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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

You have 2 plants of the same type and same size, same amount of leaves. one of them is put inside the house and the other one is put in the balcony. you water them saturday, one plant with 200 ml and the other with 400 ml of water. which one of your plants need less water? explain.

Match the following terms describing electrical events with the correct phases of the cardiac cycle. the ventricular muscle cells depolarize at the start of this phase. during this phase, na+ entry through the funny channels causes the pacemaker potential of sa nodal cells to gradually become less negative until it reaches threshold. the ventricular muscle cells repolarize right before this phase. the cytosolic concentration of calcium in the contractile cells of the ventricle is highest during this phase. a. isovolumetric relaxation b. ventricular ejection c. isovolumetric contraction d. ventricular filling