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Which of the following is true w.r.t. cn...

Which of the following is true w.r.t. cnidoblast?
a. These oval shaped cells are abundant on tentacles than body surface
b. cnidocyte is a part of cnidoblast which is filled with a poisonous fluid
c. once nematoblast is used, it migrates to gastrovascular cavity and digested
d. Nucleus is present in the centre of cell

A

(A) only

B

(A) and (B)

C

(A) and (C)

D

(B) (C) and (D)

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question regarding cnidoblasts, let's analyze each option step by step: ### Step 1: Analyze Option A - **Statement**: "These oval-shaped cells are abundant on tentacles than body surface." - **Analysis**: Cnidoblasts, also known as cnidocytes, are indeed more abundant on the tentacles of cnidarians than on their body surface. This is because they play a crucial role in capturing prey and defense mechanisms. - **Conclusion**: This statement is **true**. ### Step 2: Analyze Option B - **Statement**: "Cnidocyte is a part of cnidoblast which is filled with a poisonous fluid." - **Analysis**: Cnidocytes (or nematocytes) are specialized cells within cnidoblasts that contain nematocysts, which are organelles filled with toxic fluid used for defense and capturing prey. - **Conclusion**: This statement is **true**. ### Step 3: Analyze Option C - **Statement**: "Once nematoblast is used, it migrates to gastrovascular cavity and digested." - **Analysis**: This statement is incorrect. When a nematocyst (the stinging part of the cnidocyte) is discharged, it does not migrate to the gastrovascular cavity to be digested. Instead, it remains in place and can be reused. - **Conclusion**: This statement is **false**. ### Step 4: Analyze Option D - **Statement**: "Nucleus is present in the centre of cell." - **Analysis**: In cnidocytes, the nucleus is located at the basal side of the cell, not in the center. This is a key characteristic of these cells. - **Conclusion**: This statement is **false**. ### Final Conclusion Based on the analysis: - **True Statements**: A and B - **False Statements**: C and D Thus, the correct answer is that options A and B are true regarding cnidoblasts.
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