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viridianswan521Lv1

28 Sep 2019

Please, I need help finding three animals that can cause any form of stomach disease (or has an impact on the human stomach in any way, shape, or form). For all three, I need to know the:

Organism Name:

How they fit in with topic:

Classified Group:

Two distinguishing characteristics of the phyla:

Information Cited:

Thank you so much!

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Nestor RutherfordLv2

28 Sep 2019

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2.Conclusion:

What have you learned from your study?

Interpret your data/ results:

Do your results support of disprove your hypothesis?

Compare and contrast your result with those of previous research.

Significance of the results: âBig Pictureâ

What is the global impact of your results?

What questions remain unanswered?

What kinds of experiments can come out of your study?

i have lab for biology and i need help with the Lab Report

the lab name is Bacterial Transformation Lab

1. Introduction:

Introduce the background and the nature of the problem your experiment is investigating.

Summarize the current knowledge of your subject.

Use examples of other research that have examined the same or a similar topic as your experiments.

Ending your introduction:

State your hypothesis

State your predictions

Give a brief statement about how you tested your hypothesis.

please help me with it is important for my lab class tomorrow

that is the lab i put the info please help me for the intro and for number 2 please be clear please

i would be happy if you help me it is due tommorrow i realy need your help on the intro and number 2 please be clear and show clear work hope you do it because it is due tomorrow

Bacterial Transformation Lab

Genetic engineering is one of the newest applications of basic knowledge in biology. It involves the isolation of specific genes from one organism and the insertion of those genes into a second organism of the same, or even different, species. Remember that a gene is a piece of DNA which codes for a product, usually a protein, which gives an organism a particular trait. The development of these techniques has generated considerable excitement and answered many questions, but it has also raised questions. Many scientists and others see genetic engineering as offering opportunities to make life better, for example, by exploring how genes are regulated, by curing diseases of genetic origin, by adding desirable traits to agricultural crops such as the ability to fix nitrogen in corn and pest resistance in cotton, and by genetically altering bacteria with genes enabling them to digest oil spills.

For almost 100 years, it has been possible to isolate DNA from cells, but only in the last 40 years or so has its function been understood. Your textbook discusses the work of such investigators as Fred Griffith and Oswald Avery, who demonstrated that if DNA was isolated from a pneumonia-causing strain of bacteria and added to cultures of nonvirulent bacteria, the recipient cells were transformed into virulent types that caused pneumonia. These transformation experiments were the first to show that genes could be artificially transferred in the laboratory. Since the time of those experiments (Avery's work was done in the 1940s), our knowledge of gene structure, function and control has increased astronomically. The application of this knowledge has created the field of genetic engineering.

Modern genetic engineering techniques depend on three critical factors:

A suitable host organism in which to insert the foreign gene;

A vector to carry foreign genes into the host; and

A means of isolating the host cells that have taken up the foreign gene.

The host organism

The most commonly used host organism is the gut bacterium Escherichia coli (E. coli). Its chromosome is a single large circular DNA molecule, called the genomic DNA, containing about 4 x 10⁶ base pairs. Not every cell will take up foreign DNA when exposed to it, but E. coli grows rapidly, dividing in less than 20 minutes, so that a single cell can give rise to a billion genetically identical descendants in a matter of 10 hours. Thus, a few transformed cells can provide a large number of offspring within a day. The strain we are using is K-12.

The vector

A vector is a DNA molecule used as a vehicle to carry genes from one organism to another. This DNA molecule can be modified by gene-splicing techniques using restriction enzymes and ligases so that it carries the genes of interest (essentially a cut-and-paste operation). Sometimes viruses are used as vectors, but for E. coli, plasmids are often used. A plasmid is a small circular DNA molecule containing 1000 to 200,000 base pairs. Plasmids exist naturally in many strains of E. coli and other bacteria. Plasmids replicate as the cell grows, independent of replication of the genomic DNA. These plasmids are transmitted to each of the product cells during cell division. Plasmids carrying genetic information that is beneficial to the host cell are maintained in a given population by natural selection. Plasmids frequently carry genes that confer antibiotic resistance, an obvious benefit.

When E. coli cells are exposed to plasmids or any other foreign DNA, some of the cells, called competent cells, will take up the DNA. We can induce cells to become competent by treating them with divalent cations, such as Ca⁺⁺, followed by a brief exposure to high temperature, called a heat shock treatment. Exactly how this treatment causes cells to become competent is not understood, but it is described as making the membranes "leaky" so that large DNA molecules (like plasmids), which would not normally pass through the cell membrane, can enter the cell. This treatment does not make all cells competent, but it greatly increases the number of competent cells. Once in a cell, the plasmids replicate and are passed to the product cells during cell division.

The selective medium

The last requirement for genetic engineering is a means of isolating host cells that have taken up the gene of interest. The techniques used depend on the growth requirements of the host organism. For example, each species of bacteria has particular nutrient requirements. The composition of the growth medium (agar or broth) can be modified to allow growth of only certain bacteria -- for example, by adding or removing nutrients or other chemicals from the medium mixture. This modified medium is called a selective medium, because it selects for the growth of only some species. By introducing an antibiotic such as ampicillin into the medium in which the bacteria are grown, you will select for growth of only those bacteria carrying the antibiotic-resistance gene on newly acquired plasmids. In a matter of days, billions of antibiotic-resistant cells, all with the plasmid, can be grown.

Genetic engineers use a modification of this technique to insert a foreign gene into E. coli. In simplified terms, the plasmid (already carrying an ampicillin resistance gene) is modified by inserting the gene of interest. The gene of interest has been isolated from another source; for example, the gene for human insulin has been isolated from the human genome. The modified plasmid, carrying the inserted gene, is then mixed with competent E. coli and the bacteria are placed in a medium containing ampicillin. Only those cells that have the plasmid will grow in the medium, and they are also the cells carrying the insulin gene (in their plasmids). These selected cells can now be used to manufacture insulin, which can be used for insulin therapy by diabetics.

The genes

In the following experiment, you will insert a plasmid into E. coli. The plasmid you will use carries the gene bla, which codes for a protein (beta-lactamase) that is secreted by the bacteria, inactivating the ampicillin in the agar and allowing for bacterial growth. The plasmid also carries an indicator gene. The indicator gene we are using was isolated from a bioluminescent jellyfish, Aequorea victoria. It codes for Green Fluorescent Protein (GFP).

The GFP gene has been modified to include a regulator system that can be used to control the expression of the gene. Gene expression in all organisms is carefully regulated to allow for adaptation to differing conditions and to prevent wasteful overproduction of unneeded proteins. The genes involved in the breakdown of different food sources are good examples of highly regulated genes. For example, the sugar arabinose is both an energy source and a carbon source for bacteria. The bacterial genes that make digestive enzymes to break down arabinose for food are not expressed when arabinose is not in the environment. But, when arabinose is present, these genes are turned on. When the arabinose runs out, the genes are turned off.

Arabinose initiates transcription of these genes by promoting the binding of RNA polymerase. In the genetically engineered pGLO DNA, some of the genes involved in the breakdown of arabinose have been replaced by the jellyfish gene GFP. When bacteria with this plasmid are grown in the presence of arabinose, the GFP gene is turned on and the bacteria glow green in UV light. When arabinose is absent form the growth medium, the GFP gene remains turned off and the colonies appear white. This is an example of the central molecular framework of biology in action: DNA ? RNA ? protein ? trait.

In summary, you will render E. coli cells competent to take up plasmid DNA. The plasmid carries two identifiable phenotypic markers:

The beta-lactamase or bla gene codes for resistance to the antibiotic ampicillin. We will use this to select for bacteria that have taken up the plasmid.

The pGLO gene codes for Green Fluorescent Protein (GFP), which is switched âONâ if arabinose is present.

Safety Procedure

For your own safety and the safety of others, it is essential that you follow all instructions about handling bacteria and disposal of materials. When you finish work for the day, swab your table with disinfectant. WASH YOUR HANDS thoroughly with soap before leaving the lab for any reason, and at the end of the day after you have cleaned your table. Report any spills to your instructor.

List of Materials

Prepared agar plates (2 LB, 2 LB/amp, 1 LB/amp/ara)

Transformation solution (50 mM CaCl₂, pH 7.4)

LB broth

1 pack of inoculation loops

Sterile transfer pipets

1 foam microtube holder w/ tubes

E. coli starter plate

1 red biohazard bag for loop disposal (common use â Loops/pipets only - NO PAPER!!!)

beigefox320

As you may recall in the work of Triplett (1898), the presence of others in a bicycle race was found to enhance individual performance. This is called social facilitation (Williams, Harkins, & Karau, 2007). At times, however, the presence of others can detract from individual performance, which is termed social inhibition (Crisp & Turner, 2007). Similarly, social loafing can occur when an individualâs performance within a group decreases due to his or her reliance on others in the group (Crisp & Turner, 2007).

For this Discussion, review the media program, Week 5: The Virtual Office. Focus on the characters in the media and determine which characters displayed social facilitation, social inhibition, and social loafing.

With these thoughts in mind:

Post by Day 3 a description of the characters in the media program demonstrating social loafing, social inhibition, and social facilitation. Explain how you identified them. Then, select one of the characters and, using the current literature, explain two ways you might mitigate their behavior.

Media Program

(Onscreen Text: The employees at the United Cardboard Company often work individually on projects, but as with most environments, they are occasionally asked to participate in group projects. One such group is about to meet right now to plan a presentation for the Board of Directors. Observe the conversation and reactions of various group members to determine which group members exhibit signs of the following: Social Loafing, Social Inhibition, and Social Facilitation.)

(Interior of an office. Ken stands at the front of the conference room.)

KEN: OK, I guess we might as well all get started. As we all know, the big man has requested the five of us to get together and write and conceptualize a presentation to the board on our new packaging system. Maybe we can start by going around and throwing out some initial ideas.

KATHY: Sounds good to me. I think a PowerPoint presentation would do the job well.

GAVIN: I agree. We could follow it up with a physical demonstration of how the packaging looks and folds-- maybe a video of the larger pieces that won't fit into the boardroom.

KEN: Sounds perfect to me. Amanda, Brian, what do you guys think?

BRIAN: Yeah, what you guys said sounds fine.

(Amanda thinks, âI donât know what to say!â)

KEN: Amanda?

AMANDA: I don't know. I didn't really get much chance to think about this. We only found out we needed to do this together three days ago.

KEN: OK, no worries. Let's focus on the PowerPoint idea. I've been doing a lot of them lately, so I'm happy to take the lead on the design aspect. What do you guys think we should all incorporate into the slides?

GAVIN: I think we should start with where we got the idea for this new packaging -- the company that designed it and the different sizes that it comes in.

KATHY: We should follow that with a graph comparing the old prices to the new ones to illustrate how much we'll be saving over time. Amanda, didn't you have most of that information collected at some point?

(Amanda thinks, âOh no! What if I deleted that?)

AMANDA: I don't know, maybe, it's been so long. I didn't think I'd need it again for a group project like this.

(Gavin thinks, âI wonder whatâs gotten into her. Sheâs not usually this tense.â)

KEN: That's OK, Amanda, I'm sure we can easily dig it up again. Brian, do you have any other ideas for the PowerPoint slides?

BRIAN: Nah, I think what you guys mentioned sounds right.

(Kathy thinks, âWow. Way to contribute Brian.â)

KEN: OK then, Kathy and Gavin why don't you send me all of the info and I'll write it up and make the slides. Amanda, don't worry about the cost saving document, I'm sure I can dig it up from my old emails and put it into that slide too.

AMANDA: Are you sure? I'm happy to look. I mean I'm sure I have it somewhere. (Kathy thinks, âShe really needs to get it together. Why is she so nervous?â) At least I think I have it somewhere. You won't tell the Board of Directors if I lost it, will you?

KEN: Of course not, we're in it together. So as I was saying, I'll write up and prepare all the PowerPoint slides. Then we can start our presentation with reading and explaining each slide. Then, what?

KATHY: Well, and then I think we should show them the packaging live, and the quick deconstructing techniques.

KEN: Great idea. You and Amanda can demonstrate the folding, while I narrate what you're doing.

(Amanda thinks, âIs he doing too much of the work? And what if I drop everything while heâs talking?â)

GAVIN: And after you all demonstrate the smaller packaging, we could show a quick video of how the really big ones function down at the warehouse. Brian, would you be able to go film that quickly one of these days?

BRIAN: I don't really have any experience with video cameras or anything like that, so...

(Gavin thinks, âI should have seen that one coming.â)

KEN: That's OK. My wife actually just got me this great little camera for our anniversary. It takes great videos. So I can just run down to the warehouse, get some footage, then put it together on this new editing software I just downloaded. Maybe add a little music. It's going to be really slick!

KATHY: Are you sure, I wouldn't mind doing that too.

KEN: Oh no, it's fine. I love this kind of stuff; just leave it to me. But I suppose that's enough planning. Now it's time to get to work and make the presentation a knock out. Go team!

What exactly was Hooker's response to Darwin's, Origin of Species? Thank you for your help. I need help deciphering what his opinions truly were.

Hooker, J. D. 1859. [Review of] On the origin of species. Gardeners' Chronicle (31 December): 1052. Part 1.

From the above expressions it will be inferred that we have risen from the perusal of Mr. DARWIN'S book much impressed with its importance, and have moreover found it to be so dependent on the phenomena of horticultural operations, for its facts and results, and so full of experiments that may be repeated and discussed by intelligent gardeners, and of ideas that may sooner fructify in their minds than in those of any other class of naturalists, that we shall be doing them (and we hope also science) a service by dwelling in some detail upon its contents. Thus much we may premise, that it is a book teeming with deep thoughts on numberless simple and complex phenomena of life; that its premises in almost all cases appear to be correct; that its reasoning is apparently close and sound, its style clear, and we need hardly add its subject and manner equally attractive and agreeable; it is also a perfectly ingenuous book, bold in expressions as in thought where the author adduces what he considers clear evidence in his favour, frank in the statement of objections to the hypotheses or conclusions founded on its facts and reasonings; and uniformly courteous to antagonistic doctrines. In fine, whatever may be thought of Mr. DARWIN'S ultimate conclusions, it cannot be denied that it would be difficult in the whole range of the literature of science to find a book so exclusively devoted to the development of theoretical inquiries, which at the same time is throughout so full of conscientious care, so fair in argument, and so considerate in tone. . . . Hitherto most [naturalists] have, as we have already observed, contented themselves with the hypothesis that they were independently created, and the minority have clung to the only other explanation hitherto conceived, that they have all been created by variation from a single first-created living organism, or a few such. Now it must be borne in mind that both these views are mere hypotheses in a scientific point of view; neither has any inherent or prescriptive right to a preference in the mind of the impartial inquirer; but the most superficial observation will show that the hypothesis of original creations is incapable of absolute proof, except the operation be witnessed by credible naturalists, and can only be supported by facts that are either not conclusive against the opposite doctrine, or may be regarded as equally favourable to it; and this hypothesis is hence placed at a disadvantage in comparison with that of the creation of species by variation, which takes its stand on the familiar fact that species do depart from the likeness of their progenitors, both in a wild and domestic state. On the other hand the hypothesis of creation by variation labours under the disadvantage of being founded upon a series of phenomena, the action of each of which individually, as explained by Mr. DARWIN, would appear to prevent the possibility of species retaining their characters for any length of time, and it therefore appears at first sight opposed to the undisputed fact, that many hundreds of animals and plants have transmitted their characters unchanged (or nearly so) through countless generations, and covered, even within the historic period, many square miles of country each with millions of its exact counterpart. To explain this anomaly and to raise this hypothesis of creations by variation to the rank of a scientific theory, is the object of Mr. DARWIN'S book, and to do this he has endeavoured to invent and prove such an intelligible rationale of the operation of variation, as will account for many species having been developed from a few in strict adaptation to existing conditions, and to show good cause how these apparently fleeting changelings may by the operation of natural laws be so far fixed as to reconcile both the naturalist and the common observer to the idea, that what in all his experience are immutable forms of life may have once worn another guise. The hypothesis itself is a very old one; it was, as all the world knows, strongly advocated by LAMARCK, and later still by the author of the "Vestiges of the Natural History of the Creation," but neither of these authors were able to suggest even a plausible method according to which Nature might have proceeded in producing suitable varieties, getting rid of intermediate forms, and giving a temporary stability to such as are recognised as species by all observers. Mr. DARWIN has been more successful, though whether completely so or not the future alone can show. We shall proceed to examine his method in another article.

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