Which vertebrate class is characterized by a three-chambered heart (except crocodiles)? MCQ with Answer and Explanation

Explanation:
Lymph is interstitial fluid that has entered lymphatic capillaries. When lymph vessels are blocked (e.g., filariasis), lymph accumulates, causing swelling (lymphedema). Plasma is blood fluid, synovial in joints, serum is plasma without clotting factors.

Explanation:
Individuals with blood group 'O' have red blood cells that lack both A and B antigens on their surface. Because there are no antigens to react with the recipient's antibodies, their blood can be safely transfused to individuals of any ABO blood group in emergencies. However, their plasma contains both anti-A and anti-B antibodies.

Explanation:
Myoglobin is an oxygen-binding protein in muscle. Hemoglobin contains iron and is red; hemocyanin contains copper and is blue. Hemoglobin is in RBCs.