Select the correct answers 1. Biuret reaction is positive for all amino acids
2. The serine amino acid contains the -SH group
3. Glutathiol contains glutamic acid, glycine, histidine
4. Tripeptides and proteins always give a positive Biuret reaction

yes its like the dead sea which is full of salt which makes you stay afloat

so yes an egg will float in salt

x would be the most and the least would be y because there are more fruit   and seeds than flock z has insects

i believe it's c. the trait for large beaks will be passed on to future generations through natural selection.

since eventually smaller beaks would have to find another source of food or even eventually just die out from the lack of food.