Consider statements about plant biology: 1. The stigma is the receptive part of the carpel. 2. The anther is the pollen-producing part of the stamen. 3. The ovary develops into the seed after fertilization. Which are correct? MCQ with Answer and Explanation

Explanation:
Root pressure is a positive hydrostatic pressure generated in the xylem of roots due to the active secretion of ions into the xylem, which lowers the water potential and causes water to enter osmotically from the soil. This pressure can push water up the stem. Root pressure is most evident and measurable during the early morning or at night, when the rate of transpiration from the leaves is very low (or zero) and the soil moisture is high, allowing for maximum water absorption. It is responsible for phenomena like guttation and the exudation of sap from cut stems.

Explanation:
Sponges are the simplest multicellular animals with a cellular level of organization (no true tissues or organs). They are mostly marine, sessile, filter feeders. Water enters through numerous pores (ostia) into a spongocoel and exits through the osculum. They lack a nervous system. They possess specialized cells like choanocytes and amoebocytes but no coordination.

Explanation:
Plasma cells, differentiated from B lymphocytes, are the factories that produce and secrete large amounts of antibodies (immunoglobulins) specific to an antigen. Macrophages phagocytose, T cells regulate or directly kill, neutrophils phagocytose bacteria.