Question

-how are sterols considered both primary and secondary metabolites

-the photosynthetic carbon reduction cycle is autocatalytic, what does this mean and whats its advantage

-describe the relationship between absorption spectrum and action spectrum. how is the action spectrum significant to a plant physiologist?

Answer 1

1. sterols are the compounds which contain four rings(steroids) arranged along with the alcohol(OH) group.Sterols are considered primary metabolism is it is directly involved in the development that is it is located in the cell membrane and involves in cell signalling directly( Example:zoosterol that is cholestrol) ,as well as it is called secondary metabolites because it is directly do not involves but indirectly functions in the cell when they receive signals from outside ( ex:phytosterols present in grains involved in decrease of cholestrol levels).

2. Photosynthetic carbon reduction cycle is also known as Calvin cycle.It is autocatalytic means the same product compound is acts as the catalyst for the production of same product. In calvin cycle the PGA and only one molecule is used for convertion into sugar,but one molecule is not sufficient by using the other sugars like seven carbon(sedulose7 phophate) which can convert more moleculePGA into glucose.

3.Absorption spectra is to measure the wavelength of light by all thepigments absorbed by the  leaf where as action spectrum is rate of the graphical representation of only the pigments absorb light which participitate in photosynthesis.Action spectrum is a part of the absorbed spectrum and  it is majorly significant for plants to determine which light and wavelength is important for the photosynthesis process and what are the pigments and types of them useful for the process and which light is absorbed by which pigment.and majorly know the rate of photosynthesis and differences to know the dark and light reactions, and light respiration.