what causes glucose to convert to lactic acid?

Answer 1

After you eat your body turns carbs into glucose which is used by the body for energy, glucose that is not readily used is then broken down into glycogen, glycogen is then stored in your liver and muscles, but it has limited storage capacity so any left over blood glucose will be stored in adipose tissue ( fat tissue) and the body unffortunetly has unlimmited capacity for adipose tissue ( hence obesity). During exercise the body will use glucose in the blood stream for energy, when that is depleated it will then go for its glycogen stores which creates a by product of lactic acid ( this is why you have sore, stiff muscles) it takes 24-48 hours for the lactic acid to be re-absorbed and soreness will aleviate. Your glycogen stores will automatically be repleated. I hope this helps.

Answer 2

As it turns out, lactic acid is actually our friend. It is responsible for helping to create more ATP - (Adenosine tri-phosphate. A high energy phosphate molecule required to provide energy for cellular function. The energy source your muscles use for short bursts of power)- and is more efficient at travelling between tissues (like our muscles) than glucose (the sugar ATP is made from.) muscle cells convert glucose or glycogen to lactic acid. The lactic acid is taken up and used as a fuel by mitochondria, the energy factories in muscle cells. Lactic acid is constantly formed in and reabsorbed by our muscles all day long, but at much higher levels when we engage in very intense efforts, also known as anaerobic activity. (anaerobic = no oxygen) During anaerobic glycolysis (the process of using/breaking down glucose as ‘fuel’ for our muscles) the glucose gets broken down to lactic acid and hydrogen ions. This is the surprise: it’s actually the hydrogen that causes problems! As it gets into the muscle tissue and surrounding blood, it creates an acid imbalance, which then leads to pain and discomfort and muscle fatigue. The lactic acid works in our favour once more, by helping to carry the hydrogen away, where it gets removed in the liver. Also, the lactic acid is used in the liver to form more glycogen.
I add a link that has details of this subject

http://www.sparknotes.com/
testprep/books/sat2/biology
/chapter6section1.rhtml

Hope this helps
Matador 89
P.S.
I note that Peruvic acid has been mentioned, and I add a small amount of further explanation to that of “Dr.Salim”. - Peruvic acid is the end product of the glycolytic pathway. This three-carbon metabolite is an important junction point for two reasons: it is the gateway to the final common energy-producing pathway, the Krebs cycle; and it provides acetyl coenzyme A (acetyl CoA), through which fatty acids, and in turn fat, are produced from glucose. Pyruvic acid converts to lactic acid as needed. Pyruvic acid increases in quantity in the blood and tissues in Thiamin (vitamin B-1) deficiency.

This link has details of pyruvic acid
http://www.biology-online.
org/dictionary/Pyruvic_acid
m.89

Answer 3

Lack of oxygen. Lactic acid is the anaerobic product of glycolysis (metabolism of glucose).

Answer 4

Lack of Oxygen ! Normally glucose is converted to Pyruvic acid and then pyruvic acid is further metabolized, but lack of oxygen blocks further metabolism of pyruvic acid and pyruvic acid is converted to lactic acid. this event is observed in exerting muscles and those tissues where blood supply is lacking (ischeamic tissues).