Structural Organisation in Animals MCQs

Consider the following statements regarding the anatomy of the frog's kidney:

I. The excretory system consists of a pair of kidneys, ureters, cloaca, and urinary bladder.
II. Kidneys are compact, dark red, and bean-like structures.
III. Kidneys are situated anteriorly in the body cavity on both sides of the vertebral column.
IV. Each kidney is composed of several structural and functional units called uriniferous tubules or nephrons.

Consider the following statements regarding sex-specific excretory pathways and nitrogenous waste:

I. In male frogs, two ureters emerge from kidneys and act as urinogenital ducts opening into the cloaca.
II. In female frogs, ureters and oviducts join together to form a common duct before opening into the cloaca.
III. The thin-walled urinary bladder is present ventral to the rectum and opens into the cloaca.
IV. The frog is an ammonotelic animal as it excretes ammonia to conserve water.

Consider the following statements about chemical coordination and endocrine glands in frogs:

I. Chemical coordination of various organs of the body is achieved by hormones secreted by endocrine glands.
II. Pituitary, thyroid, parathyroid, and thymus are prominent endocrine glands found in frogs.
III. Pineal body, pancreatic islets, adrenals, and gonads are endocrine glands present in frogs.
IV. Hormones are carried to target sites by specialized endocrine ducts.

Consider the following statements regarding the nervous system organization of the frog:

I. The nervous system is organised into a central nervous system, a peripheral nervous system, and an autonomic nervous system.
II. The peripheral nervous system consists of the brain and spinal cord.
III. The autonomic nervous system consists of sympathetic and parasympathetic divisions.
IV. There are ten pairs of cranial nerves arising from the brain.

Consider the following statements regarding the structural parts of the frog's brain:

I. The brain is enclosed in a bony structure called the brain box or cranium.
II. The fore-brain includes olfactory lobes, paired cerebral hemispheres, and an unpaired diencephalon.
III. The mid-brain is characterised by a pair of optic lobes.
IV. The hind-brain consists of the cerebellum and medulla oblongata.

Analyze the following statements regarding the connection between the brain and the spinal cord:

I. The medulla oblongata passes out through the foramen magnum and continues into the spinal cord.
II. The spinal cord is enclosed in the vertebral column.
III. The brain is divided into fore-brain, mid-brain, and hind-brain.
IV. There are twelve pairs of cranial nerves arising from the brain.

Consider the following statements regarding the sensory organs of the frog:

I. Organs of touch (sensory papillae), taste (taste buds), and smell (nasal epithelium) are highly complex, well-organized structures.
II. Eyes and internal ears are well-organized, distinct structures in the frog.
III. Cellular aggregations around nerve endings form the simpler sensory structures.
IV. External ears are well-developed and visible as large structures on the lateral side of the head.

Analyze the following statements regarding the structural features of the frog's eye:

I. Eyes in a frog are a pair of spherical structures situated in the orbits of the skull.
II. The eyes of a frog are simple eyes, possessing only a single unit.
III. While in water, a protective nictitating membrane covers the eyes.
IV. Frogs possess compound eyes similar to insects, allowing them to detect moving prey easily.

Consider the following statements regarding the anatomy and functions of the frog's ear:

I. Only the tympanum can be seen externally on the head of the frog.
II. The ear in frogs functions purely as an organ of hearing.
III. The ear acts as an organ of hearing as well as balancing (equilibrium).
IV. Internal ears are absent, and hearing is achieved entirely by the external tympanic membrane.

Consider the following statements regarding the male reproductive organs of the frog:

I. The male reproductive organs consist of a pair of yellowish, ovoid testes.
II. Testes are found adhered to the upper part of the kidneys.
III. The testes are attached to the kidneys by a single fold of peritoneum called mesorchium.
IV. The attachment membrane is a double fold of peritoneum called the mesorchium.