Consider statements about human immunity: 1. Innate immunity is present from birth. 2. Vaccination provides artificial active immunity. 3. Antibodies are produced by T-lymphocytes. Which are correct? MCQ with Answer and Explanation

Explanation:
Charles Darwin, an English naturalist, proposed the theory of evolution by natural selection in his seminal book 'On the Origin of Species' (1859). His theory, based on observations from his voyage on the HMS Beagle (especially the Galapagos finches), states that species evolve over time through the process of natural selection, where individuals with advantageous traits are more likely to survive and reproduce.

Explanation:
Bile is produced by the liver and stored in the gall bladder. The gall bladder does not produce bile. All other statements are correct.

Explanation:
The bicuspid valve (mitral valve) has two cusps and is located between the left atrium and left ventricle, preventing backflow during ventricular systole. The tricuspid valve is on the right side. Semilunar valves are at the exits of the aorta and pulmonary artery. Mitral valve prolapse is a common condition.