Sponges represent one of the simplest animal body plans. Their bodies lack true tissues. Class 9

Sponges represent one of the simplest animal body plans. Their bodies lack true tissues. Class 9

Question 1.

Sponges represent one of the simplest animal body plans. Their bodies lack true tissues and organs. Which feature of sponge cells supports its classification under the animal kingdom? Class 9

(i) Absence of mitochondria

(ii) Ability to photosynthesise

(iii) Presence of a cell membrane

(iv) Presence of a cell wall

Answer:

(iii) Presence of a cell membrane:

Sponges are classified under the animal kingdom (Animalia). Animal cells have a cell membrane but do NOT have a cell wall. Plants and fungi have cell walls. The presence of a cell membrane (without a cell wall) is consistent with animal cell structure. Sponges are also multicellular and heterotrophic (they depend on other organisms for food), which are characteristic features of animals.