Question

The organ of the kidney and ureter in Rana tigrina is
A) All mesodermal
B) All endodermal
C) Mesodermal and ectodermal
D) Endodermal and Mesodermal

Answer 1

Rana is a frog family that includes the Holarctic true frogs, pond frogs, and brown frogs. This genus is distributed in most of Eurasia and western North America. Previously, many other genera were included here. These true frogs are typically large species with slender waists and wrinkled skin.

Complete answer:
The three germ layers (ectoderm, mesoderm, and endoderm) are present at the end of gastrulation and give birth to various parts. The ectoderm is responsible for the formation of the central nervous system (brain and spinal cord), the peripheral nervous system, the sensory epithelia of the eye, ear, and nose, the epidermis, mammary gland, and pituitary gland.

The mesoderm is responsible for the formation of connective tissue (cartilage and bone), striated and smooth muscles, heart walls, blood and lymph vessels and cells, kidneys, gonads, and genital ducts, and the spleen. Internal organs are mainly made by mesoderm. Rana tigrina's kidney and ureter emerge from the mesodermal layer.

The endoderm is responsible for the epithelial lining of the gastrointestinal and respiratory tracts, as well as the parenchyma of the tonsils, kidneys, thymus, thyroid, parathyroids, and pancreas, as well as the epithelial lining of the urinary bladder and urethra.

Thus the correct answer is option ‘A’ .

Note: Embryonic cells divide early and develop an outer layer of cells called the ectoderm and an inner layer called the endoderm. The mesoderm forms later, and these three germ layers give birth to all of the tissues of the developing embryo. Rana tigrina's kidney and ureter emerge from the mesodermal layer.