These include the chemical. cellular. tissue organ. organ system and the organism level
<u>Answer</u>: C) Hydrophobic interior, hydrophilic exterior
<u>Explanation</u>:
- The <em>plasma membrane</em> of the cell defines its boundary and separates its internal components from the external environment.
- The basic components of the plasma membrane include phospholipids, carbohydrates, proteins, and cholesterol.
- The plasma membrane is a phospholipid bilayer, with <em>hydrophobic</em> tails of the phospholipid projecting <em>inwards</em> and the <em>hydrophilic</em> exterior in contact with the external environment.
- <em>Due to this, the plasma membrane has a hydrophobic interior and hydrophilic exterior. </em>
<span>The 4 categories of macromolecules include carbohydrates, proteins, lipids, and nucleic acids. Carbohydrates (grains and vegetables) are the largest group at the base of the pyramid, proteins (milk, poultry, eggs, nuts) follow up the pyramid while lipids (fats and oils) are the least amount at the summit of the pyramid. </span>
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</span><span>The aim of the pyramid is to recommend ideal rations for a healthy diet. Carbohydrates provide most of the energy needs for the days’ activities hence taking the largest portion. Proteins are used in building muscles, f0r nutrition, and body’s immunity hence required in lesser amounts compared to carbohydrates. Lipids help the body store energy since they have thrice as much energy as carbohydrates.They also a constituent of cell membranes and also help deliver vitamins. They are required in the least amount to avoid obesity and related illnesses such as cardiovascular <span>diseases</span></span>
<span>The answer is A. This is because the P53 gene is involved in a cell cycle regulation and is thought to hold the cell in a particular phase until DNA defects are repaired. </span>