Scientists know that a mutation - or alteration - in a particular gene's DNA may contribute to a certain disease. However, it can be very difficult to develop a test to detect these mutations, because most large genes have many regions where mutations can occur. For example, researchers believe that mutations in the genes BRCA1 and BRCA2 cause as many as 60 percent of all cases of hereditary breast and ovarian cancers. But there is not one specific mutation responsible for all of these cases. Researchers have already discovered over 800 different mutations in BRCA1 alone.
The DNA microarray is a tool used to determine whether the DNA from a particular individual contains a mutation in genes like BRCA1and BRCA2. The chip consists of a small glass plate encased in plastic. Some companies manufacture microarrays using methods similar to those used to make computer microchips. On the surface, each chip contains thousands of short, synthetic, single-stranded DNA sequences, which together add up to the normal gene in question, and to variants (mutations) of that gene that have been found in the human population.
Answer:
To maintain body homeostasis
Explanation:
The endocrine system consists of the endocrine glands that release hormones directly int the blood. Those hormones bind to their receptors on the target cells and thus regulate their function. The major glands are:
pineal gland-releases melatonin, controls sleep cycle
pituitary gland-control growth, blood pressure, thyroid glands and metabolism etc.
pancreas-secretes insulin and glucagon, control of blood sugar levels
ovaries, testes-reproductive role (release female and male hormones)
thyroid gland-controls metabolism and protein synthesis
parathyroid gland-controls Ca levels
hypothalamus-connects nervous and endocrine systems, controls other glands
adrenal glands-release adrenalin and steroid hormones.
Answer:
I think the correct qnswer for this question is 50% but it is not given in the option so the correct answer is 30 %
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Answer:
The most diverse group of seedless vascular plants are <u>the ferns .</u>
Explanation:
Ferns -
Ferns are the most advance seedless vascular plants and is the most diverse group . Ferns have branching roots and large leaves . But the whisk ferns , have lack of roots and leaves due to evolutionary reduction . In the process of evolutionary reduction , the natural selection reduces the size of the structure which no longer favors the particular environment . Hence , Photosynthesis in whisk ferns takes place in their green stem .
Answer:
Your answer should be A on the first two, and b on the third!!
Explanation:
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