The gland that produces tears is the: MCQ with Answer and Explanation

Explanation:
Rana tigrina is the scientific name of the Indian bullfrog. Homo sapiens refers to humans, Felis domestica is the domestic cat, and Crocodylus palustris is the marsh crocodile. Binomial nomenclature gives each organism a unique genus and species name. Rana is the genus, tigrina the species, both italicized when printed.

Explanation:
Charles Darwin, in 'On the Origin of Species' (1859), proposed natural selection as the mechanism for evolution, based on variation, inheritance, and differential survival. Mendel discovered genetics, Pasteur disproved spontaneous generation, Lamarck proposed inheritance of acquired characters. Wallace independently arrived at natural selection.

Explanation:
Mendel's first law (law of segregation) states that two alleles of a gene separate during gamete formation (meiosis) so that each gamete receives only one allele. This is due to the separation of homologous chromosomes in anaphase I of meiosis. Fertilization restores the diploid number. This law explains the 3:1 phenotypic ratio in monohybrid crosses. Mitosis maintains the allele pair.