Consider statements about the endocrine system: 1. The pituitary gland is called the master gland. 2. The thyroid gland secretes calcitonin. 3. The adrenal medulla secretes cortisol. Which are correct? MCQ with Answer and Explanation

Explanation:
Glycolysis is a cytoplasmic pathway that converts glucose into two pyruvate molecules, producing a net of 2 ATP and 2 NADH. Krebs cycle and ETC are in mitochondria.

Explanation:
Petrified fossils (permineralization) form when dissolved minerals infiltrate the porous tissues of dead organisms and harden, turning the remains into stone while preserving internal structure. Mold and cast fossils are impressions, trace fossils are tracks or burrows. Petrified wood is a common example.

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.