CRISPR/Cas9
Why in News: Recently, researchers employed CRISPR/Cas9 to modify photosynthesis for the first time.
About CRISPR/Cas9:
- Definition: CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats, is a gene-editing technology that allows for the modification of specific genes by removing, adding, or altering sections of the DNA sequence.
- Capabilities: This technology enables the correction of genomic errors, and the activation or deactivation of genes in cells and organisms quickly, inexpensively, and with relative ease.
Development:
- Natural Inspiration: Some bacteria possess a gene-editing system similar to CRISPR-Cas9, which they use to combat invading pathogens like viruses, functioning akin to an immune system.
- Mechanism in Bacteria: Bacteria use CRISPR to cut out parts of the viral DNA and retain a segment to help recognize and defend against the virus in future attacks.
- Adaptation: Researchers adapted this bacterial immune defense system to create a method for editing DNA in other organisms.
Components of the CRISPR-Cas9 System:
- Cas9 Enzyme: Acts as ‘molecular scissors’ to cut the two strands of DNA at a specific location in the genome, allowing for the addition or removal of DNA segments.
- Guide RNA (gRNA): Contains a small piece of pre-designed RNA sequence (about 20 bases long) within a longer RNA scaffold.
- The scaffold part binds to the DNA, while the pre-designed sequence guides Cas9 to the correct genome location, ensuring precise cuts by the Cas9 enzyme.
Function:
- Targeting DNA: The guide RNA is designed to locate and bind to a specific DNA sequence.
- Cutting DNA: Cas9 follows the guide RNA to the target location and cuts both DNA strands.
- DNA Repair: Researchers use the cell’s natural DNA repair mechanisms to add, delete, or replace genetic material, facilitating precise genetic modifications.
Potential Applications:
- CRISPR-Cas9 holds significant promise for treating various medical conditions with a genetic component, including cancer, hepatitis B, and high cholesterol.
Sarod
Why in News: Sarod maestro Pandit Rajeev Taranath recently passed away while receiving treatment at a private hospital in Mysuru.
About Sarod:
The sarod is a stringed instrument in the lute family and is one of the most popular instruments in Hindustani classical music.
- It is often accompanied by the tabla (drums) and tambura (drone lute).
- The sarod is an adaptation of the Afghan rabab, introduced to India in the 16th century.
- The modern form of the instrument was developed in the 19th century.
Structure:
- The sarod is 100 cm long with a body made from hollow teak, sagwan, or tun wood.
- High-quality sarods feature a body, neck, and peg box crafted from a single piece of wood.
Resonator:
- It includes a stretched membrane (usually goatskin) and a bridge made from horn for the strings to rest.
- The bridge is thin, similar to that of a violin, supporting melody strings and sympathetic strings that pass through drilled holes.
Strings:
- Traditionally made from gut or silk, modern sarod strings are usually steel or bronze.
Neck:
- Unlike other string instruments, the sarod does not have a fretboard but instead features a polished, steel plate.
Playing:
Terminology: A sarod player is called a sarodiya, and the word “sarod” is Persian for song or melody.
Technique: The seated player holds the sarod across the lap.
- Strings are plucked using a triangle-shaped plectrum called a jawa, typically made from coconut shell, ebony, or horn, while the left hand’s fingernails press the strings.
Schools of Playing:
- Two prominent Indian schools of sarod playing are those of Ghulam Ali Khan and Allauddin Khan.
- Each school has its own playing style, type of sarod (variations in size, shape, and number of strings), and tuning system.
Pradhan Mantri Awas Yojana
Why in News: The Cabinet has resolved to further extend the Pradhan Mantri Awas Yojana by constructing an additional 3 crore houses in rural and urban areas.
About Pradhan Mantri Awas Yojana (PMAY):
Launched by the Government of India in 2015-16, the Pradhan Mantri Awas Yojana aims to assist eligible rural and urban households in constructing houses with basic amenities.
- Houses built under PMAY come with additional amenities like household toilets, LPG connections, electricity, and functional tap connections, achieved through collaboration with other central and state government schemes.
- The scheme has two components: PMAY-U for urban areas and PMAY-G for rural areas.
PMAY-Urban:
Implementation:
- Implemented by the Ministry of Housing and Urban Affairs since June 2015 under the ‘Housing for All’ Mission.
- Provides central assistance to states and Union Territories (UTs) to build all-weather pucca houses with basic civic amenities for eligible urban beneficiaries.
- The scheme is demand-driven, with no fixed target for house construction.
Verticals:
- Beneficiary Led Construction (BLC)
- Affordable Housing in Partnership (AHP)
- In-Situ Slum Redevelopment (ISSR)
- Credit Linked Subsidy Scheme (CLSS)
Central Assistance:
- ₹1.0 lakh under ISSR
- ₹1.5 lakh for AHP and BLC verticals
PMAY-Gramin:
Objective:
- To achieve ‘Housing for All’ in rural areas, the Ministry of Rural Development has been implementing PMAY-G since April 1, 2016.
- Aims to construct 2.95 crore pucca houses with basic amenities by March 2024 for eligible rural households.
Financial Assistance:
- ₹1.20 lakh per house in plain areas
- ₹1.30 lakh per house in hilly states, including North-eastern states, UTs of Jammu & Kashmir and Ladakh, difficult areas, and Integrated Action Plan (IAP) districts
- Additional ₹12,000 for toilet construction
Importance and Progress:
Significance:
- PMAY is a beacon of hope for millions aspiring to own a home, reflecting the government’s commitment to providing affordable housing and enhancing the quality of life.
- It empowers citizens with dignity and security, making it more than just a housing scheme.
Achievements: Under PMAY, a total of 4.21 crore houses have been completed for eligible poor families over the last 10 years.
Crete Island
Why in News: During excavations for an airport on Crete, Greece’s largest island, a large circular monument dating back 4000 years was discovered.
About Microalgae:
- Microalgae are autotrophic microorganisms found in marine, freshwater, and soil ecosystems, producing organic substances through photosynthesis.
- They are a diverse group of microscopic aquatic organisms.
Characteristics:
- Unlike plants, microalgae grow in water instead of on land.
- They absorb nutrients directly rather than through roots.
- While some microalgae can be harmful, others are beneficial and produce useful products.
Outcomes of Recent Study:
- Scientists have identified CGF as a valuable ingredient for various food and feed applications.
- CGF is a promising alternative protein source that can enhance human and animal diets.
- Beyond basic nutrition, CGF promotes overall health, immunity, and well-being.
- Incorporating CGF in poultry diets has been shown to improve egg quality, highlighting its potential as a superior protein supplement in animal nutrition.