Bio Engineering interview questions and answers - part 3

Part 1   Part 2   Part 3   Part 4   Part 5   Part 6 What is blood brain barrier? Blood brain barrier is caused in central nervous system, when blood circulation is separated from the brain extra cellular fluid (BECF). This phenomenon occurs along all capillaries. It consists of tight junctions around the capillaries that do not exist in normal circulation. Cells of the barrier actively transport metabolic products such as glucose across the barrier with specific proteins. This barrier also consists of astrocytic end feet and also includes a thick basement membrane. What is LMO? State some of its importance. LMO stands for living modified organism. LMO are those organisms that have been genetically modified through the application of biotechnology. LMO also includes organisms that have been modified by novel recombinant DNA techniques as well as those that have been modified by mutagenesis or classical breeding and selection techniques. Importance of LMO’s is that they can eat hazardous waste. Explain pathogens. Name some types of pathogens. Pathogens are those organism which feeds on other organism for their food. Pathogens can be transported through many different routes, including airborne, direct or indirect contact, sexual contact, through blood, breast milk, or other body fluids, and through the fecal-oral route. Pathogens can be used to suppress pest population. Different types of pathogens are viral, bacterial, fungal etc. Differentiate 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. 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. Part 1   Part 2   Part 3   Part 4   Part 5   Part 6 Write your comment - Share Knowledge and Experience