Answer:
12-14 october
Explanation:
The probable period of exposure is calculated as follows:
- Know the range of the incubation period
- Start counting back from the days of the first case by subtracting the first number of incubation period range
- Count back the days from the last case by subtracting the last number of incubation period range.
- This will give a range which will be the period of exposure.
From the question,
- Incubation period range 1-15
- Date of first case = october 15
- Therefore, first date of exposure = 15 -1 = 14
- Date of last case = 22
- Therefore, last date of exposure = 27 - 15 = 12
- Thus, the range is 12-14 october which is the probable period of exposure.
Cell-wall inhibiting antimicrobial drugs be less effective on gram-negative bacteria compared to gram-positive bacteria because the outer membrane of the gram-negative bacteria inhibits penetration of the drug and the peptidoglycan found in gram-positive bacteria is structurally different from that in gram-negative bacteria.
Answer: Option B & C
<u>Explanation:</u>
Antimicrobial drugs are induced into a body to act on that particular selective bacterium which causes disease. When antimicrobial drugs are injected they act efficiently on the gram positive bacteria inhibiting the proliferation of the cells by acting on the cell wall so that cell multiplication doesn’t happen.
On the other hand it is hard to act on the gram-negative bacteria as it has a cell membrane that inhibits drug penetration into it. Both cell walls contain peptidoglycan but in the gram-positive is more assembled and layered while in the gram-negative it is just a thin layer. As gram-positive is thick layered it provides place for another molecule to attach to it but the thin layer in gram-negative inhibits it.
Answer:
When water is added to a graduated cylinder, having a surface where the sides of the water look higher than the center means that the curved surface is a concave meniscus which has formed because of surface tension (Choice C).
Explanation:
A meniscus is simply the curvature that the surface of a liquid acquires when it is in a container, such as a graduated cylinder. It is concave when there is attraction between molecules -water and glass- or it can be convex when both surfaces are repelled.
<u>Water is a polar molecule</u>, with the capacity to adhere to the surfaces it comes into contact with. This characteristic causes it to form a concave meniscus, as the outermost molecules adhere to the glass surface, while the surface tension of the water attracts the molecules from the centre downwards, causing the concavity.
Learn more:
Measuring with a graduated cylinder brainly.com/question/4070509
