The ability for an individual to survive and reproduce in its for specific environment. Any inherited characteristics that increases an organisms chance of survival. Individuals that are better suited to their environment, survive and reproduce most successfully.
A rapid lateral flow immunoassay is presented that uses carboxyl-modified superparamagnetic nanoparticles as labels that can be quantified by highly sensitive multi-channel electronic readers. The approach is generic in that it is likely to be applicable to numerous small molecules. The method permits both single- and multiplex assays at a point-of-need without sample pretreatment. It is user-friendly and offers attractive characteristics demonstrated here for detection of morphine, fentanyl and methamphetamine in . The competitive immunoassay uses commercially available reagents that do not require special permissions. After migration of sample, the lateral flow test strips are subjected to an alternating magnetic field at two frequencies. The response from the nanolabels is readout at a combinatorial frequency from the entire volume of a porous immunochromatographic membrane by the magnetic particle quantification technique.
application to the determination of drugs of abuse.
Estimating the detection time of a drug in urine is complex because of many different influencing factors and the lack of experimental data. Detection times vary depending on dose and route of administration, metabolism and characteristics of the screening and confirmation assays. Using a cut-off value of 1000 ng/mL, urinary samples can be positive for amphetamine for up to 5 days after intake of the drug.
Answer:
This question is asking to identify the variable in the experimental statement.
The eye chart is the CONTROL VARIABLE
Explanation:
An experiment consists of several variables to look out for in order to achieve any significant result. These variables are independent variables, dependent variables and control variables. Although independent and dependent variables are the major experimental variables, but control variables are also important.
A control variable is the variable that remains constant or unchanged throughout the experiment. Any change to the control variable will affect the dependent and independent variables. In this question, the eye chart is the CONTROL VARIABLE because it remains constant or unchanged. The same eye chart is used for the experiment.
N.B: The distance to the eye chart is the independent variable while the number of letters visible on the line is the dependent variable. Hence, changing the eye chart (control variable) will affect the distance and the number of letters visible.
Reference point .................................
<span>A biologist can infer from a population that is uniformly distributed through its habitat that it has reached it's carrying capacity. If resources were unevenly distributed through the environment, you would not see a uniform distribution of the population itself.</span>
