Answer:
(a) number of strands (n) = time (t) ÷ proportionality constant (k)
(b) The time needed for the bacterial to double its initial size is 3.36 hours.
Explanation:
(a) Let the rate (time) be represented by t and the amount (number) of strands of bacteria be represented by n
t is proportional to n, therefore, t = kn (k is the proportionality constant)
Since t = kn, then, n = t/k
(b) Initial amount of strands = 300
Amount of strands after 2 hours = 300 + (300 × 20/100) = 300 + 60 = 360
k = t/n = 2/360 = 0.0056 hour/strand
Double of the initial size is 600 (300×2 = 600)
Time (t) needed for the bacterial to double its initial size = kn = 0.0056×600 = 3.36 hours
Answer:
The bell of the stethoscope is used during auscultation to listen for low pitched sounds typical of a heart murmur.
Explanation:
Auscultation is a diagnostic test that listens to sounds from the heart, lungs, bowels, the circulatory system and other parts of the human body.
The stethoscope is an instrument that is designed for auscultation.
The diaphragm of the stethoscope listens for high pitched sounds typical of the bowels, a normal heart, and breathing.
The bell of the stethoscope listens for low pitched sounds typical of a heart murmur.
Answer: B. The bacteria must adjust to the nutrient content in the new medium, synthesizing necessary amino acids, growth factors, and enzymes.
Explanation: The lag phase is a time for adjustement to new environments, in this case new mediums. In that phase, bacteria sense the available nutrients to synthesize those required and grow as preparing for division, metabolizing to produce energy, making proteins, fatty acids, etc.
Answer:
Cyanide is considered a specific neurotoxin and is often associated with high levels of cellular calcium and inhibition of antioxidants, leading to the formation of reactive oxygen species (ROS) and consequent lipid peroxidation. But cyanide toxicity is mainly due to the iron (Fe (III) or Fe3 +) iron binding of the mitochondrial cytochrome oxidase enzyme of the electron transport chain. This enzyme mediates the transfer of electrons to molecular oxygen
. By blocking this enzyme, the cell is unable to use oxygen and uses an anaerobic metabolism reducing pyruvate to lactic acid (lactic fermentation), which results in tissue anoxia and the rapid development of lactic acidosis. There is also a change in cell metabolism as there is a depletion in energy production. So it causes cell death. This would be the mechanism to kill cancer cells. Although, cyanide cant be use to treat cancer because it kills all the cells (leading to death) and not only the cancer cells.
Explanation:
Some researchers founded that cyanide poison may have the role of being a powerful cancer fighter. It believes that they can relate the enzyme to cancer by looking for antibodies that can recognize a protein found only in certain cancers. The method would produce an agent that could potentially kill cancer cells and leave undamaged tissue healthy.
As for the deadly nature of cyanide, scientists say the amount produced by this technique iwould be sufficient only to kill the cancer target cell by a combined enzyme and antibody molecule. And a natural enzyme produced in the human liver could detoxify any cyanide that could escape the tumor. Although, cyanide is a drug that, even if ingest a small amount, could lead to death. Some studies are going on, but until now, theres no safety of taking cyanide to treat cancer cells.
