2006-07-20 19:26:58 · 8 answers · asked by The Knowledge Server 1 in Science & Mathematics ➔ Other - Science
No, many are spontaneous.
2006-07-20 19:31:26 · answer #1 · answered by Anonymous · 0⤊ 1⤋
Our core body temp. is way too cold for chemical reactions to take place or take place at a rate sufficient to cause or maintain life. So most of the reactions in the body use enzymes. There are some reactions that do not, an example is hemoglobin A1c. It turns out that a certain fraction of hemoglobin becomes glycoslated based on concentration and time and is not enzymatic. Because of this, it is used as a prime indicator of long term blood sugar metabolism.
2006-07-21 02:50:05 · answer #2 · answered by mr.answerman 6 · 0⤊ 0⤋
Almost all happen enzymatically. MrAnswerman is refering to reactions which although happen in living organisms they are not of biological use but are rather "aging" reactions.
Even a simple reaction like hydration of carbon dioxide (although it can happen on its own) it is catalysed by carbonic anydrase (H2O+CO2-> HCO3(-) + H(+)
The enzyme speeds up the reaction by a factor more than one million.
Examples of biochemical reactons which are not enzymatic are:
photoinduced transformation of ergosterol to previtamin D3 and its subsequent thermal isomerisation to
vitamin D3
Photoisomerization of cis-retinal to trans-retinal in rhodopsine (first step in the process of seeing light)
Production of hydrogen peroxide with the help of iron ions and quinone by some fungi (Gloeophyllum trabeum) in their extracellular environment.
I am sure there are more...
2006-07-21 12:05:46 · answer #3 · answered by bellerophon 6 · 0⤊ 0⤋
The answer might depend on what you would consider to be "biochemical reactions". Does that category include the weak interactions between molecules such as the binding of hormones to their receptors on cell membranes, or the pH buffering of carbonate: bicarbonate: proteins etc in the blood plasma?
2006-07-21 02:34:09 · answer #4 · answered by J_F_(Self Service Science Forum) 4 · 0⤊ 0⤋
Yes and no. Most biochemical reactions in your body can happen on their own, but by the time they do you'd be dead. So enzymes from your body acts as catalysts to speed up the reaction so that they occur in time for your body to function.
2006-07-21 02:31:20 · answer #5 · answered by Anonymous · 0⤊ 0⤋
no,not all time because enzymes are only bio promoters.
and all biochemical reactoin do not need promotion
2006-07-21 02:36:07 · answer #6 · answered by genius 1 · 0⤊ 0⤋
Need not be.
2006-07-21 03:57:11 · answer #7 · answered by K.J. Jeyabaskaran K 3 · 0⤊ 0⤋
no, naturally can happen
2006-07-21 02:53:26 · answer #8 · answered by cool nerd 4 · 0⤊ 0⤋