How many enzymes does a cell contain ? and do they perform the same function ?

Apart of the periodic table is shown. a portion of the sixteenth and seventeenth columns of the periodic table is shown. column 16 reads eight oxygen, 16 sulfur, and 34 selenium. column 17 reads nine flourine, 17 chlorine, and 35 bromine. which of the following elements is less reactive than the others? bromine (br) oxygen (o) selenium (se) sulfur (s)

The negative change found inside the plasma membrane is created by potassium ions sodium ions hydrogen ions chlorine ions

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen