Question

Which of the following statements are correct?
1. Frogs lack nictitating membrane.
2. Frogs have 3 chambered heart.
3. Frogs possess 2 portal systems: renal portal system & hepatic portal system.

• A. Only 1 is correct
• B. Both 1 & 2 are correct
• C. Only 2 is correct
• D. Both 2 & 3 are correct

Answer 1

The correct option is D Both 2 & 3 are correct

Frogs possess simple eyes which are protected by an immovable upper eyelid, movable lower eyelid and a transparent membrane which is called nictitating membrane. Nictitating membrane provides protection and moisture to the eye without affecting visibilty.
Frogs have closed circulatory system with a three chambered heart which is made of two upper auricles and single lower ventricle.
Portal system is a part of circulatory system. Frogs possess two well developed portal systems passing through liver and kidneys namely, hepatic portal system & renal portal system respectively.