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(Solved) - (a) Calculate the number of cells in a hummingbird assuming... - (1 Answer)

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(Solved) – (a) Calculate the number of cells in a hummingbird assuming… – (1 Answer)

Two sources, S1 and S2, emit harmonic waves in phases with the same amplitude, wavelength and frequency.At a point P, which is at a distance x1 from the source S1 and a distance x2 from the sourceS2, the equations of the two waves areShow that the…

Solved: (a) Calculate the number of cells in... |

Solved: (a) Calculate the number of cells in… | – Chapter: CH1 CH2 CH3 CH4 CH5 CH6 CH7 CH8 CH9 CH10 CH11 CH12 CH13 CH14 CH15 CH16 CH17 CH18 CH19 CH20 CH21 CH22 CH23 assuming the mass of an average cell is ten times the mass of a bacterium. (b) Making the same assumption, how many cells are there in a human?You estimate the mass to be between 10 and 20 grams from how heavy it feels in your hand, but this is not a Other times we know a theoretical value, which is calculated from basic principles, and this Suppose you time the period of oscillation of a pendulum using a digital instrument (that you assume…Gravitational Mass: It is the mass of the material body, which determines the gravitational pull acting upon it. According to the principle of equivalence If the mass of the sun were ten times smaller and gravitational constant G were ten times larger in magnitude. sun Then, (a) walking on ground would…

Measurements and Error Analysis – In terms of cell type, the body contains hundreds of different types of cells, but notably, the largest number Pie charts of typical human body composition by percent of mass, and by percent of atomic composition Not all elements which are found in the human body in trace quantities play a role in life.10-3 ■ deviation of actual vapor power cycles from idealized ones. Assume the steam is reheated to the inlet temperature. FIGURE 10-14 The first part of the heat-addition process in the boiler takes place at relatively low temperatures.Ongoing mass vaccination deployments are "highly-likely to further enhance 'adaptive' immune escape as none of the current vaccines will prevent replication/transmission of viral variants". As such, "The more we use these vaccines for immunizing people in the midst of a pandemic, the more infectious…

Measurements and Error Analysis

NCERT Exemplar Class 11 Physics Chapter 7 Gravitation – Learn CBSE – The mass of a hummingbird is of the order of 10 ?2 kg and that of a bacterium is 10 ?15 kg. cells (b) Making the same assumption, how many cells are there in a human if his…Average atomic mass is calculated by getting the summation of the product of the mass of each isotope multiplied by its own natural abundance( which is The interesting thing is that we find that the mass of an atom is not equal to the sum of its parts. You assume that the F-19 atom should have…Mass of a hummingbird is 10^-2 kg Mass of a bacterium is 10^-15 kg Hint: Find the mass of a cell first. number of cells = mass of a human/mass of a cell. Assuming one nerve impulse must end before another can begin, what is the maximum firing rate of a nerve in impulses per second?

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Dose (biochemistry) | Wikipedia audio article – A dose is a measured quantity of a medicine,
nutrient, or pathogen which is delivered as a unit.
The greater the quantity delivered, the larger
the dose. Doses are most commonly measured for compounds
in medicine. The term is usually applied to the quantity
of a drug or other agent administered for therapeutic purposes, but may be used to describe
any case where a substance is introduced to the body. In nutrition, the term is usually applied
to how much of a specific nutrient is in a person's diet or in a particular food, meal,
or dietary supplement. For bacterial or viral agents, dose typically
refers to the amount of the pathogen required to infect a host. For information on dosage of toxic substances,
see Toxicology. For information on excessive intake of pharmaceutical
agents, see Drug overdose. == Factors affecting dose ==
A ‘dose’ of any chemical or biological agent (active ingredient) has several factors
which are critical to its effectiveness. The first is concentration, that is, how much
of the agent is being administered to the body at once. Another factor is the duration of exposure. Some drugs or supplements have a slow-release
feature in which portions of the medication are metabolized at different times, which
changes the impacts the active ingredients have on the body. Some substances are meant to be taken in small
doses over large periods of time to maintain a constant level in the body, while others
are meant to have a large impact once and be expelled from the body after its work is
done. It’s entirely dependent on the function
of the drug or supplement. The route of administration is important as
well. Whether a drug is ingested orally, injected
into a muscle or vein, absorbed through a mucus membrane, or any of the other types
of administration routes, affects how quickly the substance will be metabolized by the body
and thus effects the concentration of the active ingredient(s). Dose-response curves may illustrate the relationship
of these metabolic effects. == Medicines == === Over-the-counter medications ===
In over-the-counter medicines, dosage is based on age. Typically, different doses are recommended
for children 6 years and under, children aged 6 to 12 years, and persons 12 years and older,
but outside of those ranges the guidance is slim. This can lead to serial under or overdosing,
as smaller people take more than they should and larger people take less. Over-the-counter medications are typically
accompanied by a set of instructions directing the patient to take a certain small dose,
followed by another small dose if their symptoms don’t subside. Under-dosing is a common problem in pharmacy,
as predicting an average dose that is effective for all individuals is extremely challenging
because body weight and size impacts how the dose acts within the body. === Prescription drugs ===
Prescription drug dosage is based typically on body weight. Drugs come with a recommended dose in milligrams
or micrograms per kilogram of body weight, and that is used in conjunction with the patient's
body weight to determine a safe dosage. In single dosage scenarios, the patient's
body weight and the drug's recommended dose per kilogram are used to determine a safe
one-time dose. In drugs where multiple doses of treatment
are needed in a day, the physician must take into account information regarding the total
amount of the drug which is safe to use in one day, and how that should be broken up
into intervals for the most effective treatment for the patient. Medication underdosing occurs commonly when
physicians write prescriptions for a dosage that is correct for a certain time, but fails
to increase the dosage as the patient needs (i.e. weight based dosing in children, or
increasing dosages of chemotherapy drugs if a patient’s condition worsens). === Medical cannabis ===
Medical cannabis is used to treat the symptoms of a wide variety of diseases and conditions. The dose of cannabis depends on the individual,
the condition being treated, and the ratio of cannabidiol (CBD) to tetrahydrocannabinol
(THC) in the cannabis. CBD is a chemical component of cannabis that
is not intoxicating and used to treat conditions like epilepsy and other neuropsychiatric disorders. THC is a chemical component of cannabis that
is psychoactive. It has been used to treat nausea and discomfort
in cancer patients receiving chemotherapy treatment. For anxiety, depression, and other mental
health ailments, a CBD to THC ratio of 10 to 1 is recommended. For cancer and neurological conditions, a
CBD to THC ratio of 1 to 1 is recommended. The correct dosage for a patient is dependent
on their individual reaction to both chemicals, and therefore the dosing must be continually
adjusted once treatment is initiated to find the right balance. There is limited consensus throughout the
scientific community regarding the effectiveness of medicinal cannabis. === Cancer ===
Calculating drug dosages for treatment for more serious diseases like cancer is commonly
done through measuring the Body Surface Area of the patient. There are approximately 25 different formulae
for measuring a patient’s body surface area, none of them exact. See also Body surface area. Because of the variety of methods to select
when determining a patient’s body surface area, studies show that choosing the best
method for an individual patient is a difficult task, and often a patient receives too much
or too little medication based on physical anomalies that don’t necessarily fit perfectly
with the portfolio of the body surface area.Because these methods are inexact, they are typically
adjusted by what’s known as ‘toxicity-adjusting dosing’ where physicians monitor the immune
suppression and adjust dosing according to the results to minimize either under and overdosing. This trial-and-error method has been shown
to be risky to the patient and costly to healthcare companies, as well as inefficient, because
of the constant monitoring that is required. Research is occurring constantly to develop
new dosing methods that are more accurate and safe for the consumer. === Ongoing research ===
Another approach that’s been investigated recently is dosing on a molecular level, either
through conventional delivery systems, nanoparticle delivery, light-triggered delivery, or other
less known/used methods. By combining these drugs with a system that
detects the concentration of drug particles in the blood, proper dosing could be achieved
for each individual patient. Research in this field was initiated with
monitoring of small-molecule cocaine levels in undiluted blood serum with electrochemical
aptamer-based sensing. DNA aptamers, which are peptides that have
with specific target molecules that they search for, fold in response to the molecule when
they find it, and this technology was used in a microfluidic detection system to create
an electrochemical signal that physicians can read. Researchers tested it on cocaine detection
and found that it successfully found trace amounts of cocaine in blood.This research
was expanded upon and led to the creation of a product called MEDIC (microfluidic electrochemical
detector for in vivo continuous monitoring) developed by faculty at the University of
California at Santa Barbara. MEDIC is an instrument that can continuously
determine the concentrations of different molecules in the blood. The blood doesn’t have to be mixed with
anything prior to testing to create a ‘serum’ as the first device did. MEDIC can detect a wide variety of drug molecules
and biomarkers. In trials, early models of the device failed
after about half an hour because the proteins in whole blood clung to the sensors and clogged
the components. This problem was solved via a second chamber
that allowed a liquid buffer to flow over the sensors with the blood, without mixing
or disturbing the blood, so the results remained unchanged. The device is still in clinical trials and
actual implementation in medicine is likely years away, however in the interim, its creators
estimate that it could also be used in the pharmaceutical industry to allow for better
testing in Phase 3 clinical trials. == Vaccines ==
Vaccinations (see Vaccine) are typically dosed in milliliters because most are administered
as liquids. Each individual vaccine comes with constraints
regarding at what age they should be administered, how many doses must be given, and over what
period of time. There are 15 vaccines that the Center for
Disease Control and Prevention recommends every person (in America) receive between
birth and 18 years of age to protect themselves against various infectious agents that can
cause lifelong problems. Most vaccines require multiple doses for full
immunity, given in recommended intervals depending on the vaccine. There are several typical vaccination routes:
Intramuscular injection: the needle is inserted perpendicular to the skin into the muscle,
beneath the skin and (subcutaneous) tissues that rest on top. Subcutaneous injection: the needle is inserted
at a 45 degree angle into the (subcutaneous) tissue between the outer layer of the skin
and the muscle. Nasal: the vaccine is sprayed into the nose
and absorbed through the nasal passage. Oral: the vaccine is swallowed and ingested. == Nutrition ==
For healthy humans, experts recommend daily intake quantities of certain vitamins and
minerals. The Food and Nutrition Board, Institute of
Medicine, and National Academy of Sciences sets a recommended Dietary Reference Intake
(DRI) in several forms: Recommended Dietary Allowance (RDA): average
daily intake which adequately meets the nutrient requirements of 97-98% of healthy individuals. Adequate Intake (AI): established when the
evidence gathered for an RDA is inconclusive, An AI is assumed to recommend a daily amount
to meet nutritional adequacy. Tolerable Upper Intake Level (UL): maximum
amount of a nutrient which can be consumed without causing adverse impacts to an individual’s
health.DRIs are established for elements, vitamins, and macronutrients. Common elemental and vitamin dosages are milligrams
per day (mg/d) or micrograms per day (μg/d). Common macronutrient dosages are in grams
per day (g/d). Dosages for all three are established by both
gender and age. Individuals take vitamin and mineral supplements
to promote healthier lifestyles and prevent development of chronic diseases. There is no conclusive evidence linking continued
vitamin and mineral supplement intake with longevity of life. == Infectious dose ==
The infectious dose of a pathogen is the number of cells required to infect the host. All pathogens have an infectious dose typically
given in number of cells. The infectious dose varies by organism and
can be dependent on the specific type of strain. Some pathogens can infect a host with only
a few cells, while others require millions or billions. Examples of infectious doses, ranked loosely
in increasing order: Enterohemorrhagic E. coli (causes hemorrhaging
of the intestines): 10 bacteria cells Hepatitis A: 10-100 virus particles
Norovirus (commonly called ‘a stomach bug’): 10-100 virus particles
Rotavirus (severe diarrhea, can be fatal): 10-100 virus particles
Shigella (shigellosis): 500 bacteria cells Streptococcus pyogenes (Group A strep throat):
1000 bacteria cells Salmonella: varies by strain, 100-1 billion
bacteria cells Vibrio cholerae (Cholera): 1000-100,000,000
bacteria cellsTypically, stomach acids can kill bacteria below the infectious dosing
rage for a given pathogen and keep the host from feeling symptoms or falling ill. Complexes constructed by fat can protect infectious
agents from stomach acid, making fatty foods more likely to contain pathogens that successfully
infect the host. For individuals with low or reduced stomach
acid concentrations, in infectious dosage for a pathogen will be lower than normal.Rather
than being administered by a physician or individual, infectious dosages are transmitted
to a person from other persons or the environment, are generally accidental, and result in adverse
side effects until the pathogen is defeated by the individual's immune system or flushed
out of the individual's system by excretory processes .