1, O because if either shows present it's O.
Oxygen is an abiotic factor that is beneficial by-product of primary production.
<u>Explanation:</u>
The non living parts of an ecosystem that mainly affects the living organisms in it are called as an abiotic factor. These can include soil, temperature, water, oxygen and sunlight. The major energy source in earth is Oxygen which is abiotic factor.
It is very essential for the photosynthesis process to take place. Here, the plants converts water and carbon dioxide into oxygen and sugar. This becomes food for plants. Then these plants are eaten by animals. Thus oxygen is an important and beneficial by-product of photosynthesis. Oxygen is also very important for the survival of human beings.
The right answer is: vitamin C and choline
Choline (vitamin B4) is the precursor on the one hand acetylcholine (important neurotransmitter and neuromodulator) and on the other hand, the cascade initiated by betaine (intermediate in the biological methylation and precursor of membrane lipids). In this, it is considered, by extension, as an integral part of the family of B vitamins,
Vitamin C protects against cellular aging, is essential for the immune defenses and increases the assimilation of iron of plant origin. It also contributes to the formation of collagen. Its deficiency leads to a disease called scurvy (hence the ascorbic acid name of vitamin C).
Uranus is the 7th planet from the sun :))
Carbon atoms are converted into metabolites like acetic acid, lactic acid, aldehydes, etc via the action of different bacteria. In the process of fermentation or cellular respiration, carbon atoms are cleaved into three carbon molecule called pyruvate then eventually forming into metabolites.
