The base pairs in a dna strand are held together with hydrogen bonds. if the two nitrogenous bases in each pair were held together with covalent bonds instead of hydrogen bonds, what effect would it have on the cell? a. the cell could open and close the dna strand with less effort if the bonds were covalent. b. each time the dna strand opened the cell would need to replace the nitrogenous bases. c. the cell would have to take in and use more energy in order to break the covalent bonds. d. since the covalent bonds are unbreakable it would be difficult for the cell to make mrna.

the option C is correct because covalent bond is stronger than hydrogen bond ...The cell would have to take in and use more energy in order to break the covalent bonds.

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.

it has to be understood that the sea water contains a huge amount of sodium and chlorine ions and if they enter the cell of the atlantic cod fish, the cell will shrivel and the fish will die. to avoid such a condition, the fish uses active transport for the purpose of removing the ions against the gradient.

explanation:

the atlantic cod is not a maritime osmoconformer. its native application of salts is less than that of the seawater it lives in. it is continually falling water from the gills to the ocean via osmosis.

countering that, the fish is going to be swallowing seawater. but since its internal collection of salts is lower than seawater, the fish will want to go free of excess salt, and since that's going upon a gradient, then active transport, requiring energy, must be used to pump out the salt. much marine fish use the organs to filter out the salt and these fish discharge very straight urine.