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Q1. In which segment in earthworm is the clitellum present?

• 16th segment
• 17-19th segment
• 14-16th segment
• 5-6th segment

Solution

Clitellum is a dark band of the glandular tissue which is present in 14-16th segments.

Q2. Consider the following four statements (A-D) related to the common frog Rana tigrina, and select the correct option stating which ones are true (T) and which ones are false (F). Statements: A. One dry land it would die due to lack of O₂ if its mouth is forcibly kept closed for a few days. B. It has four chambered heart. C. On dry land it turns uricotelic from ureotelic. D. Its life history is carried out in pond water. options:

• (A) F, (B) F, (C) T, (D) T
• (A) F, (B) T, (C) T, (D) F
• (A) T, (B) F, (C) F, (D) T
• (A) T, (B) T, (C) F, (D) F

Solution

(A) Dry skin causes cutaneous respiration. (B) Frog has three-chambered heart. (C) Frog can never be uricotelic. (D) Because of external fertilisation in water.

Q3. Pheretima and its close relatives derive nourishment from  

• Sugarcane roots  
• Decaying fallen leaves and soil organic matter  
• Soil insects  
• Small pieces of fresh fallen leaves of maize etc.

Solution

Earthworm derives its nourishment from decaying fallen leaves and soil organic matter. The gizzard grinds the decaying matter.  

Q4. Compared to those of humans, the erythrocytes in frog are  

• Without nucleus but with haemoglobin  
• Nucleated and with haemoglobin  
• Much smaller and fewer  
• Nucleated and without haemoglobin  

Solution

Erythrocytes of frogs are nucleated and carry haemoglobin. Even birds have nucleated erythrocytes. Mammals, except camels, have enucleated erythrocytes.

Q5. Which set clearly indicates striated muscles?  

• Cylindrical, striped and nucleated  
• Cylindrical, striped and branched  
• Cylindrical, syncytial and unbranched  
• Spindle, unbranched and uninucleated  

Solution

Striated muscles are cylindrical with fibres enclosed in a connective sheath (skeletal muscles) or fused plasma membranes (cardiac muscles). They are multinucleated, and the cells do not exist independently, but their cytoplasms are fused.  

Q6. The clitellum is a distinct part in the body of earthworm. It is found in

• Segments l3-14-15
• Segments 14-15-16
• Segments 12-l3-14
• Segments 15-16-17

Solution

Clitellum is a glandular tissue present in segments 14 to 16. It is a dark band of tissue which secretes mucus and albumin. Clitellum also has a role in the formation of a cocoon.

Q7. The number of abdominal segments in male and female cockroach is

• 10, 10
• 9, 10
• 10, 11
• 8, 10
• 9, 9

Solution

There are 10 abdominal segments in male and female cockroach. The first nine segments in males and the first seven segments in females are distinct. The remaining segments are modified into external genitalia and are hidden under the last segment.

Q8. The body of earthworm is divided into how many similar segments which are called metameres or somites?

• 60-120
• 100-120
• 80-120
• 120 or more

Solution

The body of an earthworm is divided into 100-120 similar segments, i.e. metameres.

Q9. In frogs, the ventricle opens into

• Truncus
• Sinus venosus
• Left precaval
• Aortic trunks

Solution

In frogs, there are two chambers in addition to the two atria and a ventricle - sinus venosus and truncus or conus arteriosus. Sinus venosus opens into the right atrium, while the ventricle opens into the truncus.

Q10. Select the correct statement from the ones given below with respect to Periplaneta americana.

• The nervous system located dorsally consists of segmentally arranged ganglia joined by a pair of longitudinal connectives.  
• Males bear a pair of short thread-like anal styles.
• There are 16 long Malpighian tubules present at the junctions of the midgut and hindgut.
• Grinding of food is carried out only by the mouth parts.  

Solution

Males bear a pair of short thread-like anal styles. Anal styles are absent in female cockroaches. The nervous system is located on the ventral side. It consists of segmentally arranged ganglia joined by a pair of longitudinal connectives. There are 100-105 thin Malpighian tubules present at the junctions of the midgut and hindgut. The gizzard also helps in the grinding of food.

Q11. In earthworm, the characteristic internal medial fold of the dorsal wall of the intestine (called typhlosole) is present in

• 5 to 9 segments
• 9 to 14 segments
• 26 to 35 segments
• 15 to last segment
• 35 to last segment

Solution

Typhlosole is the median fold of the dorsal wall of the intestine between segments 26 and 35. It increases the area of absorption.

Q12. The anterior abdominal vein in frog is formed by the union of

• Femoral veins  
• Sciatic veins  
• Renal veins  
• Pelvic veins  

Solution

The anterior abdominal vein in frog is part of the renal portal system. It is formed by the union of two pelvic veins. The anterior abdominal vein receives blood from the urinary bladder and ventral abdominal wall and enters the liver.

Q13. Four healthy people in their twenties got involved in injuries resulting in damage and death of a few cells of the following. Which of the cells are least likely to be replaced by new cells?

• Neurons
• Liver cells
• Osteocytes
• Malpighian layer of the skin

Solution

Neurons are the only cells in the body which do not divide and cannot be replaced.

Q14. Skin is an accessory organ of respiration in

• Humans
• Frogs
• Rabbits
• Lizards

Solution

In frogs, respiration occurs in three ways. 1. Cutaneous respiration: Frogs respire through the skin. This happens during aestivation and hibernation. 2. Buccopharyngeal respiration: This occurs through the buccal cavity when the frog is out of water. 3. Pulmonary respiration: Lungs are used for respiration.

Q15. Which one of the following is not syncytial?  

• Cardiac muscle  
• Skeletal muscle  
• Smooth muscle  
• Interstitial muscle  

Solution

Smooth muscles are not striated. Each muscle fibre is with one nucleus. Many such fibres together are enclosed in a connective tissue sheath, but their cytoplasms are not fused.  

Q16. Histamine-secreting cells are found in

• Connective tissue
• Lungs
• Muscular tissue
• Nervous tissue

Solution

Histamine is secreted by mast cells which are modified basophils of blood which occur in the loose connective tissue.

Q17. _________________ is a highly specialised liquid connective tissue.

• Cartilage
• Blood
• Hormone
• Enzyme

Solution

Blood is the only liquid connective tissue. It is made of plasma and blood corpuscles and performs various functions of transporting materials, enzymes and hormones. White blood cells are involved in the defence system of the body. Blood also performs functions such as blood coagulation, phagocytosis etc.

Q18. Spermatheca in earthworm is

• For producing sperms
• For storage of sperms obtained during copulation
• Both 1 and 2 above
• None of the above

Solution

Four pairs of spermathecae are present from segments 6 to 9. There is one pair in each spermathecase. Spermathecae receive sperms from another earthworm during copulation and store them temporarily.

Q19. The cloaca in frog is a common chamber for the urinary tract, reproductive tract and

• Alimentary canal
• Portal system
• Hepatic portal vessels
• Notochord
• Lymphatic system

Solution

Cloaca is the chamber which is used to pass urine, sperms and faecal matter outside the body. Hence, it is a common chamber for the urinary tract, reproductive tract and alimentary canal.

Q20. The salivary gland in earthworm is found in

• Dorsal wall of buccal cavity
• Ventral wall of buccal cavity
• Pharyngeal wall
• None of the above

Solution

Salivary glands are bulb-like structures present in the pharyngeal walls. The ducts of the salivary glands are present in the pharyngeal epithelium. The glands secrete the salivary mucus in the pharynx.

Q21. In which one of the following organisms, is its excretory organs correctly stated?  

• Humans - Kidneys, sebaceous glands and tear glands  
• Earthworm - Pharyngeal, integumentary and septal nephridia  
• Cockroach - Malpighian tubules and enteric caeca  
• Frog - Kidneys, skin and buccal epithelium  

Solution

In earthworms, three pairs of pharyngeal nephridia are present in the 3^rd, 4^th and 5^th segments.     Integumentary nephridia are present in the linings of the body wall from the 3^rd segment to the last segment.     Septal nephridia are present on the intersegmental septa of segment 15 to the last. These nephridia open into the small intestine.  

Q22. The excretory organs of cockroach are  

• Malpighian corpuscles  
• Malpighian tubules  
• Hepatic caecae  
• Metanephridia  
• Green glands  

Solution

Malpighian tubules are thin, yellow colour filaments. About 100-1050 tubules are present at the junction of the midgut and hindgut. Malpighian tubules help in the removal of the excretory product from the haemolymph.  

Q23. Epithelial cells of the intestine involved in food absorption have on their surface:

• Pinocytic vesicles
• Phagocytic vesicles
• Zymogen granules
• Microvilli

Solution

The epithelium present in the lining of the intestine is columnar epithelium. Its cells are tall, slender and bear microvilli. Microvilli are brush-like structures which provide a larger surface area for the absorption of nutrients from the intestine.

Q24. Which structure is absent in male cockroach?  

• Labium  
• Phallomere  
• Spermatheca  
• None of the above  

Solution

Spermathecae are present in female cockroaches. A pair of spermathecae is present in the 6^th segment which opens into the genital chamber. Sperms are received and stored in the spermatheca.  

Q25. The female genital pore of Pheretima posthuma is located on which segment?

• 14th
• 16th
• 18th
• 15th

Solution

The female genital pore of Pheretima posthuma is located on the 14^th segment. Ovarian funnels present beneath the ovaries which continue into the oviduct and join open outside as the female genital pore.

Q26. Which of the following is not exclusively supplied with involuntary muscles?

• Muscular coats of blood vessels
• Muscles of the ducts of glands
• Muscles of iris
• Muscles of urethra

Solution

Smooth muscles are involuntary muscles and are found in the posterior part of the oesophagus, stomach, urinogenital tract, blood vessels, iris of eye and dermis of skin.

Q27. Which of the following is absent from the coelomic fluid of earthworm?  

• Salts  
• Haemoglobin  
• Corpuscles  
• Proteins  

Solution

The coelomic fluid in earthworm is water plasma which contains proteins, salts and corpuscles (viz. phagocytes, leucocytes, mucocytes and eleocytes).  

Q28. Bidder's canal is found in

• Testes of frog
• Kidney of frog
• Kidney of rabbit
• Both 1 and 3 above

Solution

The Bidder’s canal in frog connects the male reproductive system with the excretory system. It connects the testes via vasa efferentia to the kidneys.

Q29. Which one of the following is the true description about an animal concerned?

• Rat - Left kidney slightly higher in position than the right one
• Cockroach - 10 pairs of spiracles (2 pairs on thorax and 8 pairs on abdomen)
• Earthworm - The alimentary canal consists of a sequence of pharynx, oesophagus, stomach, gizzard and intestine
• Frog - Body divisible into three regions - head, neck and trunk

Solution

In cockroach, two pairs of spiracles are present in the thoracic region and eight pairs are present in the abdominal region. Spiracles are slit-like apertures through which air enters the body of a cockroach. In rat, the right kidney is slightly higher in position than the left kidney due to the position of the liver. In earthworm, the correct sequence of the alimentary canal is pharynx, oesophagus, gizzard, stomach and intestine. In frog, the body is divisible into the head and trunk. The neck is absent.

Q30. The hindbrain of frog comprises

• Cerebellum and medulla oblongata
• Cerebrum and medulla oblongata
• Diencephalon and cerebellum
• Both A and C

Solution

The hindbrain of frog comprises the cerebellum and medulla oblongata.

Q31. Antennae of cockroach function as  

• Tactile and olfactory receptors  
• Gustatory receptors  
• Auditory receptors  
• Olfactory receptors  

Solution

Antennae are thread-like structures which extend forward from a socket present on the head dorsally. Each antenna is made of small segments called podomeres. They are mobile and act as tactile, olfactory and thermal receptors.  

Q32. Stratum germinativum is an example of which kind of epithelium?

• Cuboidal
• Ciliated
• Columnar
• Squamous

Solution

Stratum germinativum consists of columnar cells resting on a common basement membrane.

Q33. Match the following about Cockroach, and choose the correct option.     Phallomere   Chain of developing ova   Gonopore      Bundles of sperm   Spermatophore   Opening of the ejaculatory duct   Ovarioles   External genitalia       

• A-iii, B-iv, C-ii, D-i  
• A-iv, B-iii, C-ii, D-i  
• A-iv, B-ii, C-iii, D-i  
• A-ii, B-iv, C-iii, D-i  

Solution

Phallomere   (iv) External genitalia in male cockroaches     Gonopore      (iii) Opening of the ejaculatory duct outside the body in male     Spermatophore   (ii) Bundles of sperm     Ovarioles   (i) Chain of developing ova in female cockroaches  (eight ovarioles in each ovary)        

Q34. The colour of the body in earthworm is brown due to the presence of

• Porphyrin
• Haemoglobin
• Blood
• Haemocyanin

Solution

Porphyrin is a dark red pigment which is sensitive to light. It imparts red colour to the earthworm and protects it from solar UV radiations.

Q35. Which one of the following is present in the integument of frog but not in that of mammals?

• Dermis
• Mucous gland
• Sweat glands
• Stratum germinativum

Solution

In frogs, the skin is made of epidermis and dermis. The dermis consists of mucous glands. The ducts of these glands open on the skin surface. In mammals, dermis, sweat glands and stratum germinativum are present in mammals.

Q36. Which one of the following characteristics is common in both humans and adult frogs?  

• Four-chambered heart  
• Internal fertilisation  
• Nucleated RBCs  
• Ureotelic mode of excretion  

Solution

Mammals and amphibians excrete nitrogenous wastes in the form of urea. Hence, they are called ureotelic animals. In human, fertilisation is internal, RBCs are enucleated and the heart is four-chambered. In frog, fertilisation is external, RBCs are nucleated and the heart is three-chambered.

Q37. Male and female cockroach differ due to the presence or absence of  

• Anal cerci and anal style  
• Anal cerci  
• Anal style  
• Anal setae  

Solution

In cockroaches, anal styles are thread-like structures present only in males and absent in females.  

Q38. Which one of the following structures in Pheretima is correctly matched with its function?  

• Clitellum - Secretes cocoon  
• Gizzard - Absorbs digested food  
• Setae - Defence against predators  
• Typhlosole - Storage of extra nutrients  

Solution

The clitellum is a glandular tissue present in segments 14 to 16. It secretes a substance during cocoon formation which encircles the worm. It is a dark band of tissue which secretes mucus and albumin. Gizzard - grinding of food particles Setae - help in locomotion of the earthworm Typhlosole - increases the absorption area in the intestine

Q39. The heart of cockroach is

• 13-chambered
• 29-chambered
• 9-chambered
• 6-chambered

Solution

The heart of a cockroach is a long tube-like structure. It lies along the mid-dorsal line of the thorax and abdomen. It is a 13-chambered organ, and the opening of each chamber into other chambers is guarded by valves.

Q40. Haversian canal occurs in

• Humerus
• Pubis
• Scapula
• Clavicle