100 Questions on Zoology Part-1 – Answered

1. Why is amoeba called acellular?

Because the entire body is made up of a single cell and all the vital functions are performed by it.

2. Define a tissue?


A group of cells having identical structure, function and origin.

3. What is a simple tissue?

In a simple tissue there will be only one kind of cells.

4. What is a complex tissue?


A complex tissue has more than one kind of cells.

5. What is histology?

Histology deals with the study of tissues.

6. What is an epithelial tissue?


It may be defined as a tissue composed of one or more layers of cells covering the external or internal surface of the body or may be embryologically derived from such a surface.

7. What is a basement membrane?

The delicate non cellular, gelatinous membrane on which the epithelial cells rest is called the basement membrane.

8. Which tissue lines the interior of blood vessels?


Endothelium lines the interior of the blood vessels.

9. What is germinal epithelium?

Germinal epithelium helps in the production of egg sperm cells.

10. Name the different types of simple epithelium?


Simple squamous epithelium, cuboidal epithelium, columnar epithe Hum and ciliated epithelium.

11. What is a brush bordered epithelium?

The cells of cuboidal epithelium which have numerous fingers like projections are referred to as brush bordered epithelium.

12. What are microvilli?


The finger like projections produced from the cuboidal cells or urinary tubules are called microvilli.

13. Name any two places where cuboidal epithelium is present?

Thyroid follicles, urinary tubules etc.

14. Which tissue is found in the inner lining of the Bowmann’s capsule?

Simple squamous epithelium.

15. Name the tissue that is found in the alveoli of lungs?

Simple squamous epithelium.

16. What is the name of projections found in the urinary tubules?


17. Where do you find germinal epithelium?

In reproductive organs.

18. What are goblet cells?

The mucus secreting cells present between the columunar epithelium cells that line the stomach and the intestine are called goblet cells.

19. What is the secretion of goblet cells?


20. Where do you find goblet cells?

Present between the columnar epithelium cells of the lining of stomach and intestine.

21. What is a mucous membrane?

The epithelial tissue containing the mucus secreting cells along with the underlying supporting connective tissue is called the mucous membrane.

22. What is the function of microvilli in small intestine?

They help in the absorption of water and digested food.

23. Name the projections found in the inner wall of small intestine?


24. What is a cilium?

Thin elongated cytoplasmic process coming out of the epithelium is called a cilium.

25. What is the function of cilia found in epithelial cells?

The cilia have beating action as a result of which the mucus and other substances are transferred over the epithelium from one place to another.

26. What is a glandular epithelium?

These are epithelial cells specialised for the secretion of chemical sub stances like mucus, enzymes or hormones.

27. Which are the two basic types of glandular epithelium?

Unicellular glands and multicellular glands.

28. Which are the two types of multicellular glands?

Tubular glands and secular glands.

29. Name any one unicellular gland?

Goblet cells.

30. What is a tubular gland?

They are tubular in appearance and are the modifications of glandular epithelium.

31. How many types of tubular glands are found?

Two types, simple tubular glands and compound tubular glands.

32. Which gland is found in the nuptial pad of male frogs?

Simple straight tubular glands.

33. What type of glands are the milk glands in mammals?

Compound tubular glands.

34. What is a saccular gland?

These glands are flask shaped in appearance and have a wide secretary part called the alveolus.

35. What are the types of alveolar glands?

Simple alveolar glands and compound alveolar glands.

36. Classify the glands based on the mode of release of secretion?

Exocrine, endocrine and heterocrine.

37. What is the other name for endocrine glands?

Ductless glands.

38. Where do the endocrine glands release their secretion?

They release their secretion directly to the blood stream.

39. Why endocrine glands are called ductless glands?

Because they release their secretion directly into the blood stream and are carried to the site of action along with the blood.

40. What is a heterocrine gland?

It combines the characters of both endocrine and exocrine glands in that the secretion is first released by way of duct and the product then is directly carried into the blood.

41. Name one difference between simple squamous and stratified squamous epithelium?

Simple squamous is made up of a single layer of cells while stratified squamous epithelium is made up of several layers of cells.

42. What is Keratin?

Kertain is a water proof protein presents the stratified squamous epithelium.

43. What is Karnification?

The process of replacement of cytoplasm with keratin is called karnification.

44. Where do you find in human body the nonkeratinized epithelium?

In the buccal cavity, pharynx and oesophagus.

45. Which germ layer gives rise to connective tissue?


46. Name any one function of a connective tissue?

It binds other tissues together providing support.

47. Name the types of connective tissue?

Connective tissue proper, skeletal tissue and fluid tissue.

48. Name the types of connective tissue proper?

Arolar tissue, fibrous tissue and adipose tissue.

49. Which is the most widely distributed connective tissue proper in animals?

Arolar tissue.

50. Name the fibres found in Arolar tissue?

White fibres and yellow fibres.

51. What is elastin?

This is a protein found in the yellow fibres of the Arolar tissue.

52. Name the cells found in the matrix of areolar tissue?

Fibro blast or fibro cytes, macrophages or histocytes and mast cells.

53. What is the name given to the space between the fibres in an areolar tissue?


54. What are macrophages?

These are cells found in the matrix of the Arolar tissue.

55. Where do you find fibroblasts?

These are found in the aerolar tissue.

56. What are the secretions of mast?

These cells produce harapine, histamine and serotonin.

57. What is an adipose tissue?

It is mainly concerned the storage of fat. It is one of the connective tissues.

58. Which substance is stored in adipose tissue?


59. Which are the two types of fibrous tissue?

White fibrous tissue and yellow elastic tissue.

60. What is the name given to the cords of white fibrous tissue?


61. What is the name given to the cords of yellow elastic tissue?


62. Name any one difference between a tendon and a ligament?

Tendon is composed of white fibrous tissue whereas ligament is com posed of yellow elastic tissue.

63 Which are the two types of skeletal tissue?

Cartilage and bone.

64. Name the types of cartilages?

Hyaline cartilage, fibrous cartilage and calcified cartilage.

65. What is chondrin?

The intercellular matrix present in the cartilage is called chondrin.

66. What are chondroblasts?

The cartilage cells embedded in the matrix are called chondroblasts.

67. Why it takes a long time for healing of cartilage injury?

Because there is no blood supply.

68. What is perichondrium?

The stiff sheath that binds the cartilage externally is called the perichondrium.

69. Name some organs where hyaline cartilage is found?

Tracheid, bronchial rings, larynx, nasal septum, stermal ribs etc.

70. Why some cartilages are called calcified cartilages?

Because of the deposition of calcium salts in the matrix the cartilages are called calcified cartilages.

71. What is collagen?

Hard non elastic fibres present in the matrix of calcified cartilage are known as collagen.

72. Name the three main regions in the bone which surround the central cavity?

These regions are periosteum, matrix and endosteum.

73. What is ossein?

The compound which is deposited to form the bones is called ossein.

74. What is a Haversian canal?

The narrow longitudinal cavities present within the matrix of the bones are called haversian canal.

75. What is a Haversian system?

The haversian canals together with lamellae, lacunae and canaliculi forms a haversian system.

76. What is a Haversian lamellae?

The layers found within the matrix of the bone are called haversian lamellae.

77. What are bone lacunae?

Small fluid spaces found within the lamellae of the bones are called bone lacunae.

78. What are canaliculi (in bones)?

The fine radiating canals that are given off from bone lacunae are called canaliculi.

79. What are Volkmann’s canals?

Small transverse canals which connect the haversian canals are called the Volkmann’s canals.

80. What is an osteocyte?

The bone cell present in lacuna is called an osteocyte.

81. What is periosteum?

The region that surrounds the central cavity of the bone is called periosteum.

82. What is endosteum?

This is found external to the bone marrow cavity and is made up of white fibrous tissue.

83. Define ossification?

The process of bone formation is called ossification.

84. What is the main difference between the frog bone and a mammalian bone?

In the case of frog bone the lamellae are concentrically arranged around the bone marrow cavity. In the case of mammals the lamellae surrounds the haversian canals.

85. Name the two types of fluid connective tissue?

Blood and lymph.

86. Why is blood called a tissue even though it is a fluid?

Because it has a number of cells and the cells are present in a liquid matrix.

87. What is the average quantity of blood found in a human adult?

6.8 litres.

88. What is plasma?

The fluid portion of the blood is called plasma.

89. Name the two basic types of blood cells?

Corpuscles and platelets.

90. Name the two types of blood corpuscles?

Erythrocytes and leucocytes.

91. What are megaloblasts?

The cells present in bone marrow which form the RBC’s are called megaloblasts.

92. Which is the site ofproduction of blood cells?

Bone marrow.

93. Which pigment imparts colour to RBCs?


94. What is haemoglobin chemically?

It is a conjugated protein.

95. What is erythropoieusis?

The process of the formation of RBC’s is called erythropoieusis.

96. What is phagocytosis?

The process of absorption of foreign particles by leucocytes is called phagocytosis.

97. What is leucopoieusis?

The process of formation of leucocytes is known as leucopoieusis.

98. What is the other name for WBCs?


99. What is the average life span of RBCs?

120 days.

100. Name the two basic types of leucocytes?

Agrangulocytes and granulocytes.