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Anna35 [415]
2 years ago
9

A scientist discovered a new antibiotic and wanted to know if it would be effective against group A Streptococcus bacteria. He d

esigned a test experiment in a lab with ten different cultures of the bacteria. He introduced the antibiotic into five of the cultures, leaving the other five to grow without it. He recorded observations every three hours for a week.
What is the independent variable in this experiment?
A.
the total number of bacteria cultures
B.
the presence of the new antibiotic
C.
the reaction of the bacteria to the antibiotic
D.
the presence of the Streptococcus bacteria
Biology
1 answer:
Tom [10]2 years ago
6 0
An experiment is a process where the a scientist tests and draws their evidence and data from. Hence, this process is where the hypothesis be supported or negated.

Variables are traits, factors, or characteristics that either manipulated or measured being the subject to become the data.
The independent variable is B. 
<span>the presence of the new antibiotic</span>
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Answer:

See the answer below

Explanation:

Since bacteria are prokaryotes, they have no nucleus and membrane-bound organelles. The outside of a bacterial cell is protected by a structure called a capsule. The cell wall provides a rigid structure that gives the cell its shape. The cell membrane helps to transport ions, nutrients, and waste. The plasmids allow DNA to be transferred from one bacterium to another.

<em>The bacteria are microscopic organisms that are generally classified as prokaryotes. The prokaryotes lack nucleus and other membrane-bound organelles, unlike the eukaryotes. The bacteria cells are enclosed in a protective structure known as the capsule. Immediately after the capsule is the cell wall whose components vary depending on whether the bacteria is Gram-positive or negative. </em>

<em>Towards the innermost part of the cell, after the cell wall is the cell membrane. It acts as a channel for the transport of materials in and out of the cell. Some bacteria cells have short, circular, extrachromosomal DNA known as plasmids which can be transferred from one cell to another.</em>

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2 years ago
Living organisms must acquire energy from their environment. Examples of adaptations that help organisms acquire this energy inc
krek1111 [17]

Answer:

The correct answers are Option A and B

Explanation:

A. The dark, heat-absorbing coloration of a reptile.

B. The fangs and claws of a lion

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There are several properties of water that make Earth a suitable environment for life, including water's high boiling point and
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Vitek1552 [10]

Answer and Explanation: The farmer has a pure-breeding line of tomato means the farmer has a tomato with genotype FFrrtt while the other line of tomato has genotype ffRRTT.

The cross between these lines gives a F1 generation of heterozygous full, red and axial or FfRrTt.

With an individual of F1 crosses with another individual of F1, the Punnet Square will be:

FfRrTt x FfRrTt

1) Dividing each characteristics, for simplicity:

          F         f

F       FF       Ff

f        Ff        ff

          R       r

R       RR     Rr

r        Rr      rr

         T      t

T       TT   Tt

t        Tt     tt

Analysing Punnett squares, we notice the line wanted (ffrrTT) will be produced, when an individual of F1 generation cross with another individual with the same generation.

       

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In physics a players natural resistance to an unbalanced force is called?
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Answer:

if a players natural resistance to an unbalanced force is called unbalanced force

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