As a rule of thumb, in order to improve the reliability and accuracy of an experiment, it is best if the experiment is repeated several times. The increased number of trials ensures that the readings observed have minimal random error.
This is all about dominant and recessive genes. According to the picture it looks like the yellow flowers have the dominant genes YY and the green flowers the recessive yy. You breeded the YY with the yy to get Yy. Now you have a plant with the dominant and recessive gene. The green flowers are recessive so if you breed 'y' with anything you get yellow flowers whether they only have the'Y' gene or the both 'Y' and 'y'.
DNA is being used as a template to make a molecule of mRNA.
Well, there are two kinds of organisms: osmoregulators, that can regulate the level of salt and the salinity does not affect them (an example is salmon: for salmon this sentence is true. Generally, for most fish this sentence is true)
However, for some species, such shark - osmoconformers - this is false: they are affected by the salinity. in general I would conclude that This is false: the marine salinity DOES affect the fish (and other organisms) living there.
