Q1. Which one of the following has an open circulatory system?
- 1) Periplaneta
- 2) Pheretima
- 3) Hirudinaria
- 4) Octopus
Periplaneta (cockroach) shows the presence of the open circulatory system. Its body cavity and viscera are bathed by blood. 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.
Q2. In earthworm,
- 1) Pharyngeal and septal nephridia are enteronephric.
- 2) Integumentary and septal nephridia are enteronephric.
- 3) Pharyngeal and septal nephridia are exonephric.
- 4) Integumentary and pharyngeal nephridia are exonephric.
In earthworm, the pharyngeal and septal nephridia are enteronephric, while the integumentary nephridia are exonephric.
Q3. Which one of the following is present in the integument of frog but not in that of mammals?
- 1) Sweat glands
- 2) Dermis
- 3) Stratum germinativum
- 4) Mucous gland
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.
Q4. Simple epithelium is a tissue in which the cells are
- 1) Loosely connected to one another to form an irregular organ
- 2) Continuously dividing to provide form to an organ
- 3) Hardened and provide support to the organ
- 4) Cemented directly to one another to form a single layer
An epithelium is a sheet or tube of firmly adherent cells with minimum material and space between them.
Q5. Which structure is absent in male cockroach?
- 1) Labium
- 2) Phallomere
- 3) Spermatheca
- 4) None of the above
Spermathecae are present in female cockroaches. A pair of spermathecae is present in the 6th segment which opens into the genital chamber. Sperms are received and stored in the spermatheca.
Q6. Compared to those of humans, the erythrocytes in frog are
- 1) Nucleated and without haemoglobin
- 2) Without nucleus but with haemoglobin
- 3) Nucleated and with haemoglobin
- 4) Much smaller and fewer
Erythrocytes of frogs are nucleated and carry haemoglobin. Even birds have nucleated erythrocytes. Mammals, except camels, have enucleated erythrocytes.
Q7. State one difference between the nymph and adult cockroach.
The nymph bears wing pads in all stages, while the adult cockroach has wings.
Q8. State the scientific term used for the tongue of cockroach.
Q9. Write the functions of the compound epithelium.
Functions of compound epithelium: It provides protection against chemical and mechanical stresses. It covers the dry surface of the skin as well as the moist surface of the buccal cavity, pharynx, inner lining of ducts of salivary glands and pancreatic ducts.
Q10. Write the name of the frog species which is common in India.
Rana tigrina is commonly found in India.
Q11. In a cockroach, the abdomen consists of how many segments?
The abdomen of cockroach consists of ten segments.
Q12. Differentiate between loose connective tissue and dense connective tissue.
Loose Connective Tissue Dense Connective Tissue 1. Cells and fibres are arranged loosely in a semi-fluid ground substance. 1. Fibres and fibroblasts are compactly arranged. 2. Areolar tissue provides the support framework for epithelium. 2. Tendons attach skeletal muscles to bones. 3. Adipose tissue is specialised to store fats. 3. Ligaments help to attach one bone to another.
Q13. Name the organ which secretes digestive juices in cockroach.
Gastric caecae (hepatic caecae) secrete digestive juices in cockroach.
Q14. Which set clearly indicates striated muscles?
- 1) Spindle, unbranched and uninucleated
- 2) Cylindrical, striped and branched
- 3) Cylindrical, syncytial and unbranched
- 4) Cylindrical, striped and nucleated
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.
Q15. If a live earthworm is pricked with a needle on its outer surface without damaging its gut, then the fluid which comes out is
- 1) Haemolymph
- 2) Excretory fluid
- 3) Coelomic fluid
- 4) Slimy mucus
The schizocoel of earthworm, i.e. the cavity between the body wall and the alimentary canal, is filled with coelomic fluid. It is a milky white alkaline fluid which helps in protection and locomotion.
Q16. Which of the following is absent from the coelomic fluid of earthworm?
- 1) Proteins
- 2) Salts
- 3) Haemoglobin
- 4) Corpuscles
The coelomic fluid in earthworm is water plasma which contains proteins, salts and corpuscles (viz. phagocytes, leucocytes, mucocytes and eleocytes).
Q17. Select the correct statement from the ones given below with respect to Periplaneta americana.
- 1) There are 16 long Malpighian tubules present at the junctions of the midgut and hindgut.
- 2) Grinding of food is carried out only by the mouth parts.
- 3) The nervous system located dorsally consists of segmentally arranged ganglia joined by a pair of longitudinal connectives.
- 4) Males bear a pair of short thread-like anal styles.
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.
Q18. Define vermicomposting.
The process of increasing the fertility of soil by earthworms is called vermicomposting.
Q19. Distinguish between simple epithelium and compound epithelium.
Simple Epithelium Compound Epithelium 1. It is composed of a single layer of cells. 1. It is composed of more than one layer of cells. 2. It is involved in functions such as diffusion, secretion, absorption etc. 2. It is involved in the protection of the skin and inner linings of the organs.
Q20. Name the structures other than the Malpighian tubules which help in excretion in cockroach.
Besides the Malpighian tubules, nephrocytes, the fat body and urecose glands help in excretion in cockroaches.
Q21. What is the meaning of paurometabolous development?
The development through the nymphal stages is called paurometabolous development.
Q22. Ovaries in frog are attached to the
- 1) Both B and C
- 2) Dorsal wall of the kidneys
- 3) Posterior wall of the abdomen
- 4) Dorsal wall of the abdomen
The ovaries are attached to the dorsal wall of the abdomen and kidneys by a thin membrane known as mesovarium.
Q23. Which one of the following structures in Pheretima is correctly matched with its function?
- 1) Typhlosole – Storage of extra nutrients
- 2) Setae – Defence against predators
- 3) Clitellum – Secretes cocoon
- 4) Gizzard – Absorbs digested food
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
Q24. One special feature in earthworm, Pheretima, is that
- 1) The S-shaped setae embedded in the integument are the defensive weapons used against the enemies.
- 2) The typhlosole greatly increases the effective absorption area of the digested food in the intestine.
- 3) Fertilisation of eggs occurs inside the body.
- 4) It has a long dorsal tubular heart.
The typhlosole is the median fold of the dorsal wall of the intestine between segments 26 and 35. It increases the area of absorption.
Q25. Define oothecae.
Oothecae are dark reddish to brown colour capsules which enclose or encase the fertilised eggs in cockroaches.
Q26. Write the names of three junctions found in the epithelium.
Three junctions found in the epithelium are 1. Tight junctions 2. Adhering junctions 3. Gap junctions
Q27. Name the cavities in bone tissues in which osteocytes are placed.
Q28. Identify the connective tissue: (a) Provides a structural framework to the body (b) Transports various substances in the human body (c) Supports the framework for epithelium (d) Attaches skeletal muscles to bones
(a) Provides structural framework to the body – Bones (b) Transports various substances in the human body – Blood (c) Supports the framework for epithelium – Areolar tissue (d) Attaches skeletal muscles to bones – Tendons
Q29. Epithelial cells of the intestine involved in food absorption have on their surface:
- 1) Pinocytic vesicles
- 2) Zymogen granules
- 3) Microvilli
- 4) Phagocytic vesicles
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.
Q30. The colour of the body in earthworm is brown due to the presence of
- 1) Haemocyanin
- 2) Blood
- 3) Haemoglobin
- 4) Porphyrin
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.
Q31. Name the membrane which protects the eyes while the frog is in water.
The nictitating membrane protects the eyes while the frog is in water.
Q32. Which one of the following is not syncytial?
- 1) Skeletal muscle
- 2) Smooth muscle
- 3) Interstitial muscle
- 4) Cardiac muscle
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.
Q33. Stratum germinativum is an example of which kind of epithelium?
- 1) Ciliated
- 2) Columnar
- 3) Squamous
- 4) Cuboidal
Stratum germinativum consists of columnar cells resting on a common basement membrane.
Q34. State the difference between dense regular connective tissue and dense irregular connective tissue on the basis of arrangement of fibres.
Dense Regular Connective Tissue Dense Irregular Connective Tissue Collagen fibres are present in rows between many parallel bundles of fibres. Fibroblasts and collagen fibres are oriented differently.
Q35. Which of the following animals is unisexual?
- 1) Earthworm
- 2) Tapeworm
- 3) Cockroach
- 4) Sponge
- 5) Leech
Cockroaches are unisexual, i.e. the sexes are separate. They are also called dioecious. Leech, sponges and earthworm are hermaphrodites.
Q37. Name the acid which is found in humans and is neutralised by the calciferous glands of earthworms.
Q37. Pheretima and its close relatives derive nourishment from
- 1) Decaying fallen leaves and soil organic matter
- 2) Sugarcane roots
- 3) Soil insects
- 4) Small pieces of fresh fallen leaves of maize etc.
Earthworm derives its nourishment from decaying fallen leaves and soil organic matter. The gizzard grinds the decaying matter.
Q38. The salivary gland in earthworm is found in
- 1) Ventral wall of buccal cavity
- 2) Pharyngeal wall
- 3) Dorsal wall of buccal cavity
- 4) None of the above
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.
Q39. Haversian canal occurs in
- 1) Humerus
- 2) Clavicle
- 3) Scapula
- 4) Pubis
The Haversian system is found in the long bones of mammals and absent in the spongy bones of mammals.
Q40. State the function of nephridia.
Nephridia regulate the volume and composition of the body fluids in earthworm.
Q41. Name the structure which represents or acts as the brain in cockroach.
Supraoesophageal ganglion acts as the brain in cockroach.
Q42. Antennae of cockroach function as
- 1) Auditory receptors
- 2) Olfactory receptors
- 3) Tactile and olfactory receptors
- 4) Gustatory receptors
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.
Q43. What are the three parts of the thorax of a cockroach?
The three parts of the thorax of a cockroach are prothorax, mesothorax and metathorax.
Q44. What is present at the junction of the midgut and hindgut? State its function.
At the junction of the midgut and hindgut, a ring of 100-150 yellow coloured Malpighian tubules are present. They absorb nitrogenous waste products from the haemolymph and convert them into the excretory product, i.e. uric acid.
Q45. Which one of the following is the true description about an animal concerned?
- 1) Earthworm – The alimentary canal consists of a sequence of pharynx, oesophagus, stomach, gizzard and intestine
- 2) Cockroach – 10 pairs of spiracles (2 pairs on thorax and 8 pairs on abdomen)
- 3) Frog – Body divisible into three regions – head, neck and trunk
- 4) Rat – Left kidney slightly higher in position than the right one
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.
Q46. Describe the typical skeletal muscle. State any one part of the body where skeletal muscles are found.
Typical skeletal muscle fibres are striated, bundle together and are parallel. The several bundles are further enclosed in a tough sheath of connective tissue. Skeletal muscles are found in the hands (e.g. biceps).
Q47. Name the fibrils present in the muscle tissue.
Q48. State the significance of elastin in connective tissues.
Elastin provides strength, flexibility and elasticity to the connective tissue.
Q49. Write the scientific name for cockroach.
The scientific name for cockroach is Periplaneta americana.
Q50. Name the regions in which the body of an earthworm is divided.
The body of an earthworm is divided into preclitellar, clitellar and post-clitellar regions.
Q51. Write the function of Malpighian tubules in cockroach.
In cockroach, the Malpighian tubules absorb nitrogenous waste products from the haemolymph and convert them into uric acid for excretion.
Q52. What is the function of antennae in cockroaches?
Antennae in cockroaches have sensory receptors which help in monitoring the environment.
Q53. Earthworms have no skeleton, but during burrowing, the anterior end becomes turgid and acts as a hydraulic skeleton. This is due to
- 1) Setae
- 2) Blood
- 3) Gut peristalsis
- 4) Coelomic fluid
Coelomic fluid serves as a hydrostatic skeleton and helps the muscles of the body wall in locomotion. When the circular muscles contract, the coelomic fluid provides stiffness to the body and the longitudinal muscles relax. When the earthworm holds the ground firmly, the circular muscles relax and the longitudinal muscles contract. Here, the coelomic fluid makes the region stiff which is behind the anterior region so that muscles can push the body forward.
Q54. How many ova are laid by a mature female frog at a time?
2500 to 3000 ova are laid by the female frog at a time.
Q55. What are spermatophores?
Spermatophores are bundles of sperms glued together.
Q56. Uric acid is the chief nitrogenous component of the excretory product of
- 1) Frog
- 2) Man
- 3) Earthworm
- 4) Cockroach
Uricotelic animals excrete nitrogenous waste in the form of uric acid. The excreta is in the form of a thick pellet to minimise water loss. Reptiles, birds, insects and land snails are uricotelic animals. Cockroach is an insect and hence exhibits uricotelism.
Q57. In which one of the following organisms, is its excretory organs correctly stated?
- 1) Cockroach – Malpighian tubules and enteric caeca
- 2) Humans – Kidneys, sebaceous glands and tear glands
- 3) Earthworm – Pharyngeal, integumentary and septal nephridia
- 4) Frog – Kidneys, skin and buccal epithelium
In earthworms, three pairs of pharyngeal nephridia are present in the 3rd, 4th and 5th segments. Integumentary nephridia are present in the linings of the body wall from the 3rd 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.
Q58. What is clitellum?
Clitellum is a prominent dark band of glandular tissue which covers 14-16 segments in a mature earthworm.
Q59. 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?
- 1) Neurons
- 2) Liver cells
- 3) Malpighian layer of the skin
- 4) Osteocytes
Neurons are the only cells in the body which do not divide and cannot be replaced.
Q60. Name the respiratory organ in earthworm.
A moist skin surface is the respiratory organ of the earthworm.
Q61. Identify the type of epithelium: (a) Single layer of tall and slender cells (b) Unicellular columnar cells specialised in secretion
(a) Single layer of tall and slender cells – Columnar epithelium (b) Unicellular columnar cells specialised in secretion – Unicellular glandular epithelium
Q62. In earthworm, the characteristic internal medial fold of the dorsal wall of the intestine (called typhlosole) is present in
- 1) 15 to last segment
- 2) 35 to last segment
- 3) 5 to 9 segments
- 4) 26 to 35 segments
- 5) 9 to 14 segments
Typhlosole is the median fold of the dorsal wall of the intestine between segments 26 and 35. It increases the area of absorption.
Q63. Mention any four sites in the human body where cartilage is found.
Cartilage is found in the human body at the following four sites – Outer ear joints, tip of the nose, between adjacent vertebrae and between adjacent bones in the hands and legs.
Q64. State the names of two common Indian earthworms.
Pheretima and Lumbricus
Q65. Which of the following is not exclusively supplied with involuntary muscles?
- 1) Muscular coats of blood vessels
- 2) Muscles of iris
- 3) Muscles of urethra
- 4) Muscles of the ducts of glands
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.
Q66. What are the three types of simple epithelium on the basis of structural modification?
The three types of simple epithelium on the basis of the structural modification are 1. Squamous epithelium 2. Cuboidal epithelium 3. Columnar epithelium
Q67. The female genital pore of Pheretima posthuma is located on which segment?
- 1) 14th
- 2) 15th
- 3) 16th
- 4) 18th
The female genital pore of Pheretima posthuma is located on the 14th segment. Ovarian funnels present beneath the ovaries which continue into the oviduct and join open outside as the female genital pore.
Q68. If the head of a cockroach is cut off, it remains alive for one week. Justify.
In cockroaches, a small part of the nervous system is present in the head region. The rest of the nervous system is situated on the ventral side of the body. Hence, if the head of a cockroach is cut off, it remains alive for one week.
Q69. Which of the following is absent in frog?
- 1) Sense capsules
- 2) Ribs
- 3) Cranium
- 4) Spinal cord
Ribs are absent in frog.
Q70. Write the functions of bones.
Functions of bones: They serve as the main tissue in providing a support framework to the body. They support and protect the softer tissues and organs in the body. The limb bones bear the weight of the body. The limb bones interact with the skeletal muscles attached to them to bring about movements in the body. The bone marrow serves as the site of production of blood cells. (Write any four)
Q71. Differentiate between unicellular and multicellular glandular epithelium.
Unicellular Glandular Epithelium Multicellular Glandular Epithelium 1. Made of isolated glandular cells. 1. Consists of a cluster of cells. 2. Example: Goblet cells of the alimentary canal 2. Example: Salivary glands
Q72. Name the structure which is found between 26 and 35 segments in the intestine of earthworm.
Q73. What is the composition of haemolymph?
The haemolymph is composed of plasma and haemocytes.
Q74. How does the gizzard help in grinding the food in cockroach?
The gizzard has an outer layer of thick circular muscles and a thick inner cuticle which together form six chitinous plates called teeth. These teeth help in grinding food.
Q75. Define tissue.
The tissue is a group of similar cells along with intercellular spaces which perform the same function.
Q76. Histamine-secreting cells are found in
- 1) Muscular tissue
- 2) Lungs
- 3) Nervous tissue
- 4) Connective tissue
Histamine is secreted by mast cells which are modified basophils of blood which occur in the loose connective tissue.
Q77. Write the name of organs where the smooth muscles are formed.
Smooth muscles are formed in blood vessels, intestines and stomach.
Q78. Write the name of the sclerites which cover the body of cockroach dorsally.
Q79. The heart of cockroach is
- 1) 13-chambered
- 2) 9-chambered
- 3) 29-chambered
- 4) 6-chambered
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.
Q80. Name the connective tissue in which collagen is absent.
Q81. How many Malpighian tubules are present in cockroach?
100-150 Malpighian tubules are present in cockroach.
Q82. Name one epithelial tissue in which the nuclei are located at the base of cells.
Q83. The element found in the red pigment of vertebrate blood is
- 1) Copper
- 2) Iron
- 3) Calcium
- 4) Magnesium
Haemoglobin is a conjugated protein composed of a protein called globin and an Fe2+ porphyrin complex called haeme. The mineral present in the red pigment is iron.
Q84. State the name of connective tissues.
The various connective tissues are cartilage, bone, blood and adipose tissue.
Q85. In which segment in earthworm is the clitellum present?
- 1) 14-16th segment
- 2) 16th segment
- 3) 17-19th segment
- 4) 5-6th segment
Clitellum is a dark band of the glandular tissue which is present in 14-16th segments.
Q86. Distinguish between smooth muscles and cardiac muscles.
Smooth Muscles Cardiac Muscles 1. Striations are absent. 1. Striations are present. 2. Cell junctions hold the muscle fibres together and they are bundled together in a sheath of connective tissue. 2. Cell junctions fuse the plasma membrane of muscle fibres and make them stick together. 3. They are found in the walls of internal organs such as blood vessels, stomach and intestines. 3. Cardiac muscles are present in the heart.
Q87. State the function of the simple epithelium.
The function of the simple epithelium is to line the body cavities, ducts and tubes.
Q88. What is another term used for the gizzard of cockroach?
Q89. Name the membrane which joins the dorsal tergites and the ventral sternites in cockroaches.
The arthrodial membrane which is thin, flexible and articular connects the dorsal tergites and the ventral sternites in cockroaches.
Q90. What is mesorchium?
Mesorchium is the double fold of peritoneum through which a pair of testes is adhered to the upper part of the kidneys in frogs.
Q91. What is cloaca?
Cloaca is a small median chamber which is used to pass the faecal matter, urine and sperms to the exterior.
Q92. Name the fluid connective tissue.
Q93. The hindbrain of frog comprises
- 1) Cerebellum and medulla oblongata
- 2) Both A and C
- 3) Diencephalon and cerebellum
- 4) Cerebrum and medulla oblongata
The hindbrain of frog comprises the cerebellum and medulla oblongata.
Q94. State the name of the space into which the blood vessels open in cockroaches.
Q95. Cockroaches are not of economic importance. Justify. Or Cockroaches are serious pests and vectors of several diseases. Justify.
Human homes are the habitats of cockroaches. Cockroaches thrive in and around human homes. They are pests because they contaminate food by their excreta and destroy it. Through contamination of food, cockroaches also transmit various bacterial diseases.
Q96. What is the scientific term used for the cells of cartilage?
The scientific term used for the cells of cartilage is chondrocytes.
Q97. How many times a nymph moults in order to attain the adult stage of cockroach?
A nymph moults about 13 times to attain the adult stage of cockroach.
Q98. State the name of the plates which form the exoskeleton in cockroach.
Sclerites are the hard chitinous plates which form the exoskeleton in cockroach.
Q99. State any two examples of dense connective tissue.
Tendons and ligaments are examples of dense connective tissue.
Q100. Write the name of the sclerites which cover the body of cockroach ventrally.
Q101. Distinguish between the abdomens of the male and female cockroach.
Abdomen of Male Cockroach Abdomen of Female Cockroach The genital pouch lies at the hind end of the abdomen. It is bounded dorsally by 9th and 10th terga and ventrally by the 9th sternum. The genital pouch is formed when the 7th sternum fuses with the 8th and 9th sterna. A pair of short, thread-like anal styles is present. Anal styles are absent. It contains dorsal anus, male genital pore and gonapophysis. It contains female gonopore, spermathecal pores and collateral glands.
Q102. State four types of animal tissues.
Four types of animal tissues are Epidermal tissue Connective tissue Muscular tissue Neural tissue
Q103. Name the phylum and class to which frog belongs.
Frog belongs to the phylum Chordata and class Amphibia.
Q104. What is the function of the neuroglial cell?
The function of the neuroglial cell is to protect and support neurons.
Q105. Distinguish between cartilage and bones.
Cartilage Bones 1. It is solid and pliable. 1. They are hard and non-pliable. 2. The cells are called chondrocytes. 2. The cells are called osteocytes. 3. Cartilage resists compression. 3. They provide a frame work to the body.
Q106. Explain nocturnal vision in cockroaches.
Each compound eye of cockroach is made of 2000 ommatidia. With ommatidia, a cockroach can receive several images of an object. Cockroach vision is sensitive but provides less resolution. Such vision is called mosaic vision. This kind of vision is common during the night, and hence, it is also called nocturnal vision.
Q107. Where are the spermathecal apertures located on the body of the earthworm?
Spermathecal apertures are located on the ventrolateral sides of the intersegmental grooves of 5th to 9th segments.
Q108. What are spiracles?
Spiracles are the small openings on the lateral sides of the body of cockroach though which the tracheae open outside.
Q109. Write any four sensory organs present in cockroach.
Sensory organs found in cockroach are 1. Antennae 2. Maxillary palps 3. Compound eyes 4. Labial palps 5. Anal cerci (Write any four)
Q110. What is a phallomere?
Phallomere is a chitinous asymmetrical structure which acts as the external male genitalia which surrounds the male gonopore.
Q111. State the significance of the typhlosole in earthworm.
The typhlosole increases the area of absorption in the intestine of earthworm.
Q112. Where is the squamous epithelium found?
The squamous epithelium is found in the walls of blood vessels and air sacs of the lungs.
Q113. Give an account of three different types of simple epithelia.
Three major types of simple epithelia are 1) Squamous epithelium: Cells are flattened with irregular bodies. It is found in the walls of blood vessels and the air sacs of the lungs. Its function is forming diffusion boundaries. 2) Cuboidal epithelium: Cells are cube-like and arranged in a single line.
The cuboidal epithelium is commonly found in the ducts of glands, and the tubular parts of the kidneys are nephrons. 3) Columnar epithelium: Cells are tall and slender and arranged in a single line. The nuclei of these cells are located at the base.
Columnar epithelium is found in the lining of the stomach and intestine. It aids in secretion and absorption. In some cases, the free ends of cells possess microvilli. Such epithelium is called ciliated epithelium. The epithelium is responsible for the movement of mucus and particles in a specific direction.
Q114. What is present at the junction of the foregut and midgut? State its function.
Gastric or hepatic caecae are present at the junction of the foregut and midgut. They secrete digestive juices.
Q115. Describe the adipose tissue and its functions.
Adipose tissue is an example of loose connective tissue. It is located beneath the skin. Its cells are specialised to store fat. The excess of nutrients which are not required by the body immediately are converted into fats and stored in adipose tissue.
Q116. Describe the respiratory system of cockroach.
The respiratory system of cockroach consists of a network of tracheae. Tracheae open outside through 10 pairs of spiracles which are present on the lateral side of the body. Tracheae are further divided into tracheoles which carry oxygen to all parts of the body. Exchange of gases occurs at the tracheoles by diffusion. The openings of spiracles are regulated by the sphincters.
Q117. State the function of the muscular gizzard in earthworm.
The muscular gizzard in earthworm helps in grinding the soil particles and decaying leaves.
Q118. What is the length of an adult Periplaneta americana?
The length of an adult Periplaneta americana is 34-53 mm.
Q119. How are earthworms traced in gardens?
Earthworms are traced by their faecal matter called worm casting in gardens.
Q120. Name one gland which shows the presence of multicellular glandular epithelium with cluster of cells.
Q121. Name the type of muscle tissue in which the fibres taper at both ends and do not show any striations.
Q122. Write the names of the mouthparts found in cockroach.
The mouthparts found in cockroach are a labrum, a pair of mandibles, a pair of maxillae and a labium.
Q123. Describe the exoskeleton of cockroach.
In cockroach, the exoskeleton is hard, chitinous and brown in colour. It is made of hardened plates called sclerites. The sclerites present on the dorsal side are called tergites, and the ones present on the ventral side are sternites. Tergites and sternites are joined to one another by a flexible, articular membrane called the arthrodial membrane.
Q124. Name the tissue which lines the inner surface of fallopian tubes.
Ciliated epithelium lines the inner surface of fallopian tubes.
Q125. Answer in one word: Membrane which joins sclerites A median flexible lobe enclosed by the mouth parts Cavity in which visceral organs are present Hexagonal units present in compound eyes
Membrane which joins sclerites – Arthrodial membrane A median flexible lobe enclosed by the mouth parts – Hypopharynx Cavity in which visceral organs are present – Haemocoel Hexagonal units present in compound eyes – Ommatidia.