Bacteria perform important functions in the soil, decomposing organic residues from enzymes released into the soil. Each functional bacteria group plays a role in recycling soil nutrients.
Answer: The bacteria transformed with this particular plasmid will form white colonies on the plates containing ampicillin and Xgal.
Explanation: The lacZ gene produces an enzyme called β-galactosidase which is responsible for the breakdown of lactose into glucose and galactose. The lacZ gene is one of the three genes (the other two being lacA and lacY) of the lac operon which is responsible for the transport and mechanism of lactose in E. coli and many other bacteria.
In recombinant DNA technology, when a plasmid is to be used to transform a host cell, such markers are used to help screen the transformed cells from the ones that have not taken up the plasmid. Xgal present in the plates is an artificial substrate which is hydrolyzed by
β-galactosidase into 5-bromo-4-chloro-indoxyl which will dimerize and oxidise into 5,5'-dibromo-4,4'dichloro-indigo. This is a blue pigment which will give blue color to the bacterial cells. Introducing a DNA fragment in this lacZ gene will make it non-functional so it will not be able to produce the enzyme.
Therefore, when a bacterial cell is transformed with a plasmid containing ampicillin resistance gene and a DNA fragment introduced in the lacZ gene and then grown on plates containing ampicillin and Xgal, white colored colonies will appear. The white colonies will show the bacterial cells that have successfully taken up the plasmid with the DNA fragment incorporated in the lacZ gene as this will render the gene non-functional and will not produce β-galactosidase which will breakdown Xgal to give blue colonies. Since the plates contain ampicillin, only the bacterial cells that have been successfully transformed with the plasmid ( the ones that have the DNA fragment and the ones without it) will grow as the ampicillin resistance will give them resistance against ampicillin in the plates. The bacterial cells that have not taken up the plasmid will not be resistant to ampicillin and will not form colonies on the plate.
This is called blue-white screening which is used to identify successfully transformed host cells. A picture of this is given in the attachment, taken from the following website:
https://www.mun.ca/biology/scarr/Blue_&_White_Colonies.html
Answer:
1100
Explanation:
There is 10% of total energy in each increasing trophic level. 10,000 / 10 = 1,000 ,so there are 1,000 units of energy in trophic level 2.
1,000 / 10 = 100, so there are 100 units of energy in trophic level 3.
1,000 + 100 units of combined energy would be 1,100 units of energy.
Hope this helps!
Answer:
Extraction of genomic DNA
Explanation:
Resuspend the cells(any number), smaller numbers also work, in 10-20 ul of TE buffer or milli Q water. boil for 5-10 min in a waterbath, quick chill, short spin. use the supernatant as a template for PCR.
If cells are very less, u can directly add cells to the PCR reaction without enzyme,boil for 5-10 min in a waterbath, let it cool slowly, short spin. Add enzyme to the supernatant and start the reaction at extension step followed by normal PCR reaction steps.
Because neurones will not function properly neither will neuroreceptors if a person lacks neurotransmitters, these two parts (transmiters and receptors) all work together and depend on eachother.
Neurones are resposible for transmitting informations trought the body, and if neurotransmitters are no-existent, information may not be able to get to some body parts since neurotransmitters transmit the information.
Hope it helped,
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