Explanation: • The pulmonary artery carries deoxygenated blood from the heart to the lungs, while all other arteries, including the aorta, carry oxygenated blood from the heart to the rest of the body. • Similarly, veins generally carry deoxygenated blood back to the heart, except for the pulmonary vein, which carries oxygenated blood from the lungs to the heart.

Explanation: A surge in luteinizing hormone (LH) triggers ovulation in human females. This hormone is released by the pituitary gland and causes the mature egg to be released from the ovary, marking the process of ovulation.

Explanation: The shape of the chromosome is clearly visible during Metaphase. During metaphase, chromosomes align at the cell's equatorial plate, making them distinct and easy to observe under a microscope.

Explanation: Rafflesia arnoldii, the world's largest flower, is a total root parasite. It grows by taking nutrients and water from the roots of a host plant, instead of producing its own food.

Explanation: Allopatric species are those that are geographically isolated from each other, preventing interbreeding. This isolation typically leads to speciation, where populations evolve into different species over time.

Explanation: Higher plants primarily take up nitrogen in the form of nitrates (NO₃⁻) and ammonia (NH₃). These forms of nitrogen are absorbed from the soil and are then used in various metabolic processes to form amino acids, proteins, and other essential compounds.