Tuesday, November 17, 2009

The Three Major Steps in Cellular Respiration

Glycolysis takes place in the cytoplasm, in aseries of reaction, glucose is broken down into pyruvate. Energy released and trapped in two molecules of ATP. Pyruvate moves into the mitochondrion.

The second major reaction of respiration is called the Krebs Cycle. It is named after the scientist discovered the different steps in the cycle. The Krebs cycle takes place in the liquid part of the mitochondrion here, acetyl coenzyme A (acetyl CoA) w/c is formed from pyruvate enters the cycle. Sveral substances are formed w/c are used again. But three products move out of the cycle. These are carbon dioxide w/c leaves cell, two molecules of ATP, and the hydrogen carrier, AH2.

AH2 passes into the cristae where the third major reaction occurs. AH2 break down into hydrogen and electrons (e). The electrons flow from one electron acceptor to another. As the electrons flow, energy is released forming a total of 32 ATP molecules. The last electron acceptor is oxygen w/c finally forms water with hydrogen.

The simple disscusion illustrates the gradual breaking down of the glucose molecule. Energy is slowly released and captured in ATP. For every molecule of glucose, a total number of 36 ATP molecules are formed.

Wednesday, November 11, 2009

Diffusion

An example of Passive transport is diffusion, the process by which particles spread through a liquid or, a gas medium. In diffusion, the net movement of particles is from a region of higher concentration to a region of lower concentration. In cells, water and alcohol easily diffuse across the plasma membrane.

Saturday, November 7, 2009

Types Of Fertilizers

Natural (organic) ~ made from decayed plants, animals & human waste. Useful in recycling soil nutrients & promotes the growth of helpful organisms.

Artificial (inorganic) ~ produced from petruleum based chemicals w/c are harmful from plants & microorganisms. Theey can also contaminate groundwater source.

Tuesday, November 3, 2009

Water Cycle

When there is a precipitation~whether rain, hail, or snow~water from the atmosphere falls to the Earth. Some of the water reaches the ground and travels to become part of lakes, rivers, or oceans. Other parts sink and form groundwater. Water cycle involves evaporation, condensation, and precipitation. This cycle transform water into different phases.

Science Ideas

* Microtome - is the instrument used to cut specimen very thinly in sude preparation.

* Microforceps - are used to move material and insert a new ones in cells.

* Microelectrodes - measure electric current within cell.

* Micromanipulator - translate arge movement of the hand into microscopic movement.

* Microdissection - is a method of replacing cell organelles like the nucleus to help determine it's function.

* Intermediate Filaments - are studied in the detection of possible origins of cancer.

* Smooth (E.R) - synthesis enzymes involved in detoxitification.

* Cell Membrane and Cytoplasm - are directly preservation of food.

Saturday, October 31, 2009

Who Did It

This is the story about four people named Everybody, Somebody, Anybody and Nobody. There was an important job to be dore and Everybody was asked to do it. Everyone was sure that Somebody would do it. Anybody could dore it but Nobody did it. Somebody got angry about this because it was Everybody's job. Everybody thought Nobody could do it, but Nobody realized that Everybody would not do it. It ended up that Everybody blamed Somebody when actually Nobody accused Anybody.

Friday, October 30, 2009

Carbon-Oxygen Cycle

Plants use carbon dioxide in the air together with dissolved nutrients from the soil to manufacture their food. In the process, the plants produce glucose as stored energy and oxygen as a by-product. Consumers use the stored energy and its by-product. They release carbon dioxide during respiration. This release of carbon dioxide completes the carbon-dioxide completes the carbon- oxygen cycle.