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Found Geneticist 11 times.

Displaying results 1 to 10.

1. Bacteriophage lambda
A bacteriophage (a virus which infects bacteria ) that infects E. coli . It has a complex set of regulatory mechanisms to determine whether it will quietly insert its DNA into the bacterial genome to become dormant and to be reproduced whenever the bacterium reproduces (to lysogenize ), or whether it will hijack the bacterium's cellular machinery to reproduce itself and prepare to infect more bacteria, causing the bacterium to self-destruct shortly after infection (to lyse ). Lambda is particularly useful to geneticist s because parts of it can be used to introduce foreign DNA into the bacterial genome; it is a cloning vector .

2. Bacteriophage T7
A bacteriophage (a virus which infects bacteria ) that is useful to geneticist s because it has a very strong promoter region which strongly encourages transcription of its gene by specific T7 RNA polymerase . geneticists can take the part with the promoter and attach their own genes of interest to it so that they can control transcription rates of their gene by choosing the amount of the RNA polymerase to put in.

3. Beadle, George W.
b. 1903, d. 1991. An American geneticist who won the Nobel Prize in 1958 with Edward Tatum for showing that gene s are responsible for controlling the production of enzyme s.

4. Caenorhabiditis elegans
This is a free-living (non parasitic) species of nematode which makes a good model organism for biological study because it has a small genome of only six chromosome s. It also has a short generation time of about three days (at room temperature), and is easy to grow at high densities (up to 10,000 worms on one Petri dish). C. elegans has been thoroughly studied by geneticist s, developmental biologist s and neurologists. The worms can be used to study genetic manipulation , gene therapy , and the molecular basis of differentiation during development. Much of the world's knowledge about aging, inheritance, and the factors which control gene expression during development comes from studying this and other nematodes. The full taxonomic classification of C. elegans is: kingdom Animalia, phylum Nematoda, class Secernentea, subclass Rhabditia, order Rhabditida, family Rhabditidae.

5. Copy number
* The number of copies of a particular sequence of DNA , a particular gene , or a particular set of genes, in the haploid genome of an organism. * The number of plasmid s per bacterium . Plasmids which are replicated easily and often are called "high-copy-number plasmids"; plasmids which are more strictly controlled in their replication are called "low-copy-number plasmids." The different types have different uses to a geneticist.

6. Crippled strain
A strain of bacteria , typically highly pathogen ic, that has been genetically engineered so that it can't survive on anything but a very specialized medium of nutrients; this is done so that geneticists can experiment on certain pathogens without the risk that they will escape from the lab.

7. Crown gall plasmids
A plasmid , or type of circular DNA , found in the bacteria Agrobacterium tumefaciens which infects dicot plants. Part of the plasmid inserts itself into the plant genome and causes tumors to form in the roots or in the stems nearest the roots. The plasmid has been used by geneticists, minus the tumor-causing parts, as a vector towards the genetic engineering of plants.

8. E. coli (Escherichia coli)
A common bacterium that has been studied intensively by geneticists because it has a small genome and is usually harmless and easy to grow.

9. Haldane, J.B.S.
J.B.S. Haldane was born in 1892, died in 1964. He was a British geneticist and author who wrote many works of popular science.

10. Johansen, Wilhelm
A Dutch geneticist who lived from 1857 to 1927; he coined the word " gene " and demonstrated that environmental adaptations are not inherited.


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