Amniocentesis is a pre-natal diagnostic test based on the chromosomal pattern of the cells in the amniotic fluid that surrounds the developing foetus in the womb. It   is misused to detect the *** of pre-bom child that leads to female foeticide in the case of girl-child.

• PCR stands for Polymerase Chain Reaction.
• Multiple copies of the gene of interest is synthesized in vitro using two sets of primers and the enzyme DNA polymerase.
• Primers are small chemically synthesized oligonucleotides that are complementary to the regions of DNA.
• PCR includes three major steps-

1. Denaturation

2. Annealing

3. Extension

In snapdragon (Antirrhinum ****) the cross between a red-flowered plant (RR) and a white-flowered plant (rr) results in all pink flowered (Rr) plants in the F1 generation. A self-cross between two F1 plants results in red, pink and white flowers in the ratio of 1:2:1.  The genotype of the resulting plants is also in the ratio of 1:2:1 for RR (red), Rr (pink) and rr (white) flowered plants. The cross can be shown as in the image. This is called incomplete dominance. Due to this reason, the F2​ phenotypic ratio and genotypic ratios are same in a cross between red-flowered and white flowered snapdragon plants.

Microbes play an important role in organic farming, which is done without the use of chemical fertilizers and pesticides. Bio-fertilizers are living organisms which help increase the fertility of soil. It involves the selection of beneficial micro-organisms that help in improving plant growth through the supply of plant nutrients. Bio-fertilizers are introduced in seeds, roots, or soil to mobilize the availability of nutrients. Thus, they are extremely beneficial in enriching the soil with organic nutrients. Many species of bacteria and cyanobacteria have the ability to fix free atmospheric nitrogen. Rhizobium is a symbiotic bacteria found in the root nodules of leguminous plants. Azospirillium and Azotobocter are free living nitrogen-fixing bacteria, whereas Anabena, Nostoc andOscillitoria are examples of nitrogen-fixing cyanobacteria. Bio-fertilizers are cost effective and eco-friendly.

Suspend activities for a brief period till the stressful conditions go (Hibernate or aestivate), migrate – move away to afar off place and return when stressful period is over. Example: Bears hibernate and birds migrate. If an organism cannot survive in a particularly stressful external environmental condition then it will undergo hibernation and aestivation which are the periods of dormancy. In the dormant condition, the organism will lower its needs.
And when the conditions are really sustainable and favourable for the organism, the dormant condition will have an end. In case of animals hibernation is the winter sleep and aestivation is the summer sleep by which they escape the external conditions.

Maintenance of personal and public hygiene is very important as safeguard against infectious diseases.

Measures for personal hygiene include:

• Keeping the body clean
• Consumption of clean drinking water, food, vegetables, fruits, etc.
  
  Measures for public hygiene includes:
• Proper disposal of waste and excreta
• Periodic cleaning and disinfection of water reservoirs pools, cesspools and tanks
• Observing standard practices of hygiene in public catering 
• In cases of air-borne diseases such as pneumonia and common cold, close contact with the infected persons or their belongings should be avoided.
• For diseases transmitted through insect vectors, the most important measure is to control or eliminate the vectors and their breeding places.

A locus is the specific physical location of a gene or other DNA sequence on a chromosome, like a genetic street address. The plural of locus is "loci". Alleles are variants of the same gene that occur on the same place on a chromosome. (Through a mutation, they are different.) A locus refers to the location on the chromosome where the gene is found. Loci is the plural form of locus.

Given: GG and Gg are both green pods. This means that G is dominant and g is the recessive allele.

The given Punnet square-

Gg ----> G      g

GG

G         GG     Gg

G         GG    Gg

The given progeny are GG, GG, Gg, Gg.

Since G is the dominant allele, so all the progenies will have green pod. Hence, 100% of the progenies have green pods.

Antibiotics always sold in combination with lactobacillus

• Antibiotics may kill even the useful bacteria present in the digestive tract LAB will protect some microbes in the digestive tract and enhance the production of vitamin B12.

• Lactobacillus acidophilus is a type of bacteria found in your intestines. It's a member of the Lactobacillus genus of bacteria, and it plays an important role in human health. Its name gives an indication of what it produces — lactic acid. It does this by producing an enzyme called lactase.

• Lactobacillus being the most commonly used probiotic agent improves growth performance, feed conversion efficiency, nutrient utilization, intestinal microbiota, gut health and regulates immune system.

The primary lymphoid organs are bone narrow and thymus where immature lymphocytes differentiate into antigen sensitive lymphocytes. The secondary lymphoid organs are spleen, lymph nodes, tonsils. Payer's patches of small instestine and appendix.

Gene silencing, often used in context of RNA interference (RNAi), is a regulatory pathway by which the expression of a gene is suppressed.  Although a gene may be silenced at the transcriptional or post-transcriptional stages, RNAi is specifically a post-transcriptional gene silencing (PTGS) mechanism achieved by cellular introduction of a double stranded RNA (dsRNA) termed siRNA or microRNA.

Gene silencing occurs naturally in cells, and is thought to play a large part in the overall regulation of gene expression in many organisms, giving them protection from viral infections and other undesirable elements.  Recent advances in gene silencing for basic research have lead to the concept of RNAi therapeutics against incurable diseases including hepatitis, cancer, viral infections and HIV by suppressing the expression of genes responsible for promoting these particular diseases.  Gene silencing takes place by degrading the mRNA required for protein synthesis.  In the absence of template mRNA, the cell is rendered incapable of producing proteins, thus suppressing expression and availability of the target protein.

While studying Biology, students would have encountered a topic named asexual reproduction. One of the known asexual reproduction types is known by the name ‘fragmentation’.  As the name is quite self-explanatory, it is a type of cloning where one organism is divided into minor fragments. Once divided, these fragments develop into individual ones which are fully grown. 

A biome can be defined as a large biological community or an ecosystem where different types of living organisms including plants, animals, birds, insects, and humans are used to living in a certain type of climate. The world comprises a huge diversity of the types of environments which are divided and grouped into different types of biomes and are mainly based on the adaptations, range of temperature, weather, and climatic conditions.

Reproduction is a biological process wherein younger ones produced are identical to their parents. This phenomenon is significant in the continuity of the species, generation after generations. Typically, reproduction is observed in all living organisms from single-celled entities such as amoeba to multicellular entities of the most advanced forms such as human beings. Reproduction is carried out in two modes depending upon the participation of one or both parents.