The scientist who developed the first effective polio vaccine was: MCQ with Answer and Explanation

Explanation:
The Foramen of Panizza is a small opening located between the left and right aortic arches at the base of the heart in crocodilians (crocodiles, alligators). It allows blood to flow between the two systemic arches. During diving, when pulmonary resistance increases, this foramen allows deoxygenated blood to bypass the lungs and enter the systemic circulation, conserving oxygen for vital organs. Frogs have a three-chambered heart without this specific foramen.

Explanation:
Pleiotropy is when one gene influences several distinct phenotypic characteristics. Example: sickle cell disease (mutant hemoglobin affects RBC shape, causing anemia, pain, organ damage). Polygenic traits involve many genes, codominance both alleles expressed, epistasis gene interaction.

Explanation:
Seminal vesicles produce a fructose-rich fluid (energy for sperm), and the prostate gland adds a milky, alkaline fluid to form semen. The testis produces sperm, epididymis stores them, vas deferens transports.