choice questions
( Volume of the oxygen which is important for life is
(b) 1/15of the air (C) 1/10 of the air
(a) 1/8 of the air
Answers
Answer:
What creates the need for oxygen in our bodies?
How do I get the honey without harming the bees?
Flowhive is one such product. It consists of frames with breakable combs which are driven by lever. One just have to pull the lev
To explain why we need oxygen one most first understand how metabolism works. The overall reaction for metabolism is:
Glucose (C6H12O6) + 6 O2 --> 6 CO2 + 6 H2O + Energy
Obviously, oxygen is necessary for this reaction to occur, but why?
In reality this reaction is a oversimplification, and is really made up of many different smaller chemical reactions. To keep things as simple as possible, the cells in our body have organelles called mitochondria, which are commonly referred to as the "powerhouse of the cell." Mitochondria are responsible for generating most of the energy we use. For cells the energy that is produced is used to build a molecule called adenosine triphosphate (ATP). ATP is like the energy currency of the cell. As you probably guessed ATP has three phosphates in it, and each time you take one of the phosphates off of ATP you release a bunch of energy that can be used to carry out many of the important chemical reactions in our body. Basically the reaction is like:
ATP --> ADP (adenosine diphosphate) + Phosphate + Energy.
To produce ATP the mitochondria in our cells use a bunch of enzyme to pump hydrogen ions (H+) from an inner compartment called the matrix into an outer compartment called the intermembrane space. When we pump the hydrogen ions into the intermembrane space the concentration of H+ in that compartment rises so the H+ ions want to naturally diffuse back into the matrix until the concentrations in both compartments are equal. However this is prevented because H+ cannot go through the membrane separating the compartments. Instead the H+ is only able to flow through an enzyme called ATP synthase that works like a motor that sticks a phosphate to an ADP to create new ATP. The H+ flowing through the enzyme works kind of like of like a watermill where with H+ ions acting like the water. This "watermill" turns some gears that force one phosphate and one ADP so close together that they stick to make a new molecule of ATP.
In order to create the H+ needed to power our watermill, we use two molecules called FADH and NADH.
NADH-->H+ + (NAD+) + 2e-
FADH-->H+ + (FAD+) + 2e-
In the end our mitochondria need to do something with those left over electrons because if they are allowed to just float around they will immediately react with whatever random molecule they happen to find first which would be bad. This is where oxygen comes in. Based on its position in the periodic table oxygen loves electrons. Oxygen will take electrons from whatever it can find which makes it a pretty convenient molecule to dump those extra electrons onto. We give the extra electrons O2 which reacts some of the extra H+ laying around creating the water molecules you seen in the overall reaction. So basically we need oxygen because it lets us get rid of left over electrons from generating ATP.
It is important to note that not all organism do this all time. For example if you are using ATP faster than you can breathe oxygen (like if you are sprinting or holding your breather underwater) your body starts using a molecule called pyruvate instead of oxygen to get rid of the extra electrons. This produces lactic acid which is what causes your muscles to burn when you exercise.
Different organism do slightly different things. For example when yeast don't have enough oxygen they also use pyruvate to get rid of their extra electrons, but instead of making lactic acid, they make ethanol (alcohol) which is how beer and wine are made.
Also what Dipkanya Das said about oxygen being essential for life is not really true. Oxygen is require for use and all other animals to survive, but for some bacteria (like the ones in your gut that help you digest food) oxygen is too electron hungry actually kills them because it steals electrons from things it is not supposed to. Even for humans, breathing 100% for an extended period of time is not good for us because it can react with so many things inside our body if the concentration gets too high.