Answer:
The correct ansqwer is- Vitamin D
Explanation:
Vitamin D is the vitamin that can be synthesized by the human body itself therefore it is not an essential vitamin for human beings. Human skin is the part that helps in making this vitamin in humans.
The natural form of vitamin D is vitamin D3 which is formed by the sunlight exposure on the skin. When we expose our skin in the sunlight the UV radiation penetrated our skin and converts provitamin D3 into pre-vitamin D3 then this previtamin can be isomerized into the natural form of vitamin D Which is vitamin D3. So the right answer is vitamin D.
Answer:
The preferable option will be - A.
A. similar environments and specific traits increased their chances of survival.
Explanation:
- The shark and dolphins have similar body shape and fins. But shark is a fish and dolphin is a mammal.
- Both of them are exposed to similar kind of environments. Both of them possess a specific kind of alternative characters and traits.
- So, Some species may have similar body structures even if they are not related because they evolved in similar environments and specific traits increased their chances of survival.
The two categories would be Biotic and Abiotic
Photorespiration limits casualty products of light reactions
that build up in the absence of the Calvin cycle. In many plants,
photorespiration is a problem because on a hot, dry day it can drain as much as
50% of the carbon fixed by the Calvin cycle. The closing of stomata reduces access to CO2
and causes O2 to build up. These conditions favor a seemingly not useful process
called photorespiration. In most plants
(C3 plants), initial fixation of CO2, via rubisco, forms a three-carbon
compound. In photorespiration, rubisco
adds O2 instead of CO2 in the Calvin cycle. Photorespiration eats up O2 and
organic fuel and releases CO2 without producing ATP or sugar. Photorespiration
can evolve relic because rubisco first evolved at a time when the atmosphere
had far less O2 and more CO2.
The answer is c) a number and a unit
