Which of the following statements about meiosis is correct? MCQ with Answer and Explanation

Explanation:
Phosphorus is part of the phosphate backbone of DNA/RNA and the high-energy bonds of ATP. Nitrogen is in bases and amino acids, iron in hemoglobin, sulfur in some amino acids. Phosphorus is essential for energy transfer and genetic material.

Explanation:
The respiratory system, primarily the lungs, facilitates the exchange of gases (oxygen and carbon dioxide) between the blood and the external environment. The circulatory system, centered around the heart and blood vessels, transports blood containing oxygen, nutrients, hormones, and waste products throughout the body. The excretory system, primarily the kidneys, filters blood to remove metabolic waste products and excess water, excreting them as urine. All statements are correct.

Explanation:
Late blight of potato is caused by the oomycete Phytophthora infestans (historically considered a fungus). It caused the Irish Potato Famine. Tobacco mosaic is viral, citrus canker is bacterial (Xanthomonas), crown gall is bacterial (Agrobacterium tumefaciens). Fungal plant diseases also include rust, smut, and powdery mildew. Oomycetes are now classified under Chromista but traditionally studied in mycology.