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Mashutka [201]
3 years ago
8

A student placed a disk of filter paper in each of the following solutions: disinfectant 1, disinfectant 2, disinfectant 3, and

distilled water. While the four disks were soaking in their respective solutions, she streaked a sterile nutrient agar dish with a culture of E. coli bacteria. Then, she placed each disk carefully onto the nutrient agar dish, placed the lid on the dish, taped it shut, and incubated the dish at 37°C for several days. The diagram shows how the nutrient agar dish looked on Day 1 and Day 4. The shaded portion of the plate on day 4 indicates the bacterial growth. What is the control in the experiment? A. Disk soaked in disinfectant 1 B. Disk soaked in disinfectant 3 C. Disk soaked in distilled water D. Disk soaked in disinfectant 2
Biology
1 answer:
Sergeeva-Olga [200]3 years ago
5 0

This whole is experiment is called the Kirby Bauer disk diffusion method. It is testing the susceptibility of microorganisms to disinfectants to see which disinfectant works the best against killing the bacteria.
By asking which is the control it would mean the experiment is unaffected and kept the same.

That means the answer is C because water does not affect the bacteria

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Answer:

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Explanation:

Flatworms, roundworms, and segmented worms are all invertebrates. Some species of each type of worm are free-living, meaning they are not dependent on another organism.Some are parasitic.

Flatworms belong to phylum Platyhelminthes. They do not have a coelom, respiratory system or a circulatory system.Tapeworms flukes are examples of flatworms.

Roundworms are part of the phylum Nematoda. They are bilaterally symmetrical invertebrates.They have a psuedocoelom. Ascaris lumbricodes is the most common human parasite.

Segmented worms are the most complex animals of these three invertebrates. They are placed in Annelida. Segmented worms have a true coelom, a circulatory system and a digestive system.An earthworm is a segmented worm.

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3 years ago
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MatroZZZ [7]

Answer:

The answer is the second: Both Hutton and Lyell claimed that the Earth was very old and changed very slowly over time.

Explanation:

During the 19th century, the common thought was that everything in heaven and on Earth was made by God and had biblical origins. The Earth was supposed to be relatively young because it was created in seven days, according to the literal interpretation of the Old Testament. Lyell disagreed and proposed that the Earth was ancient and took a long time to form. Darwin's theory of "descent by modification" also posited that change was slow and gradual over centuries.

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Question 1 Life would cease to exist without energy from the sun or some other source.
malfutka [58]

Answer:

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Q3) Physiological response

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Question 6 Unsaved
muminat
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Answer:

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Diffusion does not require energy

6 0
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