Describe the interactions between transcription factors and promoter sites that lead to the initiation of transcription. Predict the effect of adding negative regulation molecules to the interaction.

Ablastocyst is a group of cells that forms after a human egg is fertilized. the blastocyst consists of two types of cells. some of these cells will become the placenta. what do the other cells develop into?

Archaebacteria use for movement. celia flagella pili cell walls

49 ! how are energy cycles and growth cycles related?