<span>Thylakoids contain the components needed for photosynthesis. They are the flattened sacs in the chloroplast where the membranes where the light reactions take place for photosynthesis, the process by which light energy is converted into chemical energy.</span>
I think the answer is compound.
Complete question
- It has to be E. coli because it is positive for gapA
- It can't be Salmonella, because it is negative for the invA marker but still makes people sick
- It has to be used because it is positive for the apeE marker
Answer:
<u>1. It can't be Salmonella, because it is negative for the invA marker but still makes people sick </u>
- A combination of positive results from the multiplex PCR inva, apee and gapa is used to definitively identify Salmonella.
- Pathogenic, or disease causing Salmonella is definitely not present, as inva is required for it to be pathogenic. The test did not detect the inva sequence, thus it is truly negative for this particular pathogen.
<u>2. It has to be E. coli because it is positive for gapA </u>
- E. coli may be present, as gapa was detected- a presumptive positive. However, this may need to be definitively determined through further methods of sample analysis, such as 2D-gel electrophoresis.
- apee may belong to another type of bacteria present within the initial sample, or there may be sample contamination
Explanation:
Polymerase chain reactions, PCRs are a form of nucleic acid amplification testing NAAT that exploit the mechanism of transcription by using a thermostable DNA polymerase. These require a sample of genetic material such as RNA or DNA; specific regions of the gene sequence are targeted for replication by primers. In the presence of these specific gene sequences, the primers make billions of copies of the sequences.
However, if these gene sequences are absent, the primers are not capable of identifying and amplifying the sequence. This reaction is highly specific. Positives obtained have a high chance of being true positives and negatives have a high chance of being true negatives
.
Pathogens or infectious agents that are capable of causing disease i.e. making people sick. Both E. coli and Salmonella are genuses of enteric bacteria capable of causing disease via fecal contamination. Common symptoms include
- abdominal cramps
- vomiting
- fever
- diarrhea
This test would include primers for the detection of each sequence: gapa, apee, inva. Salmonella's inva was not detected, thus it is not present.
Further steps may include a 2 D gel electrophoresis- here an electrical current is utilized to separate bands of DNA within the sample. This should correspond with an expected DNA size in base pairs or bp for E.coli- this should be determined by running the sample in the gel with a positive control, containing genetic material for E coli, and a negative control, of purified water to determine contamination.
<span>The role of the negative feedback loop is,
that the output is being reduced so that the body can maintain homeostasis.
The negative feedback loop is a homeostatic control mechanism through which levels of hormones are maintained within a narrow range by feeding the product back to decrease its production.</span>
Answer:
1. They provide home and shelter for millions of species of marine organisms.
2. They play a role as nutrient recyclers and in carbon and nitrogen fixation.
3. They are vital in the marine food chain as they are the main source of essential nutrients.
Explanation:
Cnidarians are extremely ecologically important organisms that play a significant role in the animal kingdom and nature.
For instance, coral reefs, which are built by hundreds to thousands of cnidarians, provide home and shelter for millions of species of marine organisms, from small crustaceans to large fish such as sharks. Furthermore, they play a role as nutrient recyclers and in carbon and nitrogen fixation. In addition, they are vital in the marine food chain as they are the main source of essential nutrients such as nitrogen.
Today, these organisms are threatened due to human activities and anthropogenic climate change, so it is fundamental to develop better strategies to protect and restore them.