Thames & Kosmos Genetics & DNA handleiding

Niet gecategoriseerd

Thames & Kosmos

52 pagina's

PDF beschikbaar

Handleiding

How much DNA is in various foods?

This table shows the quantity of DNA in

ﬁve foods, in grams per kilogram by dry

weight (meaning grams per kilogram of

dried food).

Food Grams of DNA

Calf’s liver 17.3

Smoked trout 1.0

Broccoli 5.0

Potatoes 2.6

Wheat 0.7

WHO DISCOVERED

DNA

Today, we have it easy: We can simply use the freezer to cool

down important experimental solutions, such as the

denatured alcohol. The discoverer of genetic material, on

the other hand, had to get up at ﬁve in the morning for his

experiments, in order to be able to take advantage of the

cool morning temperatures. The Swiss researcher Johann Friedrich Miescher (1844–

1895) was the ﬁrst person to isolate genetic material.

To do it, though, he used sources that were quite a bit less appetizing than

tomatoes. Miescher took white blood cells obtained from pus in the used bandages

of patients. From that, he was able to isolate a ﬁlamentous white substance, like the

one that you isolated, in 1869. Miescher called it nuclein (from the same Latin source

as the word nucleus — researchers liked to use words with Greek or Latin roots,

since they were internationally easy to agree on).

Miescher wasn’t sure, however, what it was that he had isolated. Only after he

repeated the experiment with the sperm cells of salmon (which were common in the

Rhine River at that time, and had particularly large cells, which made it easier to

experiment with them) was he able, in 1871, to publish his ﬁndings. The most

commonly used abbreviation today, DNA, stands for “deoxyribonucleic acid.”

CHECK IT OUT

Isolating Genetic Material | 

Bekijk gratis de handleiding van Thames & Kosmos Genetics & DNA, stel vragen en lees de antwoorden op veelvoorkomende problemen, of gebruik onze assistent om sneller informatie in de handleiding te vinden of uitleg te krijgen over specifieke functies.