DNA part 2_ Replication

DNA replicates itself to make a copy of DNA. It occurs when the cell is about to die or when the cell is replicating. It occurs in the nucleus.   There are two enzymes that help DNA to replicate.  There are DNA Polymerase and Helicase. Helicase unwinds and unzips the DNA. then free DNA nucleotides come in and forms a new DNA and it is back with DNA polymerase. It is a very difficult process. And it is happening inside our body till this moment. Human body is amazing!

DNA_ Deoxyriboneucleic acid

Deoxyribose is the molecule that contains the sugar deoxyrbose. Neucleic is found inside the nucleus (eukaryote) or nucleoid (prokaryote). The structure of the DNA is called double helix. The base has pairing. One is Adenine-Thymine that has two hydrogen bonds   and Cytosine-Guanine that has three hydrogen bonds.

DNA is universal and all organisms contain DNA.

Phospholipids Bilayer

Phospholipid bilayer consists of two of Phospholipid, hence named Phospholipids bilayer. It the major component of the plasma membranes .

It looks like this. ↓
Though the picture is not clear, the orange part is the head of the layer. It is hydrophilic (it loves water). This part is made of phosphate.  The blue part tail of the layer. It hates water (hydrophobic).  This part is made up of lipid. The purple things are called integral proteins. The job of those proteins is to transport molecules in and out of the cell. The green and orange is the peripheral protein. Its job is to recognize other cells and it is also a binding site.

Source of the image: http://library.thinkquest.org/C004535/media/cell_membrane.gif

Glucose, Ribose, Lipids

Glucose is C6H12O6. Ribose is C5H10O5. And polymerization happens between monomers. Image This is the structure of a Ribose.

Image This is the structure of the Glucose.Image Now this is the structure of the Tryclyceride lipid.

Links to these photos: http://img.tfd.com/mgh/ceb/thumb/Structural-formula-for-x3b1-D-glucose.jpg 

Water! H2O!

Well, during the beginning of my IB Bio Class, I learned about the basic properties of Water! Water makes up 70% of our body. And definitely we cannot live with out it. There are three basic properties of water. Those properties are thermal, solvent, and cohesiveness.

First, the thermal property of water is that it cools down an organism. For example, when humans exercise, our body temperature goes up. But then by sweating, the liquid that comes out through the exercise cools us down. Not only sweat cools down our body temperature, but also removes toxic wastes in our body.

The second property is solvent. Water can dissolve substrates. The most common example of water being the solvent is when water dissolves salt. Not only water can dissolve substrates, but also, it can distribute substances through an organism. Blood does that job specifically. It transports nutrients needed for our body through blood like protein, oxygen, and etc.

The last property of water is cohesiveness. Water can attract each other. In my class, I had an experiment on how the water is cohesive. So, first we mixed water with detergent and one we did not. Then we tried dropping water on a coin and counted each of them. The water mixed with detergent was just 25 drops but, pure water was about 59. So we concluded that water is very cohesive.

I guess we need water for our survival. We need water and Water is FANTASTIC!

Emergent Properties

Emergent property is defined as an organ, which is more important than its parts. So like cell -> tissue -> organs -> organ system -> organism. So I guess that if a patient is about to be removed from the life supporting apparatus, the doctor must be sure that the patient is going to die even if the apparatus was on. So for the doctor to make sure that the patient is going to die for sure, he needs to check on his heart and brains and other vital organs that will continue his/her life.

In my personal opinion, if the dying patient is surely about to die within a certain amount of time, I believe that the doctor can remove the apparatus. Some people might say that it is immoral to do that, but until when will they waste the apparatus on dying person, when the apparatus can be used to other patients who have higher chances of living. But in most cases it might depend on the family members and the choice of the patient.



Explain how the properties of water are significant to living organisms.

Water is very significant to living organisms. There are three main properties of water, a coolant,  a transport medium, and cohesiveness. Through sweat, organisms release their heat.  Since water is an universal solvent, it can dissolve any substances. The dissolved material can go around the organism transporting important materials to the organs of the organism. Water can also have a property as a habitat for micro organisms.