What is the structure of a virus?

 

 

The structure of a virus consists of the following main components:

1. Genetic Material (Genome) – A virus contains either DNA or RNA, which carries the genetic instructions needed for replication. This genetic material can be single-stranded (ss) or double-stranded (ds) and either linear or circular.

2. Capsid (Protein Coat) – This is a protective shell made of protein subunits called capsomeres. The capsid encloses the genetic material and provides structure to the virus. Capsids can have different shapes:

   • Helical (e.g., Tobacco mosaic virus)

   • Icosahedral (e.g., Adenovirus)

   • Complex (e.g., Bacteriophages)

3. Envelope (Lipid Membrane) (Optional) – Some viruses have an outer lipid bilayer derived from the host cell membrane, known as the viral envelope. It contains viral proteins, including spike proteins, which help the virus attach to host cells. Examples of enveloped viruses include influenza and HIV.

4. Surface Proteins (Spike Proteins or Glycoproteins) – These proteins protrude from the capsid or envelope and are critical for viral attachment and entry into host cells. For example, coronaviruses (e.g., SARS-CoV-2) use spike proteins to bind to host cell receptors.

5. Enzymes (In Some Viruses) – Some viruses carry enzymes to assist in replication. For example:

   • Reverse transcriptase (in retroviruses like HIV) converts RNA into DNA.

   • RNA-dependent RNA polymerase (in RNA viruses) helps replicate their genome.

Summary

Viruses are acellular entities with a simple structure, consisting of genetic material, a capsid, and sometimes an envelope and specialized enzymes. They rely entirely on a host cell for replication.

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Microbiology

Microbiology is the branch of science that studies microorganisms, including bacteria, viruses, fungi, protozoa, and algae. It explores their structure, function, genetics, ecology, and their roles in health, disease, and the environment. Microbiology is essential in fields like medicine, biotechnology, agriculture, and food science, as it helps develop antibiotics, vaccines, and biotechnological applications. It also investigates microbial interactions with humans, animals, plants, and ecosystems, contributing to advancements in public health, industrial processes, and environmental sustainability.

Microbiology has several branches, each focusing on different aspects of microorganisms and their interactions with humans, animals, plants, and the environment. The main branches of microbiology include:

1. Bacteriology

This branch focuses on the study of bacteria, including their structure, function, classification, and role in diseases. Bacteriology is essential in medical research, antibiotic development, and industrial applications like fermentation.

2. Virology

Virology is the study of viruses, their structure, genetics, replication, and how they cause diseases. It plays a crucial role in vaccine development, antiviral drugs, and understanding viral epidemics like COVID-19.

3. Mycology

Mycology deals with fungi, including yeasts, molds, and mushrooms. It studies their role in decomposition, food production (e.g., cheese and bread), and diseases like fungal infections in humans and plants.

4. Parasitology

This branch studies parasites, including protozoa, helminths (worms), and arthropods that cause diseases in humans, animals, and plants. Parasitology helps in controlling infections like malaria and intestinal worms.

5. Phycology (Algology)

Phycology is the study of algae, which are photosynthetic microorganisms. Algae play a significant role in aquatic ecosystems, oxygen production, and biofuel research.

6. Immunology

Immunology focuses on the immune system and how it defends against microorganisms. It is vital in vaccine development, allergy research, and understanding autoimmune diseases.

7. Environmental Microbiology

This field studies microorganisms in natural environments like soil, water, and air. It includes microbial ecology, bioremediation (using microbes to clean pollution), and wastewater treatment.

8. Industrial Microbiology

Industrial microbiology applies microorganisms in industrial processes, such as the production of antibiotics, enzymes, vaccines, and fermented products like beer, yogurt, and cheese.

9. Agricultural Microbiology

This branch studies microbes in agriculture, including their role in soil fertility, plant growth, and disease prevention. It includes nitrogen-fixing bacteria and biopesticides.

10. Food Microbiology

Food microbiology examines microorganisms in food production and spoilage. It ensures food safety by studying pathogens, fermentation, and food preservation techniques.

11. Medical Microbiology

Medical microbiology focuses on disease-causing microorganisms and their diagnosis, treatment, and prevention. It is crucial in developing antibiotics, vaccines, and diagnostic techniques.

12. Molecular Microbiology

This branch studies microorganisms at the molecular level, including their genetics, gene expression, and interactions with host cells. It plays a key role in genetic engineering and biotechnology.

13. Space Microbiology

Space microbiology studies how microorganisms behave in space environments, including their survival in extreme conditions and their impact on space missions.

14. Pharmaceutical Microbiology

This branch ensures the sterility and safety of pharmaceutical products by studying microbial contamination in drug manufacturing and production.

Each branch of microbiology contributes to different scientific and practical applications, making it a vital field in medicine, industry, agriculture, and environmental science

Benefits of Microbiology

Microbiology has numerous benefits across different fields, including healthcare, industry, and environmental science. Here are some of its key advantages:

1. Medical Advancements

• Helps in the diagnosis and treatment of infectious diseases.
• Develops antibiotics, vaccines, and antiviral drugs to combat diseases like tuberculosis, COVID-19, and polio.
• Contributes to cancer research and the development of gene therapy.

2. Food Production and Safety

• Plays a vital role in the production of fermented foods like yogurt, cheese, bread, and beer.
• Ensures food safety by detecting and preventing foodborne pathogens.
• Helps in the development of preservatives and probiotics for health benefits.

3. Industrial Applications

• Used in biotechnology to produce medicines, enzymes, and biofuels.
• Helps in the production of antibiotics, vitamins, and insulin through microbial fermentation.
• Supports the development of biodegradable plastics and other eco-friendly products.

4. Environmental Protection

• Microorganisms help in bioremediation, which cleans up oil spills, wastewater, and industrial pollutants.
• Contributes to waste decomposition and recycling of nutrients in ecosystems.
• Assists in water purification and sewage treatment.

5. Agricultural Benefits

• Helps improve soil fertility by fixing nitrogen (Rhizobium bacteria).
• Protects crops from pests using biopesticides and biofertilizers.
• Enhances plant growth through beneficial microbes.

6. Space Exploration

• Studies how microorganisms survive in space, aiding in space travel and planetary exploration.
• Helps in developing life support systems for astronauts.

7. Forensic Science

• Used in criminal investigations to analyze microbial evidence at crime scenes.
• Helps determine the time of death and cause of infections.

Microbiology is essential for improving human health, environmental sustainability, and technological advancements. Its applications continue to grow, making it one of the most impactful scientific fields.

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How to define AIDS and HIV?

HIV and AIDS: Definitions and Differences

HIV (Human Immunodeficiency Virus)

HIV is a virus that attacks the body's immune system, specifically targeting CD4 (T-helper) cells, which help fight infections. Over time, if untreated, HIV weakens the immune system, making the body more vulnerable to infections and diseases.

• Mode of Transmission:

  • Unprotected sexual contact
  • Sharing needles or syringes
  • From mother to child during birth or breastfeeding
  • Blood transfusions with infected blood (rare due to screening)

• Stages of HIV:

  1. Acute HIV Infection (Flu-like symptoms 2-4 weeks after exposure)
  2. Chronic HIV (Asymptomatic Stage) (Virus remains in the body with slow immune damage)
  3. AIDS (Acquired Immunodeficiency Syndrome) (Final stage of HIV if untreated)

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AIDS (Acquired Immunodeficiency Syndrome)

AIDS is the most advanced stage of HIV infection, where the immune system becomes severely damaged. At this stage, the body cannot fight off opportunistic infections and certain cancers.

• Diagnosis:

  • CD4 cell count drops below 200 cells/mm³ (Normal: 500-1,500)
  • Presence of opportunistic infections (e.g., tuberculosis, pneumonia, fungal infections)

• Symptoms of AIDS:

  • Severe weight loss
  • Chronic diarrhea
  • Persistent fever and night sweats
  • Skin rashes and sores
  • Frequent infections

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Key Differences Between HIV and AIDS

Feature	HIV	AIDS
Definition	A virus that weakens the immune system	The final stage of HIV infection
Immune System Impact	Gradual decline in CD4 cells	CD4 count <200 and severe infections
Reversibility	Can be controlled with treatment	Cannot be reversed but can be managed

Treatment and Prevention

• Antiretroviral Therapy (ART):
  • Reduces viral load and prevents progression to AIDS.
  • Allows people with HIV to live healthy lives.
• Prevention Methods:
• Safe sex practices (using condoms, PrEP medication).
• Avoid sharing needles.
• Regular HIV testing and early treatment.

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What is blood collection technique?

Blood collection technique refers to the methods and procedures used to safely and effectively draw blood from a patient for diagnostic testing, transfusions, or research. Proper technique is crucial to ensure accurate test results, minimize patient discomfort, and prevent complications such as infection or hematoma formation.

Types of Blood Collection Techniques

1. Venipuncture (Most Common)

   • Blood is drawn from a vein, usually in the arm (e.g., median cubital vein, cephalic vein).
   • Performed using a syringe, evacuated tube system (vacutainer), or butterfly needle.
   • Commonly used for laboratory tests.

2. Capillary Blood Collection (Fingerstick or Heelstick)

   • Small amounts of blood are collected from capillaries using a lancet.
   • Used for glucose monitoring, newborn screening, and some rapid tests.

3. Arterial Blood Collection

   • Blood is drawn from an artery, typically the radial or femoral artery.
   • Used for blood gas analysis to assess oxygenation and acid-base balance.
   • Requires specialized training due to the risk of complications.

4. Blood Culture Collection

   • Aseptic technique is used to collect blood to detect infections (bacteremia/septicemia).
   • Often requires multiple draws from different sites.

General Steps for Venipuncture

1. Preparation:

   • Verify patient identity and obtain consent.
   • Gather necessary supplies (needles, tubes, alcohol swabs, gloves, tourniquet).
   • Wash hands and wear gloves.

2. Site Selection and Cleansing:

   • Choose an appropriate vein (antecubital fossa is common).
   • Clean the site with an alcohol swab or antiseptic.

3. Blood Collection:

   • Apply a tourniquet above the puncture site.
   • Insert the needle at the correct angle (15-30 degrees).
   • Collect blood into the appropriate tube(s).

4. Post-Procedure:

• Remove the tourniquet before withdrawing the needle.
• Apply gentle pressure with gauze.
• Label the specimen and dispose of sharps safely.
• Ensure patient comfort and monitor for adverse reactions.

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Introduction of Biochemistry

DEFINITION

The term Biochemistry (bios^G = life) was first introduced by a German chemist Carl Neuberg in 1903. Biochemistry may be defined as a science concerned with the chemical nature and chemical behavior of the living matter. It takes into account the studies related to the nature of the chemical constituents of living matter, their transformations in biological systems and the energy changes associated with these transformations. Such studies have been conducted in the plant and animal tissues both. Broadly speaking, biochemistry may thus be treated as a discipline in which biological phenomena are analysed in terms of chemistry. The branch of biochemistry, for the same reason, has been variously named as Biological Chemistry or Chemical Biology. 

In fact, biochemistry originated as an offshoot from human physiology when it was realized that the chemical analysis of urine, blood and other natural fluids can assist in the diagnosis of a particular disease. Hence in its infancy, biochemistry was accordingly known as Chemical Physiology.

But physiology now covers the study of normal functions and phenomena of living beings. And biochemistry is concerned particularly with the chemical aspects of these functions and phenomena. In other words, biochemistry is but one of the many ways of studying physiology. The two may be compared by watching the monkeys in a zoo which means studying the physiology of behaviour. But if the behaviour of animal molecules is FUNDAMENTALS OF BIOCHEMISTRY studied, rather than the whole animals, it would form the study of biochemistry.

Modern biochemistry has two branches, descriptive biochemistry and dynamic biochemistry. 

Descriptive biochemistry is concerned with the qualitative and quantitative characterization of the various cell components and the dynamic biochemistry deals with the elucidation of the nature and the mechanism of the reactions involving these cell components. While the former branch is more a concern of the organic chemist, the latter branch has now become the language of modern biochemistry.

However, as the knowledge of biochemistry is growing speedily, newer disciplines are emerging from the parent biochemistry. Some of the disciplines are enzymology (science of the study of enzymes), endocrinology (science dealing with the endocrine secretions or the hormones), clinical biochemistry, molecular biochemistry etc. Along with these branches certain link specialities have also come up such as agricultural biochemistry, pharmacological biochemistry etc. 

Biochemistry: - It is the branch of natural science which deals with the study of biochemical substance is known as biochemistry.  

Clinical Biochemistry: - It is the branch of medical science which deals with the study of biochemical substance which are directly involved in life is known as clinical biochemistry.

E.g. –Protein, Glucose, lipid etc.

Endocrinology: - As explained above it is advisable to have special area and special instruments for the purpose of hormone analysis.                                                          

Toxicology: - The separate section is to allot for the toxicology especially to assay the drugs like Phenobarbital Phenytoin, Digoxin and so on.

Tumour Markers: - The tumour markers estimation and their value help the clinicians for diagnose the disease of particular organ, treatment and prognosis.

Blood: - Blood is a fluid connective tissue that is pumped by the heart through the vessels (arteries, arterioles, capillaries, venules, and veins) of the cardiovascular system.

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Coronavirus disease (COVID-19): Vaccines

Is there a vaccine for COVID-19? 

Yes, there are now several vaccines that are in use. The first mass vaccination program started in early December 2020 and as of and as of 15 February 2021, 175.3 million vaccine doses have been administered. At least 7 different vaccines (3 platforms) have been administered.

WHO issued an Emergency Use Listing (EULs) for the Pfizer COVID-19 vaccine (BNT162b2) on 31 December 2020. On 15 February 2021, WHO issued EULs for two versions of the AstraZeneca/Oxford COVID-19 vaccine, manufactured by the Serum Institute of India and SKBio. On 12 March 2021, WHO issued a EUL for the COVID-19 vaccine Ad26.COV2.S, developed by Janssen (Johnson & Johnson). WHO is on track to EUL other vaccine products through June. 

The products and progress in regulatory review by WHO is provided by WHO and updated regularly. 

Once vaccines are demonstrated to be safe and efficacious, they must be authorized by national regulators, manufactured to exacting standards, and distributed. WHO is working with partners around the world to help coordinate key steps in this process, including facilitating equitable access to safe and effective COVID-19 vaccines for the billions of people who will need them. 

Will COVID-19 vaccines provide long-term protection?

Because COVID vaccines have only been developed in the past months, it’s too early to know the duration of protection of COVID-19 vaccines. Research is ongoing to answer this question. However, it’s encouraging that available data suggest that most people who recover from COVID-19 develop an immune response that provides at least some period of protection against reinfection – although we’re still learning how strong this protection is, and how long it lasts.

How quickly could COVID-19 vaccines stop the pandemic?

The impact of COVID-19 vaccines on the pandemic will depend on several factors. These include the effectiveness of the vaccines; how quickly they are approved, manufactured, and delivered; the possible development of other variants, and how many people get vaccinated. 

Whilst trials have shown several COVID-19 vaccines to have high levels of efficacy, like all other vaccines, COVID-19 vaccines will not be 100% effective. WHO is working to help ensure that approved vaccines are as effective as possible, so they can have the greatest impact on the pandemic.

What types of COVID-19 vaccines are being developed? How would they work?

Scientists around the world are developing many potential vaccines for COVID-19. These vaccines are all designed to teach the body’s immune system to safely recognize and block the virus that causes COVID-19.

Several different types of potential vaccines for COVID-19 are in development, including:

• Inactivated or weakened virus vaccines, which use a form of the virus that has been inactivated or weakened so it doesn’t cause disease, but still generates an immune response.
• Protein-based vaccines, which use harmless fragments of proteins or protein shells that mimic the COVID-19 virus to safely generate an immune response.
• Viral vector vaccines, which use a safe virus that cannot cause disease but serves as a platform to produce coronavirus proteins to generate an immune response.
• RNA and DNA vaccines, a cutting-edge approach that uses genetically engineered RNA or DNA to generate a protein that itself safely prompts an immune response.

Will other vaccines help protect me from COVID-19?

Currently, there is no evidence that any other vaccines, apart from those specifically designed for the SARS-Cov-2 virus,  will protect against COVID-19.

However, scientists are studying whether some existing vaccines – such as the Bacille Calmette-Guérin (BCG) vaccine, which is used to prevent tuberculosis – are also effective for COVID-19. WHO will evaluate evidence from these studies when available.

What are the benefits of getting vaccinated?

The COVID-19 vaccines produce protection against the disease, as a result of developing an immune response to the SARS-Cov-2 virus.  Developing immunity through vaccination means there is a reduced risk of developing the illness and its consequences. This immunity helps you fight the virus if exposed. Getting vaccinated may also protect people around you because if you are protected from getting infected and from disease, you are less likely to infect someone else. This is particularly important to protect people at increased risk for severe illness from COVID-19, such as healthcare providers, older or elderly adults, and people with other medical conditions.

Who should get the COVID-19 vaccines?

The COVID-19 vaccines are safe for most people 18 years and older, including those with pre-existing conditions of any kind, including auto-immune disorders. These conditions include hypertension, diabetes, asthma, pulmonary, liver, and kidney disease, as well as chronic infections that are stable and controlled. 

If supplies are limited in your area, discuss your situation with your care provider if you:

• Have a compromised immune system
• Are pregnant or nursing your baby
• Have a history of severe allergies, particularly to a vaccine (or any of the ingredients in the vaccine)
• Are severely frail 

Can we stop taking precautions after being vaccinated?

Vaccination protects you from getting seriously ill and dying from COVID-19. For the first fourteen days after getting a vaccination, you do not have significant levels of protection, then it increases gradually. For a single-dose vaccine, immunity will generally occur two weeks after vaccination. For two-dose vaccines, both doses are needed to achieve are required to provide the highest level of best immunity possible. 

While a COVID-19 vaccine will protect you from serious illness and death, we still don’t know the extent to which it keeps you from being infected and passing the virus on to others. To help keep others safe, continue to maintain at least a 1-meter distance from others, cover a cough or sneeze in your elbow, clean your hands frequently and wear a mask, particularly in enclosed, crowded, or poorly ventilated spaces. Always follow guidance from local authorities based on the situation and risk where you live.

Can I have the second dose with a different vaccine than the first dose?

Clinical trials in some countries are looking at whether you can have the first dose from one vaccine and a second dose from a different vaccine. There isn't enough data yet to recommend this type of combination. 

Can the COVID-19 vaccine cause a positive test result for the disease, such as for a PCR or antigen test?

No, the COVID-19 vaccine will not cause a positive test result for a COVID-19 PCR or antigen laboratory test. This is because the tests check for active disease and not whether an individual is immune or not. However, because the COVID-19 vaccine prompts an immune response, it may be possible to test positive in an antibody (serology) test that measures COVID-19 immunity in an individual.

Should I be vaccinated if I have had COVID-19?

Even if you have already had COVID-19, you should be vaccinated when it is offered to you. The protection that someone gains from having COVID-19 will vary from person to person, and we also don’t know how long natural immunity might last. 

Is the vaccine safe for children?

Vaccines are usually tested in adults first, to avoid exposing children who are still developing and growing. COVID-19 has also been a more serious and dangerous disease among older populations. Now that the vaccines have been determined to be safe for adults, they are being studied in children. Once those studies have been completed, we should know more and guidelines will be developed.

In the meantime, make sure children continue to physically distance themselves from others, clean their hands frequently, sneeze and cough into their elbow and wear a mask if age-appropriate.

Do the vaccines protect against variants?

The COVID-19 vaccines are expected to provide at least some protection against new virus variants and are effective at preventing serious illness and death. That’s because these vaccines create a broad immune response, and any virus changes or mutations should not make vaccines completely ineffective. If any of these vaccines become less effective against one or more variants, it will be possible to change the composition of the vaccines to protect against these variants. Data continues to be collected and analyzed on new variants of the COVID-19 virus. 

While we are learning more, we need to do everything possible to stop the spread of the virus in order to prevent mutations that may reduce the efficacy of existing vaccines. This means staying at least 1 meter away from others, covering a cough or sneeze in your elbow, frequently cleaning your hands, wearing a mask, and avoiding poorly ventilated rooms or opening a window. 

How will we know if COVID-19 vaccines are safe?

Ensuring the safety and quality of vaccines is one of WHO’s highest priorities. WHO works closely with national authorities to ensure that global norms and standards are developed and implemented to assess the quality, safety, and efficacy of vaccines. 

The process to develop COVID vaccines is fast-tracked while maintaining the highest standards: Given the urgent need to stop the pandemic, pauses between steps, often needed to secure funding, have been shortened, or eliminated, and in some cases, steps are being carried out in parallel to accelerate the process, wherever that is safe to do. COVID-19 vaccine developers have issued a joint pledge not to seek government approval for their vaccines until they’ve been proven to be safe and effective. 

There are many strict protections in place to help ensure that COVID-19 vaccines are safe. Like all vaccines, COVID-19 vaccines are going through a rigorous, multi-stage testing process, including large (phase III) trials that involve tens of thousands of people. These trials, which include some groups at high risk for COVID-19 (certain groups like pregnant and lactating women were not included in vaccine trials), are specifically designed to identify any common side effects or other safety concerns.

Once a clinical trial shows that a COVID-19 vaccine is safe and effective, a series of independent reviews of the efficacy and safety evidence is required, including regulatory review and approval in the country where the vaccine is manufactured, before WHO considers a vaccine product for EUL or prequalification. EUL or Prequalification verifies to those countries that would want to procure a particular vaccine that there has been an assurance by WHO that the regulatory review process, usually in the country of manufacture, has held up to the highest standards. Part of this process also involves a review of all the safety evidence by the Global Advisory Committee on Vaccine Safety.

An external panel of experts convened by WHO analyzes the results from clinical trials, along with evidence on the disease, age groups affected, risk factors for disease, and other information.  The panel recommends whether and how the vaccines should be used. Officials in individual countries decide whether to approve the vaccines for national use and develop policies for how to use the vaccines in their country based on the WHO recommendations.

After a COVID-19 vaccine is introduced, WHO supports work with vaccine manufacturers, health officials in each country, and other partners to monitor for any safety concerns on an ongoing basis.

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How to find Journal Name, Date, Volume Number, Issue Number, Page Number, DIO Number, Title of Article in Pubmed

 How to find Journal Name, Date, Volume Number, Issue Number, Page Number, DIO Number, Title of Article in Pubmed

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pH AND BUFFERS

PRACTICAL  P^H AND BUFFERS

Introduction: - Practical deals with   pH and buffer solutions. We already know that the pH of the system plays a very vital role in success of many chemical and biochemical reactions. Buffers on the other hand are aqueous solutions that tend to resist any pH change when small amounts of acid or base are added. What is pH? What are buffer solutions? What is the role of buffers? How to prepare buffer solutions? We shall learn about these aspects in this practical.                                                                 

P^H and Buffers: Basic Concepts

In this sections we shall review our knowledge about pH and buffers. We being with pH. 

1.P^H    

You have already studied about pH in your undergraduate years and know what it means. Can you define pH? Write the definition of pH in the space provided. 

Yes mathematically we can define pH as equal the negative log of the hydrogen ion concentration, or pH = -log [H⁺]. In simple terms, Ph is a measure of the acidity or alkalinity of a solution. 

You have studied that the pH scale is a convenient means of expressing the relative acidity or alkalinity of solutions. The pH of the system plays a very vital role in success of many chemical and biochemical reactions. The pH of pure water is 7.0, therefore, the pH of any water sample many given an indication of the types of impurity present in water. 

So now you know what pH means also understand its significance. From your Nutritional chemistry lessons in school and undergraduate years, you should be also determined the pH of solutions using the pH paper. However. pH paper is used when approximate pH values are required. For a more accurate determination of pH, a pH meter is used. We shall learn about the pH meter in section 3.3.

Now let us get to know about buffers. 

2. Buffers and Buffer Solutions

Solutions containing both weak acid and their salts or solutions containing weak hydroxides and their salts are referred to as buffer solutions. They have the capacity of resisting changes in pH when either acid or alkali is added to them. 

Buffers are therefore, aqueous solutions that tend to resist any pH change when small amounts of acid or base are added. A buffer system consists of a weak acid (proton donor) and its conjugate base (proton acceptor) or a weak base and its conjugate acid in comparable concentrations. Because they maintain a constant pH, buffers are good reference solutions. 

A buffer solution can be prepared to have a desired value of pH by controlling the amount of acid and its salt in case of acidic buffer. What do we mean by an acidic and basic buffer? An acidic buffer solution is simply one which has a pH less than 7. Acidic buffer solutions are commonly made from a weak acid and one of its salts-often a sodium salt. An alkaline buffer solution, on the other hand, has a pH greater than 7. Alkaline buffer solutions are commonly made from a weak base and one of its salts. Frequently used example of acidic and basic buffer include 

-          Acidic buffer: a mixture of CH₃COOH (acetic acid) + CH₃COONa (sodium acetate), citric acid and sodium acetate, boric acid and borax.

-          Basic Buffer:   a mixture of NH₄Cl (ammonium chloride) + NH₄OH (ammonium hydroxide), potassium dihydrogen phosphate (KH₂PO₄), and disodium hydrogen phosphate Na₂HPO₄), sodium carbonate and sodium bicarbonate.                

 3. Methods for determining pH

There are two general methods for determining pH of a solution, one is the colorimetric method and the other most common method is the use of pH meter for determining the pH. In this practical we shall focus only on the principle, method involved in the use of pH meter for determining the pH. So let us get started by first getting to know about the pH meter. 

What is a pH meter?

A pH meter, we have already studied in Practical 1, is a device used for measuring. pH of any unknown solution. It is composed of:

a.       A reference electrode

b.      Glass electrode whose potential depends on the pH of the solution surrounding it

c.       An electrometer, a device capable of measuring very small potential difference in a circuit of extremely high resistance.

Principle

Hydrogen ions in solution, like other ionic species, conduct an electric current. When a glass electrode is dipped in a solution containing hydrogen ions, a potential difference develops across a very thin glass membrane separating two solutions of different hydrogen ion concentration – one within and the other outside the glass electrode. A pH meter is an electronic voltmeter that measures this difference of potential and through its internal calibration, converts it to a pH reading which is displayed on a scale. The scale is normally taken extending from 0 to 14 pH units with a last count of 0.05 pH units or better. A pointing needle moves across the graduated scale and the pH of the solution can be read directly on the scale. These days digital pH meters are becoming more popular as compared to scale – needle instruments. 

With a review of the principle and functions of the pH meter, we are now ready to get started with the experiments related to pH and buffer solutions. There are 3 experiments in this practical. So let us carry out these experiments and learn as we go about conducting the experiments.    

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BLS/CPR and MCQS with answers

 Basic Life Support (BLS) / Cardiopulmonary Resuscitation (CPR) and MCQS

 

 

CPR

cardiopulmonary [kahr″de-o-pul´mo-nar″e]

pertaining to the heart and lungs.

cardiopulmonary resuscitation (CPR) the manual application of chest compressions and ventilations to patients in cardiac arrest, done in an effort to maintain viability until advanced help arrives. This procedure is an essential component of basic life support (BLS), basic cardiac life support (BCLS), and advanced cardiac life support (ACLS). 

The preliminary steps of CPR, as defined by the American Heart Association, are (1) calling for help; (2) establishing unresponsiveness in the victim by tapping or gently shaking and shouting at him or her; (3) positioning the victim in a supine position on a hard surface; (4) giving two breaths; and (5) checking the pulse. These are begun as quickly as possible; prompt action is essential for successful outcome. At the moment breathing and heart action stop, “clinical death” ensues. Within four to six minutes the cells of the brain, which are the most sensitive to lack of oxygen, begin to deteriorate. If breathing and circulation are not restored within this period of time, irreversible brain damage occurs and “biological death” takes place. 

Although CPR is strongly recommended as a life-saving measure, it is not without danger; specific risks include rib fracture, damage to the liver or heart, and puncture of lungs or large blood vessels. All health care providers should receive instruction and practice in CPR under the direction of a qualified instructor. The public in general should also be encouraged to learn CPR for use in emergency situations. 

Once it has been established that a person is in need of CPR, the rescuer immediately begins the “ABC's” of CPR: Airway, Breathing, and Circulation. Opening the airway and determining by look, sound, and feel is the first step for determining whether the person will be able to resume unassisted breathing. This is accomplished by lifting the chin up and back and bringing the mandible forward. If there is no evidence of spontaneous breathing, the rescuer corrects obstruction of the airway by a foreign body, when this is indicated. This is done by one or more of the following methods: back blows, manual chest thrusts, and finger sweeps. Once the airway is open, rescue breathing is started by means of mouth-to-mouth resuscitation (see artificial respiration). 

The third element of CPR is circulation, which begins by establishing the presence or absence of a pulse. If there is no pulse, compression of the chest is begun. This consists of rhythmic applications of pressure on the lower half of the sternum (NOT on the xiphoid process, which may injure the liver). For a normal-sized adult, sufficient force is used to depress the sternum about 4 to 5 cm (1½ to 2 in). This raises intrathoracic pressure and produces the output of blood from the heart. When the pressure is released, blood is allowed to flow into the heart. Compressions should be maintained for one-half second; the same length of time is allowed for the relaxation period. 

Chest compression is always accompanied by rescue breathing. The two must be coordinated so that there is regular and uninterrupted circulation of blood and aeration of the lungs. 

CPR is a psychomotor skill and all health care providers should keep their certification current in order to be proficient in this procedure in case of emergency. The techniques of CPR provide basic life support (BLS) in all cases of respiratory and cardiac arrest. Standards and guidelines for CPR and emergency cardiac care (ECC), including BCLS and ACLS, have been developed cooperatively by the American Heart Association and the National Academy of Sciences–National Research Council. Reprints of these standards can be obtained from local chapters of the Heart Association. 

BLS/CPR_MCQS

Tips When Taking the Practice Exam:

When taking the practice exam, you should answer all the questions. There will be multiple choices, which provide challenging questions and only one is considered as the correct answer.

If you missed or failed to answer a question, you have to take note of it or write it down. Check your notes and textbooks immediately and look for the right answers to the questions and study them again. You can take the practice exam once again and try to answer everything. When you get everything correct on the practice exam, then you will definitely pass and get a good score on the actual Prometric Exam.

1. True or False: The jaw-thrust maneuver should be used to open the airway of an individual with a suspected head or neck injury.

        a. True   - Correct 

        b. False 

2. True or False: It is recommended to minimize interruptions in CPR for pulse checks and shocks. 

        a. True   - Correct 

        b. False 

3. True or False: If you did not witness the arrest of a child or an infant, you should provide two minutes of CPR before leaving them to activate the emergency response system and get the AED. 

        a. True   - Correct 

        b. False 

4. True or False: For infants, an AED is preferred to a manual defibrillator for defibrillation. 

         a. True   

         b. False  - Correct 

5. True or False: If the individual is making high pitched wheezing noises and gasping for air you should encourage them to cough.

          a. True   - Correct     

          b. False   

6. True or False: CPR is performed while a second rescuer gets an AED. 

           a. True   - Correct     

           b. False   

7. True or False: An individual should be "cleared" prior to a shock only when convenient. 

          a. True    

          b. False  - Correct               

8. True or False: If the individual has no pulse and the rhythm is NOT shockable, it is always recommended that you insert advanced airway; then start CPR.

        a. True    

        b. False  - Correct   

9. What are the BLS (Basic Life Support) steps used for adults? 

        a. Assess the individual, active EMS and get AED, check pulse, and start CPR    

        b. Assess the individual, give two rescue breaths, defibrillate, and start CPR  

        c. Check pulse, give rescue breaths, assess the individual defibrillate  - Correct   

         d. None of the above     

10. Which step is Not a part of the six steps in the Adult Chain of survival? 

          a. Advance airway placement  - Correct    

          b. Early CPR   

           c. Integrate post cardiac arrest care 

           d. Rapid defibrillation  

11. What is the compression to ventilation ratio you should use when giving CPR to any adul? 

           a. 15:02     

           b. 15:01     

           c. 30:01

           d. 30:2     - Correct 

 12. When performing two-rescuer CPoles?  

             a. After every cycle of CPR      

             b. After every five cycle of CPR     - Correct  

              c. After 10 cycle of CPR      

              d. After every 15 cycle of CPR       

 12. When performing two-rescuer CPoles?  

                a. After every cycle of CPR      

                b. After every five cycle of CPR     - Correct  

                c. After 10 cycle of CPR      

                d. After every 15 cycle of CPR 

13. When operating an AED, what are the correct steps to follow?  

            a. Power on the AED, attach electrode pads, shock the individual, and analyze rhythm  

            b. Attach electrode pads, check pulse, and analyze rhythm 

            c. None of the above 

            d. Power on the AED, attach electrode pads, lear the individual, analyze the rhythm, and deliver shock   - Correct  

14. When looking for a pulse on a child from one year to puberty, where should you check?  

             a. Brachial artery 

             b. Temporal artery    

             c. Carotid or terminal artery   - Correct  

             d. Popliteal artery  

15. Why are breaths so important for children and infants in cardiac arrest? 

               a. Because they often have respiratory failure that reduces the oxygen content in the blood before the onset of arrest.  - Correct      

               b. Because they have smaller lungs.       

               c. Because breathe help to dislodge foreign bodies  

               d. None of the above  

16. Signs of severe airway obstruction include which of the following?   

                a. Poor air exchange  

                b. High-pitched noise while inhaling     

                c. Inability to speak  

                d. All of the above    - Correct  

17. The rescuers exhaled air contains approximately __________oxygen and _______carbon dioxide.   

                a. 21%, 2%   

                b. 10%, 8%      

                c. 6%, 12%   

                d. 17%, 4%     - Correct  

18. At what age is it necessary to use the child AED pads?     

                a. 10 years of age or younger    

                b. 8 years of age older       

                c. Less than 8 years of age      - Correct 

                d. 13 years of age or younger   

19. How should you attempt to relieve choking in a responsive over the age of one year? 

                a. Back slaps     

                b. Finger sweep        

                c. None of the above   

                d. Abdominal thrusts     - Correct   

20. What is the appropriate way to be clear an objection from an infant's airway?

                a. Back blows and chest thrusts      - Correct    

                b. Abdominal thrusts          

                c. Blind finger sweep    

21. An AED can be used in which of the following special situations? 

                a. Individuals with on implanted pacemaker     

                b. Individual with a transdermal medication patch on           

                c. All of the above      - Correct    

22. What should you do if the individual chest is wet when using an AED? 

                a. Rub isopropyl alcohol on individual skin before proceeding with AED use.      

                b. Do not use an AED device.            

                c. Quickly wipe it dry before proceeding with AED use.     - Correct    

                d. Proceed with AED use as usual.  

23. You are alone when you encounter an individual in what appears to be cardiac or respiratory arrest. What are the first three step should take to stabilize the individual? Check for danger, check for response, and ____________________. 

                a. Administer an initial shock.      

                b. Insert an advanced airways.            

                c. Start CPR     

                d. Activate EMS     - Correct    

24. Which of the following may be essential to maintaining an individual's an airways open?  

                a. O2 administration       

                b. Chest thrusts             

                c. Rescue breaths      

                d. An advanced airways     - Correct    

25. The BLS Survey changed in the 2010 ILCOR update. Which of the following described this change?    

                a. A. Start with chest compressions instead of instead of giving two rescue breaths. 

                b. B. The initial steps are no longer ABC, instead it is CAB: Stat with chest compressions.               

                c. C. Chest compressions should be continued while preparing the AED to minimize  interruptions.     

                d. D. both A and C.   - Correct  

26. Thirty _____________and two _______________equal one cycle of CPR. 

                a. Chest compressions, breaths.        -     Correct  

                b. Breaths, chest compressions              

                c. Chest compressions jaw thrusts       

                d. Chest compressions pulse checks   

27. The initial basic life support (BLS) steps for adults  are: 

                a. Assess the victim, give 2 rescue breaths, defibrillate, stat CPR   

                b. Assess the victim, activate EMS and get AED, check pulse, start CPR  -     Correct  

                c. Check pulse, give rescue breaths, assess the victim, defibrillate        

                d. Assess the victim, start CPR, give 2 rescue breaths, defibrillate

28. The 5 links in the adults chain of survival include all of the following EXCEPT: 

                a. Early CPR    

                b. Rapid defibrillation    

                c. Advanced airway placement        -     Correct      

                d. Integrated post-cardiac arrest care      

29. The critical characteristics of high-quality CPR include which of the following? 

                a. Starting chest compressions within 10 seconds of recognition of cardiac arrest    

                b. Push hard and fast     

                c. Minimize interruptions   

                d. All of the above     -     Correct 

30. In an adults with an advanced airways in place during 2-rescuer CPR,breaths should be administration how often?  

                a. Every 2 to 3 seconds (20 to 30 breaths per minutes)     

                b. Every 4 to 5 seconds (12 to 15 breaths per minutes)     

                c. Every 6 to 8 seconds (8 to 10 breaths per minutes)       -     Correct 

                d. Every 10 to 12 seconds (5 to 6 breaths per minutes)   

31. Where should you attempt to perform a pulse check on a child from 1 year of age to puberty?   

                a. Brachial artery      

                b. Ulnar artery      

                c. Temporal artery    

                d. Carotid or Femoral artery      -     Correct 

32. The guidelines for CPR recommended BLS sequence of steps are:   

                a. Chest compressions, Airway, Breathing     -     Correct

                b. Airway, Breathing, Check pulse          

                c. Airway, Breathing, Chest compressions       

                d. None of the above  

33. Due to the essential nature of washing your The guidelines for CPR recommended BLS sequence of steps are:   

                a. Chest compressions, Airway, Breathing     -     Correct

                b. Airway, Breathing, Check pulse          

                c. Airway, Breathing, Chest compressions       

                d. None of the above   

34. When treating a 3rd-degree burn, you should: 

                a. Before performing CPR   

                b. After performing CPR     -     Correct 

35. An AED (Automated External Defibrillator) should be used:

                a. Cool burn with Ice      

                b. Remove clothing from charred area          

                c. Activate EMS or rush patient to the nearest hospital        -     Correct

                d. None of the above 

36. If patient undergoes a Head Injury it's possible the patient has had a concussion. 

                a. True      -     Correct 

                b. Flse 

37. When performing CPR on an infant (laying face -up), you should use. 

                a. 2 Fingers       -     Correct 

                b. Your Palm  

38. If the patient's chest is not inflating during the breathing task you should check the patient's: 

                a. Airway        -     Correct 

                b. Pulse   

39. A compression rate of 100 - 120 per minute should be performed when providing CPR. 

                a. Ture        -     Correct 

                b. False 

40. When treating Bites & Stings you should use: 

                a. An AED (Automated External Defibrillator)     

                b. An auto-injection      -     Correct 

41. You should ask the patients if He/She is okay before performing CPR. 

                a. True          -     Correct 

                b. False 

42.As a daycare provider that is working alone, one of your three-year-old children isn't feeling well and lays down for a nap. After checking on the child, you notice they are not are not breathing and are blue in color. What would be best step to take?   

                a. Do back blows.    

                b. Do a blind finger sweep       

                c. Deliver two minutes of CPR      -     Correct

                d. None of the above 

43. What do you if an infant is choking and while trying to assist them they become unresponsive?      

                a. Leave the infant to get help 

                b. Do a blind finger sweep       

                c. Begin CPR      -     Correct

                d. Do abdominal thrusts 

44. AED pads can be used for children at what age? 

                a. 17

                b. 16     

                c. 14

                d. Up until puberty           -     Correct

45. An infant become unresponsive and stops breathing. A strong pulse is still present. How many rescue breaths a minute should be given until help arrives or the infant starts breathing on its own? 

                a. 8 - 10 breaths a minute 

                b. 10 - 14 breaths a minute  

                c. 12 - 20 breaths a minute           -     Correct

                d. 15 - 22 breaths a minute   

46. How often should you recheck for a pulse when are performing rescue breaths on an unconscious patient with a pulse?   

                a. Every 45 seconds   

                b. Every 1 seconds  

                c. Every 2 minutes   -     Correct

                d. Every  4 minutes

47. Which of these answers appropriately describes how perform chest compressions on an adults?  

                a. Using one arm, press to 1/3 depth of chest

                b. Palms placed midline on the lower 1/3 of the sternum     -     Correct

                c. Palms placed in center of sternum above the nipples, using both arms  

                d. Compressions should be slow to allow for full recoil 

48. What is the compression to breath ratio when performing CPR on an infant with two providers?

                a. 30:2

                b. 25:2    

                c. 20:2 

                d. 15:2         -     Correct

49. You just performed 5 cycles of CPR on an adult. You reassess for a pulse. No pulse is present. What is your next course of action?  

                a. Search for an AED 

                b. Immediately initiate CPR        -     Correct

                c. All of the above 

                d. None of the above 

50. When should an unconscious patient be placed in the recovery position?  

                a. If the patient has bradycardia and is not breathing 

                b. If the patient has a pulse and is breathing appropriately        -     Correct

                c. If the patient has no pulse and is not breathing 

                d. If the patient has a bounding pulse and is not breathing 

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