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Half-life

Definition

noun, plural: half-lives

(1) Biological half-life, i.e. the period in which the amount of substance inside the living organism is metabolized and eliminated half of its initial amount by normal biological process

(2) (radiobiology) Effective half-life, i.e. the time required for a radioactive material taken in or administered to an organism to undergo radioactive decay and lose half of the amount of its original value

(3) (medicine) The time at which a drug, substance, or chemical is reduced to half of its original amount, effectiveness, or radiological activity in biological fluid


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mitosis and miosis

In a nutshell: Mitosis- The division of a cell to create two identical new cells. Meiosis- The division of a cell into a gamete, carrying half the genetic DNA of a normal cell, to fertilize another gamete (Example, sperm fertilizing an egg)

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by CaptainCovalency
Thu Jul 10, 2014 3:58 am
 
Forum: Cell Biology
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Views: 2407

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by jonmoulton
Fri Apr 11, 2014 2:47 pm
 
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Topic: DNA testing times
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Views: 1399

Re: two different color eyes

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by jkillings62
Thu Mar 06, 2014 5:48 am
 
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by piscilactovegetarian
Fri Feb 28, 2014 12:10 am
 
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by Seth90210
Sun Feb 16, 2014 9:35 pm
 
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Topic: Brain size=IQ level theory (Blacks vs Whites & Asians)
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