All Free Biology MCQs with Answers

• A. Malaria
• B. Dengue
• C. Thypoid
• D. Tetanus

Explanation: Tetanus is a bactenal infection which can be treated by anti-tetanus serum. Passive immunity can occur naturally, such as when an infant receives a mother's antibodies through the placenta or breast milk, or artificially, such as when a person receives antibodies in the form of an injection (gamma globulin injection).

• A. Healthy Gene
• B. Chromosome
• C. Protein
• D. Carbohydrate

Explanation: This option is the correct answer. In cystic fibrosis, liposomes (microscopic vesicles) can be used as a delivery system for introducing a healthy gene into cells affected by the disease. This technique, known as gene therapy, aims to replace or supplement the faulty CFTR gene responsible for cystic fibrosis with a functional one.

• A. CaCl2
• B. NaCl
• C. KCl
• D. NaOH

Explanation: CaCl2: This option is the correct answer. Bacterial cells are often treated with a solution of calcium chloride (CaCl2) during a process called "calcium chloride transformation" to increase their ability to take up recombinant plasmids. The treatment with CaCl2 helps to create temporary pores in the bacterial cell membrane, allowing the plasmids to enter the cells.

• A. Phage DNA
• B. Genomic Library
• C. Recombinant DNA
• D. Gene Probe

Explanation: A gene probe is a short DNA or RNA sequence that is complementary to a specific target sequence of DNA or RNA. Gene probes can be labeled with various markers, including radioactive nucleotides. The radioactively labeled nucleotides allow for the detection and visualization of the gene probe when it binds to its complementary target sequence.A gene probe is a short DNA or RNA sequence that is complementary to a specific target sequence of DNA or RNA. It is used to detect and identify the presence or absence of the target sequence in a sample.

• A. Embryonic Stem Cell mediated Transfer
• B. Microinjection
• C. Retro-virus mediated gene Transfer
• D. Virus vectors

Explanation: Microinjection: This option is the correct answer. Microinjection is a technique commonly used in transgenic animal research. In this technique, a desired gene is directly injected into the pronucleus of a fertilized egg or the nucleus of a developing embryo. The injected gene becomes incorporated into the genome of the animal, leading to the expression of the desired gene in its offspring.

• A. Viruses
• B. Chromosomes
• C. Enzymes
• D. Genes

Explanation: Enzymes are essential to DNA recombinant technology, and help modify and change DNA molecules as per need.

• A. Restriction enzyme
• B. Microsatellites
• C. Macrosatellites
• D. Probes for genetic markers

Explanation: In DNA fingerprinting, probes for genetic markers are used to identify markers such as microsatellites and thus produce distinctive patterns on autoradiography and X-ray films.

• A. Genetic material
• B. Enzymes
• C. Vectors
• D. Probes

Explanation: Plasmids are small, circular, double-stranded DNA molecules, which are used in DNA recombinant technology by modifying the plasmid and then introducing them into cells

• A. Polymerase chain reaction
• B. Gene sequencing
• C. Analyzing DNA
• D. DNA finger printing

Explanation: It is used to replicate a few or even a singular DNA molecule into millions of copies. It is very specific the target DNA sequence can be less than one part in a million of the total DNA sample

• A. Cystic fibrosis
• B. Hypercholesterolemia
• C. Severe combined immunodeficiency syndrome
• D. Parkinson's disease

Explanation: Adenosine deaminase deficiency is an inherited disorder, which causes severe combined immunodeficiency syndrome, and it causes the afflicted person to have virtually no immunity to bacteria, viruses or fungi.