Tag: science & technology

The human brain consists of several major parts: the cerebrum (largest part, handles higher cognitive functions), the brain stem (connects to spinal cord, controls vital functions), the cerebellum (coordinates movement and balance), and the limbic system (processes emotions and memory). All four options represent valid parts or systems within the brain structure.

Normal human body temperature is approximately 37°C or 98.6°F. 36.9°C falls within the normal range of 36.1-37.2°C. Option A (81.1°C) is impossibly high, while D (21.7°C) is too low for human survival.

Vitamin K is essential for the synthesis of clotting factors in the liver. Without it, blood cannot clot properly, leading to excessive bleeding. Vitamins B1, B2, and D serve different metabolic functions.

An average adult human has approximately 5-6 liters of blood, roughly 7% of body weight. This volume varies with size, gender, and health status. 3-4 liters is too low, while 8-12 liters is impossibly high.

Red blood cells are produced in the bone marrow through erythropoiesis, primarily in flat bones like the sternum, ribs, and pelvis. The liver, kidneys, and heart have other essential functions but do not produce RBCs.

The adult human skeleton has 206 bones. Infants are born with around 270-300 bones, but many fuse together during growth (especially in the skull, spine, and pelvis). The final count of 206 is standard in human anatomy.

The pancreas functions as both an endocrine and exocrine gland. Its endocrine function secretes insulin (which lowers blood sugar) and glucagon (which raises blood sugar). The exocrine function produces digestive enzymes, not bile.

The tibia (shinbone) is the larger of the two bones in the lower leg, connecting the knee to the ankle. It bears most of the body's weight. The fibula is the smaller bone alongside it.

The cerebrum is the largest part of the human brain, making up about 85% of brain weight. It handles thinking, reasoning, memory, language, and voluntary movements. The cerebellum coordinates movement, and the medulla controls vital functions like breathing.

Calcium phosphate (specifically hydroxyapatite, Ca₁₀(PO₄)₆(OH)₂) is the main mineral component of bones and teeth, giving them hardness and strength. It makes up about 65-70% of bone tissue.