According to the big bang theory, how did the universe begin? what had to happen before atoms could form?

Which organisms have pharyngeal arches that develop from all three germ layers and go through the same development stages as embryos? 1.bird 2.ladybug 3.starfish 4.snake

Glucose is a form of sugar found in the blood cells use glucose as a source of energy, but too much or too little can cause serious health issues so, the body uses the hormone insulin to regulate glucose n the blood insulin maintain glucose levels in the blood if blood glucose lovels got very high, what would you expect to see happen to insulin levels?

How does natural selection change thephenotypes within a population over time?