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4 years ago

Benzedrine, methedrine, and dexedrine are all __________.

2 answers:

7 0

<span>Benzedrine, methedrine, and dexedrine are all amphetamines, Amphetamines are a stimulant drug to the central nervous system, usually produced in a laboratory. They are used in the treatment of hyperactivity disorder, narcolepsy and obesity amongst other things. They are also present in some banned substances for recreational use.</span>

NNADVOKAT [17]4 years ago

6 0

amphetamines ( just took the quiz )

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Drag each label to the correct location on the chart.

tester [92]

Answer:

jdhnv.

Explanation:

xdjbvjkxbckjv

4 0

3 years ago

What is the soure of energy that drives photosynthesis? A. Sunlight b. Hydrogen ions c. Electrons d. Oxygen

Afina-wow [57]

Answer:

Explanation:

Energy is from the sun. The sunlight causes plants to grow. Sorry h avent done science is a while.

5 0

3 years ago

How do you write 2-3 paragraphs on evolutionary history/advances from the monerans to protists to fungi?

Lyrx [107]

Kingdom Monera was the oldest kingdom of living organisms. The organisms in the kingdom were simple, single celled and their cellular organelles were not covered by membranes. Prokaryotic bacteria were the first known Monerans. However, scientists think that Monerans were evolved into more complex eukaryotic organisms (Protists) with the passage of time.

But how did Monera (Prokaryotes) was evolved into Protista (Eukaryotes)?

Monerans to Protists

Protista are eukaryotes, unicellular or simple multicellular organisms.Many theories were proposed for this evolution, but one that makes most sense was endosymbiotic theory. According to this, the first eukaryotic cells were evolved when two prokaryotic cells existed in an endo-symbiotic relationship. Larger prokaryotic cells engulfed smaller prokaryotic cells. The smaller cells got shelter and nutrients from larger cells and both co-existed in a mutualistic relationship. Both cells eventually evolved into organelles and got never aparted. This is how more complex organisms’ protists were evolved from simple monerans. It was a gradual process and took millions of years.

Protists to Fungi

The earliest fungi were single-celled organisms that contain a flagella to move from one place to another. Recent studies indicate that fungi belong to a group of organisms which were evolved from protists over the course of time. These studies are based on the nucleotide sequence of fungi that matches to a large extent with old protists. It is estimates that fungi evolved 600 million years or even before.

3 0

4 years ago

yellow flowered plant is crossed with red one; some of the offspring had orange color phenotype . explain what happened?

allochka39001 [22]

Answer:

incomplete dominance

Explanation:

the offspring is different from the parent

8 0

3 years ago

A DNA fragment is introduced into the lacZ gene of a plasmid, which also contains an ampicillin resistance gene. What is the app

zhenek [66]

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

8 0

3 years ago