The scientist who discovered the blood groups (ABO system) was: MCQ with Answer and Explanation

Explanation:
Lysosomes are single-membrane-bound organelles containing hydrolytic enzymes. Mitochondria, chloroplasts, and the nucleus are double-membrane-bound. Peroxisomes, vacuoles, and the endoplasmic reticulum are also single-membrane structures. The single membrane of lysosomes helps maintain an acidic pH (5.0) for enzyme activity and protects the cell from autolysis.

Explanation:
Mature human RBCs have a lifespan of approximately 120 days, after which they are phagocytosed by macrophages in the spleen and liver. They lack nuclei and organelles, thus cannot repair themselves. New RBCs are produced in the bone marrow at a rate of about 2 million per second. Erythropoietin stimulates RBC production.

Explanation:
Hexokinase phosphorylates glucose to glucose-6-phosphate using ATP, the first step of glycolysis. Phosphofructokinase is the third step, pyruvate kinase the last, glucose-6-phosphatase reverses the reaction in gluconeogenesis.