Tips to prepare for Biomedical Interview by Pritish Kumar Halder

1) What do you know about DNA fingerprinting?

DNA fingerprinting or genetic fingerprinting is a technique wherein a DNA sequence is used for identification of an individual. It is mostly used in forensics. Polymerase Chain Reaction and Short Tandem Repeats techniques are commonly used for DNA fingerprinting.

2) What is therapeutic cloning?

Cloning is a method of duplicating a DNA or a part of the DNA. Therapeutic cloning otherwise called somatic cell nuclear transfer is a process where an embryo is utilized. The embryo contains stem cells, which can be used in regeneration applications. Embryonic stem cells have the capability of renewing and are pluripotent that is it can transform or grow into more than 220 types of cells of the human body.

3) What do you know about microarray?

Microarrays are arrays where DNA oligonucleotides of DNA sequences are spotted as a matrix. Microarrays are used in gene expression profiling, single nucleotide polymorphism detection, detection of alternative splicing etc. Microarrays perform hybridization of cDNA using probes. A microarray chip has the capability to perform a large set of genetic related experiments simultaneously.

4) What are the most commonly used technologies in medical imaging?

Electron microscopy, Computer Tomography, radiography, thermography, nuclear medicine, fluoroscopy, ultrasound, Positron Emission Tomography and Magnetic Resonance Imaging.

5) Define epilepsy?

Epilepsy is a neurological disorder. It occurs due to abnormal signals in the human brain. These abnormal signals cause seizures and unconsciousness.

6) Explain Alzheimer’s disease?

Alzheimer’s is a brain disease caused due to tau protein misfolding. It is an incurable disease and can be diagnosed in a PET or MRI scan. Alzheimer’s is related more to ageing, where the disease is detected in humans more than 65 years of age. The symptoms are memory loss, stress, confusion and also aggression. Diagnosis is mostly done by behaviour related tests.

7) What are the wave patterns seen in an EEG scan?

Wave patterns seen in an EEG scan are delta – state of sleep, theta drowsiness, alpha – relaxation, beta – active thinking and gamma. Alpha also contains a mu-rhythm

8) What is MRI?

MRI is Magnetic Resonance Imaging. It is a medical imaging technique that gives a detailed structure of internal organs, especially soft tissues. MRI uses a strong magnetic field and generates images and models of the specified organ.

9) What is BMI?

BMI is Body Mass Index. It is a comparison of a person’s height and weight. It is a person’s weight divided by the square of the height. Its SI unit is kg/sq.m.

10) what is myoelectric control?

Myoelectric control uses the signals from a residual limb for the movement of the prosthetics. Myoelectric control technologies obtain signals from the skin on the limbs.

11) Define Biomedical Engineering?

Biomedical engineering is an application of engineering in medicine. It combines the expertise of life sciences, engineering and medicine. Biomedical engineering deals with design and development of advanced medical devices, artificial replacement of organs, devices and methods for disease diagnosis and DNA chips. Biomedical engineering is one of the upcoming fields with its reach expanding exponentially every day.

12) What Are Immunoglobulins? Explain Its Structure?

Immunoglobulins are popularly known as antibody. These are large Y-shaped protein produced by B-cells that is used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. Immunoglobulins are “Y” shaped structure which is having two tips and each tip of immunoglobulins contains a paratope. Immunoglobulins are typically made of basic structural units-each with two large heavy chains and two small light chains. The general structure of all antibodies is very similar; a small region at the tip of the protein is extremely variable.

13) What Is Frame Shift Mutation? Is This Mutation Similar To Single-nucleotide Polymorphism?

This is the type of mutation in which DNA sequence is changed due to addition and deletion of nucleotides. This mutation changes the code for amino acids. This is also called framing error or reading frame shift. This mutation will cause the reading of the codons after the mutation to code for different amino acids. No, this mutation is not similar to single-nucleotide polymorphism. In single-nucleotide polymorphism nucleotide is replaced, rather than inserted or deleted.

14) Difference Between Retrovirus And Provirus?

A retrovirus is a RNA virus which can be duplicated in a host cell using the reverse transcriptase enzyme. It can produce DNA from its RNA genome. The produced DNA is then incorporated into the host’s genome by anintegrase enzyme. The RNA virus thereafter replicates as part of the host cell’s DNA. Retroviruses are enveloped viruses that belong to the viral family Retroviridae.
Provirus is a virus genome which can integrate into DNA of host cell. In inactive viral infections the virus will not replicate itself but through replication of its host cell. This state can last over many host cell generations.

15) What Is Prosthetic Limb? What Are Its Drawbacks?

It is an artificial device which can be used to replace a missing body part. It is based on the principle of biomechatronics. It can be used to replace body part missing from birth, due to injury or due to defect. The main drawback of prosthetic limb is its cost. Moreover, prosthetic limbs have to be replaced every 3-4 year due to the wear and tear. If the limb has fit tissues then the sockets in the limb have to be replaced every month.

16) What is the Mechanism Of Elisa. What Are Its Uses?

ELISA stands for enzyme linked immunosorbent assay. It is a wet lab type analytical biochemistry assay. It can detect presence of a substance in a liquid or wet sample by using one subtype of heterogeneous, solid-phase enzyme immunoassay. ELISA can be used as ligand binding assays. It is also used as a diagnostic tool in medicine and plant pathology. Quality check operations can also be performed in various industries with the help of ELISA.

17) What Is Isotopic Tracer Technique?

This technique is used to understand chemical reaction and interactions in bio-chemistry and chemistry. In this technique, one or more of the atoms of the molecule of interest is substituted for an atom of the same chemical element, but that element belongs to different isotope. It can be used to detect the difference in number of neutrons separately from the other atoms of the same element. The atom has the same number of protons; it will behave in almost exactly the same way chemically as other atoms in the compound, and with few exceptions will not interfere with the reaction under investigation.

18) Difference Between Gram Positive And Gram Negative Bacteria?

In gram staining protocol, gram positive bacteria are stained dark blue or violet. Crystal violet stain can be retained by the gram positive bacteria because of the high amount of the peptidoglycan in the cell wall. Gram-positive cell walls typically lack the outer membrane found in Gram-negative bacteria.
In gram staining protocol, gram negative bacteria do not retain crystal violet dye. Gram negative bacteria have pathogenic capability. Gram negative bacteria have cytoplasmic membrane which is not present in gram positive bacteria.

19) Sometimes staff members benefit from learning about the makeup of a piece of medical equipment. Are you comfortable explaining how a machine works to other employees?

I can help doctors, nurses and other coworkers familiarize themselves with the equipment that they’ll be using every day so that they can better assist their patients. By telling them what they need to know, they can better understand what can go wrong. I’m generally friendly and collaborate easily with others.

20) What Is Superiority Of Tlc Over Paper Chromatography?

TLC is superior over paper chromatography because of inorganic nature of adsorbent concentrated sulfuric acid spray. The spray is then followed by heating. It may be used to develop on the chromatogram by charring. Also, amino acid mixtures require 18 hours for separation on paper. It requires 3 hrs using cellulose TLC. The advantages of TLC lie in adsorbents which don’t allow separation on paper. In TLC we have much wider choice of adsorbents depending upon needs and sample.