Control, Coordination, Sense Organs and Reproduction in the Frog
This quiz closes the course Structural Organisation in Animals by examining how Rana tigrina governs itself through two interlocking systems: the fast nervous system and the slower, chemically broadcast endocrine glands.
You will be tested on:
- The eight prominent endocrine glands and the hormones that coordinate distant organs
- The central, peripheral and autonomic divisions of the nervous system
- Brain divisions and the ten pairs of cranial nerves
- The five categories of sense organs, including the eyes and the tympanum
- Male reproductive organs: testes, mesorchium, vasa efferentia, Bidder’s canal and the urinogenital duct
- Female reproductive organs: ovaries and oviducts, and the 2500 to 3000 ova laid at a time
- External fertilisation, the tadpole larva and metamorphosis
- The frog’s benefits to mankind and its place in food chains and food webs
Every count and anatomical relationship tested here is preserved exactly as given in the lesson. Read each question carefully and choose the single best answer.
Q1. Which of the following is NOT listed among the prominent endocrine glands of the frog?
The lesson lists the prominent endocrine glands as pituitary, thyroid, parathyroid, thymus, pineal body, pancreatic islets, adrenals and gonads. The spleen is not among them.
Q2. Chemical coordination of the various organs of the frog's body is achieved by hormones that are secreted by endocrine glands and then:
Hormones are secreted by endocrine glands and carried through the bloodstream to their targets, which is why the circulatory system acts as the delivery network for chemical messengers.
Q3. The nervous system of the frog is organised into which three divisions?
The lesson states that the nervous system is organised into a central nervous system (brain and spinal cord), a peripheral nervous system (cranial and spinal nerves) and an autonomic nervous system (sympathetic and parasympathetic).
Q4. How many pairs of cranial nerves arise from the brain of the frog?
There are ten pairs of cranial nerves arising from the brain of the frog.
Q5. Which part of the frog's brain is characterised by a pair of optic lobes?
The midbrain is characterised by a pair of optic lobes. The fore-brain includes olfactory lobes, cerebral hemispheres and diencephalon, while the hind-brain consists of the cerebellum and medulla oblongata.
Q6. The medulla oblongata passes out through the foramen magnum and continues into which structure?
The medulla oblongata passes out through the foramen magnum and continues into the spinal cord, which is enclosed in the vertebral column.
Q7. In the frog, the organs of touch are the:
The organs of touch in the frog are the sensory papillae. Taste buds are organs of taste, nasal epithelium of smell, and the tympanum with internal ears of hearing.
Q8. Which statement about the frog's eyes is correct?
The eyes of the frog are a pair of spherical structures situated in the orbit in the skull, and they are simple eyes possessing only one unit.
Q9. Which sense organs of the frog are described as well-organised structures, while the rest are cellular aggregations around nerve endings?
Out of the frog's sense organs, the eyes and internal ears are well-organised structures, and the rest are cellular aggregations around nerve endings.
Q10. The testes of the frog are adhered to the upper part of the kidneys by a double fold of peritoneum called the:
The pair of yellowish ovoid testes is found adhered to the upper part of the kidneys by a double fold of peritoneum called the mesorchium.
Q11. The vasa efferentia of the frog are 10 to 12 in number, arise from the testes, enter the kidneys on their side and open into the:
The vasa efferentia enter the kidneys on their side and open into Bidder's canal, which finally communicates with the urinogenital duct that opens into the cloaca.
Q12. Which statement about the female reproductive organs of the frog is correct?
The ovaries are situated near the kidneys with no functional connection with them, and a pair of oviducts arising from the ovaries opens into the cloaca separately.
Q13. A mature female frog can lay how many ova at a time?
A mature female can lay 2500 to 3000 ova at a time.
Q14. In the frog, fertilisation is external and takes place in water. Development involves which larval stage?
Development involves a larval stage called the tadpole, which undergoes metamorphosis to form the adult.
Q15. Why are frogs considered beneficial to mankind and important to the ecosystem?
Frogs are beneficial because they eat insects and protect the crop, and they maintain ecological balance by serving as an important link of food chain and food web in the ecosystem.