CBSE Class 11 Biology Very Short Answer Questions: Structural Organisation in Animals (NCERT-Based)

Course and Examination Details

Course: CBSE Class 11 Biology

Board: Central Board of Secondary Education

Unit II: Structural Organisation in Animals and Plants

Chapter 7: Structural Organisation in Animals

Question Type: Very Short Answer Questions (VSA)

Answer Length: 20–30 Words

Syllabus: Strictly as per NCERT

Examination Relevance: CBSE Class 11 Annual & School Exams

Section A: Animal Tissues (Questions 1–20)

Epithelial Tissue

Q1. What is epithelial tissue?
Ans: Epithelial tissue consists of closely packed cells forming protective coverings and linings of organs, involved mainly in protection, absorption, secretion, and diffusion.

Q2. Name one characteristic feature of epithelial tissue.
Ans: Epithelial tissue cells are tightly packed with minimal intercellular space and rest on a basement membrane, providing structural integrity and protection.

Q3. Where is simple squamous epithelium found?
Ans: Simple squamous epithelium occurs in alveoli of lungs and blood capillaries, where it facilitates rapid diffusion and filtration.

Q4. Why is cuboidal epithelium suited for secretion?
Ans: Cuboidal epithelial cells possess a centrally placed nucleus and sufficient cytoplasm, enabling efficient secretion and absorption in kidney tubules and glands.

Q5. State one function of ciliated epithelium.
Ans: Ciliated epithelium helps in movement of substances such as mucus or ova across the epithelial surface through coordinated ciliary motion.

Connective Tissue

Q6. What is connective tissue?
Ans: Connective tissue supports, binds, and protects organs, consisting of cells embedded in an extracellular matrix made of fibres and ground substance.

Q7. Name the connective tissue that stores fat.
Ans: Adipose tissue stores fat, provides insulation, and acts as an energy reserve in the body.

Q8. Differentiate tendon and ligament in one sentence.
Ans: Tendons connect muscles to bones, while ligaments connect bones to bones and provide joint stability.

Q9. Why is cartilage flexible?
Ans: Cartilage contains chondrin matrix and elastic fibres, providing flexibility and support without being rigid like bone.

Q10. State one function of blood as a connective tissue.
Ans: Blood transports oxygen, nutrients, hormones, and metabolic wastes throughout the body.

Muscular Tissue

Q11. What is the function of muscular tissue?
Ans: Muscular tissue contracts and relaxes to produce movement, locomotion, and internal organ functions such as peristalsis.

Q12. Name the muscle tissue found in the heart.
Ans: Cardiac muscle tissue is found in the heart and enables rhythmic, involuntary contractions.

Q13. Why are skeletal muscles called voluntary muscles?
Ans: Skeletal muscles are under conscious control and allow voluntary movements like walking and lifting objects.

Q14. Where are smooth muscles located?
Ans: Smooth muscles are present in internal organs such as the stomach, intestine, blood vessels, and uterus.

Nervous Tissue

Q15. What is the basic unit of nervous tissue?
Ans: The neuron is the basic structural and functional unit of nervous tissue, responsible for receiving and transmitting nerve impulses.

Q16. State one function of nervous tissue.
Ans: Nervous tissue transmits electrical impulses to coordinate and control body activities.

Q17. Name two components of a neuron.
Ans: A neuron consists of a cell body, dendrites, and a long axon.

Q18. Where is nervous tissue found?
Ans: Nervous tissue is found in the brain, spinal cord, and peripheral nerves.

Q19. Why are axons long?
Ans: Axons are long to transmit nerve impulses over long distances efficiently within the body.

Q20. Name the supporting cells of nervous tissue.
Ans: Neuroglial cells support, protect, and nourish neurons.

Section B: Earthworm – Morphology and Anatomy (Questions 21–30)

Q21. Name the scientific name of earthworm.
Ans: The scientific name of earthworm is Pheretima posthuma.

Q22. What is metamerism?
Ans: Metamerism is the segmentation of the body into repeated units called metameres, enhancing flexibility and locomotion.

Q23. What is the function of setae in earthworm?
Ans: Setae help in locomotion by anchoring the body to the soil.

Q24. What is the role of clitellum?
Ans: Clitellum secretes mucus and forms a cocoon during reproduction.

Q25. How does respiration occur in earthworm?
Ans: Earthworms respire through moist skin by diffusion of gases.

Q26. Name the grinding organ in earthworm.
Ans: The gizzard grinds food mechanically during digestion.

Q27. What type of circulatory system is present in earthworm?
Ans: Earthworm has a closed circulatory system with blood flowing through vessels.

Q28. Name the excretory organs of earthworm.
Ans: Nephridia are the excretory organs that remove nitrogenous wastes.

Q29. What is the nature of earthworm nervous system?
Ans: It consists of a nerve ring and a ventral nerve cord with segmental ganglia.

Q30. Why is earthworm called a hermaphrodite?
Ans: Earthworm possesses both male and female reproductive organs in the same individual.

Section C: Cockroach – Morphology and Anatomy (Questions 31–40)

Q31. Name the scientific name of cockroach.
Ans: The scientific name of cockroach is Periplaneta americana.

Q32. How is the body of cockroach divided?
Ans: The body is divided into head, thorax, and abdomen.

Q33. What is the nature of cockroach exoskeleton?
Ans: The exoskeleton is made of chitin and provides protection and support.

Q34. Name the respiratory organs of cockroach.
Ans: Cockroach respires through tracheae opening outside via spiracles.

Q35. What type of circulatory system is found in cockroach?
Ans: Cockroach has an open circulatory system.

Q36. Name the excretory organs of cockroach.
Ans: Malpighian tubules are the excretory organs.

Q37. What is haemolymph?
Ans: Haemolymph is the circulatory fluid of cockroach that lacks respiratory pigments.

Q38. State one function of antennae in cockroach.
Ans: Antennae act as sensory organs for touch and smell.

Q39. What type of eyes does cockroach possess?
Ans: Cockroach possesses compound eyes for mosaic vision.

Q40. Name the digestive glands of cockroach.
Ans: Salivary glands and gastric caeca aid digestion.

Section D: Frog – Morphology and Anatomy (Questions 41–50)

Q41. Name the scientific name of frog.
Ans: The scientific name of frog is Rana tigrina.

Q42. Why is frog called an amphibian?
Ans: Frog lives both on land and in water during its life cycle.

Q43. How does frog respire on land?
Ans: Frog respires through lungs and moist skin on land.

Q44. What type of skin is present in frog?
Ans: Frog has moist, glandular, scaleless skin.

Q45. Name the chambers of frog heart.
Ans: Frog heart has two atria and one ventricle.

Q46. What type of circulatory system does frog possess?
Ans: Frog has a closed circulatory system.

Q47. Name the excretory organs of frog.
Ans: Kidneys are the primary excretory organs.

Q48. What is the function of webbed feet in frog?
Ans: Webbed feet help in swimming efficiently.

Q49. Where does digestion end in frog?
Ans: Digestion ends in the small intestine.

Q50. What is cloaca in frog?
Ans: Cloaca is a common chamber for digestive, excretory, and reproductive systems.