Which digestive enzyme breaks down lactose into glucose and galactose? MCQ with Answer and Explanation

Explanation:
Vaccines induce active immunity (antibodies + memory). Active takes time, passive is immediate but no memory. Innate is nonspecific.

Explanation:
Meristem culture, a type of tissue culture, involves excising the virus-free apical meristem (shoot tip) and growing it on a nutrient medium to produce a whole plant free of viruses. This is because meristematic cells lack vascular connections through which viruses spread. Cloning produces identical copies, hybridization crosses varieties, mutagenesis uses mutagens.

Explanation:
Diabetes insipidus results from ADH deficiency (or resistance), causing polyuria, polydipsia, and dilute urine. Diabetes mellitus is insulin-related, Addison's is adrenal insufficiency, Cushing's is excess cortisol.