All of the liquid molecules in cell membranes amphipathic (or amphiphilic) -that is, they have a hydrophilic ("water loving") or polar end and a hydrophobic ("water fearing") or nonpolar end. The most abundant membrane lipids are the phospholipids. These have a polar head group and two hydrophobic hydrocarbon tails.
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Human Immunodeficiency Virus -- this is HIV, the virus that causes AIDS.
Flu viruses. There are lots of different strains of flu virus, which is why new vaccines have to be made every year.
Cold virus. The common cold is caused by a virus.
It is not C. I got it wrong. It is A water!
Besides producing sugar for itself a plant also needs to absorb nitrogen to build proteins, salts to make concentration gradients and potassium to make enzymes.
<u>Explanation:</u>
Plant sugar is glucose and plants produce it by the process of photosynthesis making use of energy from sunlight, carbon dioxide absorbed from the atmosphere and the presence of chlorophyll in its parts. Plants also require components other than this. Nitrogen is essential to make proteins and it cannot be directly absorbed from the atmosphere but has to be absorbed from the soil.
Potassium is an essential component which is absorbed from the soil. It facilitates the activation of enzymes which play a crucial role in plant metabolism. When plants lack potassium they won’t have enough energy for proper growth and will have poorly formed roots and weak stems.