The term for the death of brain tissue due to lack of blood flow is: MCQ with Answer and Explanation

Explanation:
Carbohydrates are the body's primary and most efficient source of energy, broken down into glucose to fuel cellular activities and physical exertion. Proteins are essential macronutrients composed of amino acids, crucial for the growth, maintenance, and repair of body tissues, as well as forming enzymes, hormones, and antibodies. Fats are essential macronutrients; they provide concentrated energy, are vital for cell membrane structure, aid in the absorption of fat-soluble vitamins, and provide essential fatty acids. They should not be entirely avoided. Thus, statements 1 and 2 are correct.

Explanation:
Emil Fischer proposed the lock-and-key model in 1894 to explain enzyme specificity. Koshland modified it to induced fit. Krebs discovered the citric acid cycle, Mitchell chemiosmosis.

Explanation:
Phycoerythrin is a red phycobiliprotein that masks chlorophyll in red algae (Rhodophyta). Phycocyanin is blue in cyanobacteria, fucoxanthin brown in brown algae. These accessory pigments allow light absorption at depths.