He published his research paper containing his observations and conclusions in 1866 in the annual proceedings of the Natural History Society of Brunn. These conclusions are now known as Mendel’s Laws. This work is a classic in biology for its elegance and simplicity and ranks amongst the most outstanding biological contributions of all times.

But unfortunately, this work failed to attract the attention of the biologists of that time. Hence, it went ignored for 35 years. One of the possible reasons for such neglect was the inability of the biologists of that time to understand and appreciate the statistical approach adapted by Mendel. Thus, Mendel was left bitterly disappointed, and died an unrecognized death in 1884. 

Sixteen years after Mendel's death, in 1900, Hugo de Vries (Holland), Karl Korrens (Germany) and Von Tschermark (Austria) independently arrived at similar conclusions as those of Mendel. De Vries rediscovered the research paper of Mendel and it was published again in 1901. The experiments on heredity of plants and animals since then have confirmed that Mendel's laws of heredity are applicable to other organisms as well. They form the basis of modern genetics. Hence, Mendel is called The Father of Genetics."

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ARGGHHHH! TOO MUCH PRESSURE!!

Don’t worry peeps…It’s not a stressful topic to learn. In fact, once you've mastered the topic, you can do a magic trick with this air pressure concept. Last week, I showed my students some cool science demos to see the effect of air pressure on an object. You can try these tricks at home but remember NOT TO perform these tricks without adult supervision :) 

1) Crushing a soda can with nothing more than air!

 

HOW DOES THIS WORK?

At first, the soda can was filled with water and air. Then the can was heated to boil the water inside (water changed from liquid to gas). This gas pushed the air inside the can into the atmosphere. When the can was turned upside down and placed in the water, the water vapour condensed creating a partial vacuum. The very low air pressure inside the partial vacuum of the can made it possible for the greater air pressure outside of the can pushed the can and crushed it. This sudden collapsing of an object toward its centre is called an implosion.

2) How to get an egg in a bottle in an “eggciting” way?

HOW DOES THIS WORK?

When the person heats the bottle, it causes the air pressure inside to increase. The egg is then placed in the opening and the air cools, exerting less pressure on the egg than the pressure exerted on the egg by surrounding air in the room. The greater air pressure of the room pushes the egg into the bottle.

 3) Self inflating balloon

  HOW DOES THIS WORK?

A sealed balloon was placed inside a vacuum chamber. As the pressure exerted on the balloon decreases, the balloon expands and takes up the space inside the chamber. When the chamber is opened, the air pressure exerted on the balloon increases and causes the balloon to return to its original size.

So...did you learn anything? How cool was that? Who would've thought learning science could be so much FUN! 8)

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