What is the meaning of vigil

What links the two strands in a dna helix together in the middle? a. phosphate groups b. sugar rings bonded together c. proteins d. bases with hydrogen bonds

Which symbols below represent the ions found in the glass of water ? a. oh- and h+ b. co2 and o2 c. o2 and h2 d. nh3- and h+

Drag each tile to the correct box. arrange the phases of mitosis in the correct order. 1 (condensation of chromosomes) 2 (separation of chromosomes) 3 (formation of spindle fibers) 4 (alignment of chromosomes in the center of the cell) 5 (pinching of the cell membrane)