The technique used to measure the rate of photosynthesis by counting oxygen bubbles is: MCQ with Answer and Explanation

Explanation:
Xenogamy is the type of cross-pollination where pollen grains are transferred from the anther of one plant to the stigma of a genetically different plant. This promotes genetic diversity. Autogamy is self-pollination within the same flower. Geitonogamy is the transfer of pollen between different flowers on the same plant (functionally cross-pollination but genetically self-pollination). Cleistogamy is closed, self-pollinating flowers.

Explanation:
Candidiasis (thrush) is an opportunistic fungal infection caused by Candida albicans, affecting moist areas like mouth, vagina, and skin folds. Ringworm is caused by dermatophytes, athlete's foot by Trichophyton, aspergillosis by Aspergillus.

Explanation:
Intrinsic factor, a glycoprotein secreted by gastric parietal cells, binds to vitamin B₁₂ and facilitates its absorption in the ileum. Absence or deficiency (pernicious anemia) leads to B₁₂ deficiency, causing megaloblastic anemia and neurological symptoms. HCl activates pepsin, pepsinogen is precursor, mucus protects.