The foods must be cooled to below 4 °C
PCR (polymerase chain reaction) is a relatively new advance (1980's) but it has a great impact in our lives. Specifically, in forensic science, PCR is useful in many sorts of crimes . Up until the PCR method, in order to identify a person forensic scientists would use fingerprints or some other ambiguous methods like teeth marks etc. But now, with PCR, we can compare the genetic material found on a crime scene and compare it with a suspect's genetic material, definitively concluding whether they are the same person or not. The way this works is that we collect a sample from the crime scene with DNA and then PCR amplifies the quantity of DNA in that sample. One of the apparent advantages of this method is that PCR works with even a very small sample, often not even a single cell is required. This makes crime scenes full of information. Hence, succinctly, PCR has helped modern forensic science in that:
1) its results are more definitve than traditional identification methods and subject to less ambiguity
2) it is relatively fast
3) new pieces of evidence can be of value (like some hair cells) and identify the crominal in cases that in older times would be impossible to solve.
Pollen....because cones are absent in angiosperms.....flowers are absent in gymno....and seeds are also absent in gymno sperm........so and is pollen !
Drinking salt water is harmful because it messes up the salt concentration in each of your red blood cells. It over loads the salt in it and causes the cell to swell up and burst due to it trying to let in more water to balance the salt concentration out.
Answer:
b. pass through pores in the capillary endothelium
Explanation:
The fenestrated capillaries and sinusoids have pores in their endothelium. These pores or the intracellular clefts vary in size between the fenestrated capillaries and sinusoids. Sinusoids have larger intracellular clefts. The pores serve as a passage for the movement of water-soluble substances, proteins and other substances that cannot cross the hydrophobic interior of the cell membranes.
Water-soluble hormones also cannot pass through the capillary walls. Therefore, these hormones pass through the pore or the fenestrations present in the endothelium of capillaries.
