Consider the following statements about the nervous system: 1. Motor neurons carry impulses from the CNS to effectors. 2. Sensory neurons carry impulses from receptors to the CNS. 3. Interneurons are found only in the peripheral nervous system. Which of the above is/are correct? MCQ with Answer and Explanation

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:
Restriction enzymes cut DNA at recognition sites, DNA ligase seals fragments, and PCR amplifies specific DNA sequences. All three are fundamental tools in biotechnology.

Explanation:
Phosphorus is a primary macronutrient (along with nitrogen and potassium) required in relatively large amounts for nucleic acids, ATP, and phospholipids. Iron, zinc, and copper are micronutrients needed in trace amounts. Macronutrients include C, H, O, N, P, K, Ca, Mg, S. Micronutrients function as enzyme cofactors.