The right answer is vitamin C—citric acid.
Vitamin C or ascorbic acid protects against cellular aging, is essential for the immune defenses and increases the assimilation of iron of plant origin.
Citrate is a biological molecule found in all living organisms because it is involved in the Krebs cycle (or citrate cycle) to produce energy.
Answer:
CFU/mL
Explanation:
Given -
a) Number of colonies of bacteria is equal to 
b) Total volume of the solution is equal to 
mL
c) Dilution factor is equal to 
As we know that
CFU/mL 
Where N is the number of bacterial colonies, DF is the dilution factor and V is the volume
Substituting the given values in above equation, we get -
CFU/mL 
The three examples of stimulus include;
1. Hit the skin with a needle or pin is a good example of stimulus. The sudden removing of the hand is the response.
2. When somebody bangs a door you jump if you were unaware because of the sound. The jumping is the response to a stimulus.
3. Holding a hot plate we fling hand away from it. The stimulus here is holding the plate while removal of the hand is the response.
Stimulus is the change or cause in an organism's surrounding which causes the organisms to react.
<span>Transcription is the first step of gene expression, in which a particular segment of DNA is copied into RNA (especially mRNA) by the enzyme RNA polymerase. Both DNA and RNA are nucleic acids, which use base pairs of nucleotides as a complementary language.
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What I know is that amino acid has side chain, amine groupe ,and groupe of carboxyl so what make them difference is side group where the is 20 different R-group which give each individual characteristics
