Consider the following statements regarding food ingestion and digestion in the stomach of a frog:
I. Food is captured by the single-lobed, pointed tongue of the frog. II. Digestion of food takes place by the action of HCl and gastric juices secreted from the walls of the stomach. III. Partially digested food, called chyme, is passed from the stomach into the duodenum. IV. The duodenum receives bile and pancreatic juice through a common bile duct.
Explanation: Statement I is incorrect because frogs capture food with a bilobed tongue. Statements II, III and IV are correct because gastric juice and HCl act in the stomach, chyme enters the duodenum, and bile and pancreatic juice reach the duodenum through a common bile duct.
Question 12 of 101
📘 CLASS XI
Consider the following statements regarding the roles of digestive fluids and absorption in the frog's intestine:
I. Bile is secreted by the gall bladder where it is also synthesized. II. Bile emulsifies fat, and pancreatic juice contains digestive enzymes to digest carbohydrates and proteins. III. Final digestion of food takes place in the stomach of the frog. IV. Digested food is absorbed by numerous finger-like folds in the inner wall of the intestine called villi and microvilli.
Explanation: Statement I is incorrect because bile is synthesized by the liver and stored in the gall bladder. Statement II is correct because bile emulsifies fats and pancreatic enzymes digest carbohydrates and proteins. Statement III is incorrect because final digestion occurs in the intestine. Statement IV is correct because villi and microvilli absorb digested nutrients.
Question 13 of 101
📘 CLASS XI
Consider the following statements regarding excretory waste passage and cloacal anatomy:
I. The undigested solid waste moves into the rectum and passes out through the cloacal aperture. II. The cloaca is a small, median chamber used strictly to pass faecal matter to the exterior. III. In male frogs, ureters act as a urinogenital duct that opens into the cloaca. IV. A thin-walled urinary bladder is situated dorsal to the rectum and opens into the cloaca.
Explanation: Statement I is correct because undigested solid waste passes from the rectum through the cloacal aperture. Statement II is incorrect because the cloaca is a common chamber for faecal matter, urine and sperms. Statement III is correct because in male frogs the ureters function as urinogenital ducts opening into the cloaca. Statement IV is incorrect because the urinary bladder is situated ventral to the rectum.
Question 14 of 101
📘 CLASS XI
Analyze the following statements regarding respiration in frogs:
I. In water, the skin acts as an aquatic respiratory organ (cutaneous respiration). II. Dissolved oxygen in water is exchanged through the skin by diffusion. III. On land, the buccal cavity, skin, and lungs act as respiratory organs. IV. Pulmonary respiration refers to respiration by lungs, which are a pair of pink-coloured, elongated, sac-like structures.
Explanation: All four statements are correct. Frogs perform cutaneous respiration in water by diffusion through the skin. On land, respiration occurs through the buccal cavity, skin and lungs. Pulmonary respiration involves a pair of pink, elongated, sac-like lungs.
Question 15 of 101
📘 CLASS XI
Consider the following statements regarding pulmonary respiration and seasonal breathing:
I. Lungs are located in the lower abdominal region of the trunk cavity. II. Air enters through the nostrils into the buccal cavity and then passes to the lungs. III. Gaseous exchange during aestivation and hibernation takes place through the lungs. IV. The skin of the frog is highly vascularized, allowing it to function as a respiratory surface.
Explanation: Statement I is incorrect because the lungs are located in the upper part of the trunk region. Statement II is correct because air passes from the nostrils through the buccal cavity to the lungs. Statement III is incorrect because respiration during aestivation and hibernation occurs through the skin. Statement IV is correct because the highly vascular skin functions as a respiratory surface.
Question 16 of 101
📘 CLASS XI
Consider the following statements regarding the blood vascular and lymphatic systems of frogs:
I. The vascular system of the frog is of a well-developed, closed type. II. The blood vascular system involves the heart, blood vessels, and blood, while the lymphatic system consists of lymph, lymph channels, and lymph nodes. III. The heart is a muscular three-chambered organ consisting of two atria and one ventricle. IV. The heart is covered by a protective membrane called the pericardium.
Explanation: All four statements are correct. Frogs possess a closed circulatory system. The blood vascular system includes the heart, blood vessels and blood, whereas the lymphatic system consists of lymph, lymph channels and lymph nodes. The heart is three-chambered with two atria and one ventricle and is enclosed by the pericardium.
Question 17 of 101
📘 CLASS XI
Analyze the following statements regarding cardiac structures and circulation pathways in frogs:
I. A triangular structure called sinus venosus joins the left atrium of the heart. II. Sinus venosus receives deoxygenated blood through the major veins called vena cava. III. The ventricle opens into a sac-like conus arteriosus on the dorsal side of the heart. IV. Blood from the heart is carried to all parts of the body by the arteries.
Explanation: Statement I is incorrect because the sinus venosus joins the right atrium. Statement II is correct because it receives blood through the venae cavae. Statement III is incorrect because the conus arteriosus arises from the ventral side of the ventricle. Statement IV is correct because arteries carry blood from the heart to the body.
Question 18 of 101
📘 CLASS XI
Consider the following statements regarding portal systems in frogs:
I. The hepatic portal system is a special venous connection between the kidneys and lower parts of the body. II. The renal portal system is a special venous connection between the kidneys and lower parts of the body. III. Special venous connections exist in frogs between the liver and the intestine. IV. The veins collect blood from different parts of the body to the heart, forming the venous system.
Explanation: Statement I is incorrect because the hepatic portal system connects the liver and intestine. Statement II is correct because the renal portal system connects the kidneys with the lower parts of the body. Statement III is correct because the hepatic portal system links the intestine and liver. Statement IV is correct because veins return blood from the body to the heart.
Question 19 of 101
📘 CLASS XI
Consider the following statements regarding the composition of blood and lymph in frogs:
I. Blood is composed of plasma and blood cells. II. Blood cells include nucleated erythrocytes (RBCs), leucocytes (WBCs), and platelets. III. RBCs contain the red coloured pigment haemoglobin. IV. Lymph is identical to blood, containing the same proteins and RBC count.
Explanation: Statements I, II and III are correct because frog blood contains plasma, nucleated erythrocytes, leucocytes and platelets, with haemoglobin present in RBCs. Statement IV is incorrect because lymph lacks RBCs and contains fewer proteins than blood.
Question 20 of 101
📘 CLASS XI
Analyze the statements regarding blood circulation and physiology:
I. Blood carries nutrients, gases, and water to respective sites during circulation. II. Pumping action of the muscular heart achieves blood circulation. III. The frog's circulatory system exhibits a double circulation pattern. IV. Lymph carries a high concentration of erythrocytes compared to blood.
Explanation: Statement I is correct because blood transports nutrients, respiratory gases and water throughout the body. Statement II is correct because circulation is maintained by the pumping action of the muscular heart. Statement III is incorrect because the source describes the frog as having a closed circulatory system with single circulation. Statement IV is incorrect because lymph lacks erythrocytes (RBCs).
