Practice MCQs, Assertion–Reason, Match List and Fill in the Blanks from NCERT Class XI Animal Kingdom — answers & concise explanations.
Animal Kingdom - Class-XI: Practice ( MCQs, Assertion-Reason, Match List-I with List-II and Fill in the Blanks) for CBSE and NEET preparation 2026.
Select Question Type:
This Page Score: 0/0
Q201.
Assertion (A): Sponges exhibit a cellular level of organisation.
Reason (R): In sponges, the cells are arranged as loose cell aggregates.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: A [ ]
Remark: Both A and R are true and R is the correct explanation of A. Explanation: The cellular level of organisation is defined by cells being arranged as loose aggregates, which is the pattern seen in sponges.
Q202.
Assertion (A): Coelenterates show a tissue level of organisation.
Reason (R): In coelenterates, tissues are grouped together to form organs.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: C [ ]
Remark: A is true but R is false. Explanation: Coelenterates indeed have tissue level of organisation. However, grouping of tissues to form organs is characteristic of organ level of organisation, not tissue level.
Q203.
Assertion (A): The digestive system in Platyhelminthes is called incomplete.
Reason (R): It has only a single opening to the outside that serves as both mouth and anus.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: A [ ]
Remark: Both A and R are true and R is the correct explanation of A. Explanation: An incomplete digestive system has a single opening for both ingestion and egestion, as in Platyhelminthes.
Q204.
Assertion (A): Arthropods have an open type of circulatory system.
Reason (R): In an open circulatory system, blood is circulated through a series of vessels of varying diameters.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: C [ ]
Remark: A is true but R is false. Explanation: Arthropods do have an open circulatory system. The reason given actually defines a closed circulatory system (blood confined to vessels). In open systems blood bathes tissues directly.
Q205.
Assertion (A): Most sponges are asymmetrical.
Reason (R): In sponges, any plane passing through the central axis of the body divides the organism into two identical halves.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: C [ ]
Remark: A is true but R is false. Explanation: Most sponges are indeed asymmetrical. The reason describes radial symmetry (where planes through an axis give equal halves), which is not applicable to asymmetry.
Reason (R): The body of an adult echinoderm can be divided into identical left and right halves in only one plane.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: C [ ]
Remark: A is true but R is false. Explanation: Adult echinoderms have radial symmetry (multiple planes through central axis produce similar halves); the reason describes bilateral symmetry (single plane produces identical left and right halves).
Q207.
Assertion (A): Coelenterates are diploblastic animals.
Reason (R): Their cells are arranged in two embryonic layers: an external ectoderm and an internal endoderm.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: A [ ]
Remark: Both A and R are true and R is the correct explanation of A. Explanation: Diploblastic animals have two germ layers—ectoderm and endoderm—as seen in coelenterates.
Q208.
Assertion (A): Platyhelminthes are triploblastic animals.
Reason (R): The developing embryo in Platyhelminthes has a third germinal layer, mesoderm, between the ectoderm and endoderm.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: A [ ]
Remark: Both A and R are true and R is the correct explanation of A. Explanation: Triploblastic animals possess mesoderm as the third germ layer; Platyhelminthes are triploblastic.
Q209.
Assertion (A): Annelids are considered true coelomates.
Reason (R): In annelids, the body cavity is lined by mesoderm.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: A [ ]
Remark: Both A and R are true and R is the correct explanation of A. Explanation: Coelomates have a body cavity (coelom) lined by mesoderm; annelids are true coelomates.
Q210.
Assertion (A): Aschelminthes are pseudocoelomates.
Reason (R): In aschelminthes, the body cavity is absent.
[Animal-Kingdom] [class-xi]
a) Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
b) Both Assertion (A) and Reason (R) are true but Reason (R) is not the correct explanation of Assertion (A).
c) Assertion (A) is true but Reason (R) is false.
d) Assertion (A) is false but Reason (R) is true.
Correct Option: C [ ]
Remark: A is true but R is false. Explanation: Aschelminthes are pseudocoelomates (they have a body cavity—the pseudocoel), but the reason incorrectly states that the body cavity is absent; absence of body cavity is acoelomate condition.
