The structure that prevents the backflow of urine from the bladder to the ureters is the: MCQ with Answer and Explanation

Explanation:
Viruses are non-living outside a host; they cannot carry out metabolic processes or reproduce independently. They hijack the host cell's machinery to replicate. Thus, they are obligate intracellular parasites. The reason correctly explains the assertion.

Explanation:
Ginger is a rhizome, an underground modified stem growing horizontally, bearing nodes, internodes, scale leaves, and buds. Potato is a tuber, gladiolus a corm, onion a bulb (modified stem with fleshy leaf bases). Rhizomes store food and aid vegetative propagation.

Explanation:
Carbohydrates are the body's primary and most readily available source of energy, broken down into glucose for immediate cellular use. Proteins are essential 'body-building' foods, providing amino acids necessary for the growth, repair, and maintenance of tissues, muscles, and enzymes. Fats are essential macronutrients; they provide concentrated energy, are crucial for cell membrane structure, aid in the absorption of fat-soluble vitamins, and provide essential fatty acids. Thus, statements 1 and 2 are correct.