The structure in the female reproductive system where the fetus develops is the: MCQ with Answer and Explanation

Explanation:
Jean-Baptiste Lamarck proposed the theory of inheritance of acquired characters, based on the use and disuse of organs. Charles Darwin proposed the theory of evolution by natural selection, emphasizing survival of the fittest. Hugo de Vries, a Dutch botanist, proposed the mutation theory of evolution after working on evening primrose, stating that evolution occurs via sudden, large mutations (saltations). All statements are correct.

Explanation:
Chief cells (peptic cells) in the gastric mucosa secrete pepsinogen, which is converted to active pepsin by HCl. Pepsin digests proteins into peptides. Parietal cells secrete HCl and intrinsic factor. Mucous cells produce mucus that protects the stomach lining. G cells secrete gastrin hormone. Pepsin functions optimally at pH 1.8-2.0. The stomach thus initiates protein digestion.

Explanation:
Earthworms (annelids) have a closed circulatory system with blood contained within vessels. Cockroach, snail, and butterfly have open circulatory systems where hemolymph bathes organs directly.