Day-424 | Daily MCQs | UPSC Prelims | CURRENT DEVELOPMENTS

Answer: B
Explanation:
Context: Three out of five women, over the age of 40 years, in Mumbai suffer from osteopenia, according to a study conducted by a private city hospital. Doctors attributed age, Vitamin D deficiency, menopause, chronic diabetes or kidney diseases, lack of physical exercise, and sedentary habits as the precipitating factors for their brittle bones. After excluding high-risk groups, the study analysed data from 1921 women, aged between 40-95 years, who underwent Dual-Energy X-ray Absorptiometry (DEXA) scan which measures bone mass density.
● A DEXA scan is an imaging test that measures bone density (strength). DEXA scan results can provide helpful details about your risk for osteoporosis (bone loss) and fractures (bone breaks). This test can also measure your body composition, such as body fat and muscle mass.
● Through Dexa tests, sportsperson and trainers can also measure body fat percentage, lean muscle mass, water content and bone density.

Answer: A
Explanation:
Context: As SpaceX recently abandoned its affordable internet project Starlink in India, Amazon has ramped up its efforts to launch its fast and cheaper internet service called ‘Project Kuiper’ in the country. The Department of Telecommunications (DoT) reprimanded Elon Musk’s Starlink Internet Services for pre-selling and booking the satellite-based internet services without having obtained the necessary licences in the country. It is asked to “refrain from booking/rendering the satellite internet services in India with immediate effect”.
● Starlink is one of a growing number of companies launching small satellites as part of a low-Earth orbiting network to provide low-latency broadband internet services around the world, with a particular focus on remote areas that terrestrial internet infrastructure struggles to reach. Hence option A is the correct answer.
● Starlink plans to carry on the business of telecommunication services’ including satellite broadband internet services, content storage and streaming, multi-media communication, among others.
● It will also deal in devices such as satellite phones, network equipment, wired and wireless communication devices, as well as data transmission and reception equipment

Answer: A
Explanation:
Context: For the first time, farmers in the Philippines have cultivated Golden Rice on a larger scale and harvested almost 70 tonnes of grains recently. Fortified with Vitamin A, the grains will be distributed to households with pregnant women, breastfeeding mothers or preschool children who are at risk of diseases caused by Vitamin A deficiency.
● Statement 1 is correct: Golden rice is a variety of rice (Oryza sativa) produced through genetic engineering to biosynthesize beta-carotene, a precursor of vitamin A, in the edible parts of rice. It is intended to produce a fortified food to be grown and consumed in areas with a shortage of dietary vitamin A.
● Statement 2 is correct: Golden Rice technology is based on the simple principle that rice plants possess the whole machinery to synthesise β-carotene, and while this machinery is fully active in leaves, parts of it are turned off in the grain. By adding only two genes, a plant phytoene synthase (psy) and a soil bacterial phytoene desaturase (crt I), the pathway is turned back on and β-carotene consequently accumulates in the grain.
● Statement 3 is not correct: It wouldn’t suffice to merely introduce one Golden Rice variety onto the market. Vital is that sufficient crop diversity prevails and that varieties are adapted to cultural traditions and are suitable for local cultivation conditions. The Golden Rice trait is therefore crossed in as many varieties as possible. Once on the market conventional breeding work shall continue and new varieties with the trait can be continually added. In several countries, golden rice has been bred with local rice cultivars. Golden rice has not yet been grown commercially, and back crossing is still ongoing in current varieties to reduce yield drag.

Answer: B
Explanation:
Context: One of the four tiger cubs born at Sanjay Gandhi Biological Park (Patna Zoo), has died due to protozoan disease, the zoo authorities informed recently.
● Bacteria like Streptococcus pneumoniae and Haemophilus influenza are responsible for the disease pneumonia in humans which infects the alveoli (air filled sacs) of the lungs. As a result of the infection, the alveoli get filled with fluid leading to severe problems in respiration. The symptoms of pneumonia include fever, chills, cough and headache. Dysentery, plague, diphtheria, etc., are some of the other bacterial diseases in humans.
● Many viruses also cause diseases in human beings. Rhino viruses represent one such group of viruses which cause one of the most infectious human ailments, the common cold. They infect the nose and respiratory passage but not the lungs. Similarly, Measles is a highly contagious infectious disease caused by the measles virus. Symptoms usually develop 10–12 days after exposure to an infected person and last 7–10 days. Initial symptoms typically include fever, often greater than 40 °C (104.0 °F), cough, runny nose, and inflamed eyes.
● Some of the human diseases are caused by protozoans too. For example, malaria, a disease man has been fighting for many years. Plasmodium, a tiny protozoan, is responsible for this disease. Different species of Plasmodium (P. vivax, P. malaria and P. falciparum) are responsible for different types of malaria. Of these, malignant malaria caused by Plasmodium falciparum is the most serious one and can even be fatal. Hence option B is the correct answer.

Answer: B
Explanation:
Context: Scientists have recently identified neurons responsible for regulating the body temperature of mammals, paving the way for technological development which can artificially adjust it to help treat heat stroke, hypothermia, and even obesity, according to a new study. A research group at Nagoya University, Japan, has reported that a group of neurons, called EP3 neurons, in the preoptic area of the brain play a key role in regulating body temperature in mammals. The preoptic area is a part of the hypothalamus that controls the body’s vital functions.
● The Central Nervous System includes the brain and the spinal cord and is the site of information processing and control. The Peripheral Nervous System comprises all the nerves of the body associated with the CNS (brain and spinal cord). The brain is the central information processing organ of our body, and acts as the ‘command and control system’. It controls the voluntary movements, balance of the body, functioning of vital involuntary organs (e.g., lungs, heart, kidneys, etc.), thermoregulation, hunger and thirst, circadian (24-hour) rhythms of our body, activities of several endocrine glands and human behaviour. It is also the site for processing of vision, hearing, speech, memory, intelligence, emotions and thoughts.
● The hypothalamus is a small region of the brain. It’s located at the base of the brain, near the pituitary gland. It synthesizes and secretes neurohormones, often called hypothalamic releasing hormones. These hypothalamic releasing hormones control and regulate the secretion of pituitary hormones.
Functions of the hypothalamus can be listed as:
● controls the release of 8 major hormones by the pituitary gland
● controls body temperature
● control of food and water intake, hunger and thirst
● control of sexual behavior and reproduction
● control of daily cycles in physiological state and behaviour also known as circadian rhythm
● mediation of emotional responses
Hence, option B is correct