Question

1. Describe the structure of a phospholipid.

2. What is the function of phospholipids?

3. What is cholesterol and what role does it play in the body?

4. What part of the nucleotide forms the backbone of a nucleic acid?

5. What does DNA stand for? RNA?

Answer 1

Q1. Phospholipids contains  A diglyceride, a phosphate group and a simple organic molecule (choline) or he consists of two hydrophobic fatty acid tails and hydrophilic phosphate head groups which are joined together by a glycerol molecule.

Q2. The phospholipid membrane allows free diffusion of some small molecules such as oxygen, carbon dioxide, and small hydrocarbons, but not charged ions, polar molecules or other larger molecules such as glucose. they form the most abundent lipds found in the plalma membrane and other iological membranes which confers structural integrity and also has a role in cellular communications

Q3. Cholesterol is a sterol found in animal cells membranes.Depending on the temperature, cholesterol has distinct effects on membrane fluidity. Reduces membrane fluidity by reducing phospholipid movement.At high temperatures, cholesterol interferes with the movement of the phospholipid fatty acid chains, making the outer part of the membrane less fluid and reducing its permeability to small molecules. At low temperatures, however, cholesterol has the opposite effect: By interfering with interactions between fatty acid chains, cholesterol prevents membranes from freezing and maintains membrane fluidity.

Q4. Sugar phosphate backbone

Q5. These two are the nucleic acids present in living systems. DNA is an acronym for deoxyribonucleic acid and RNA stands for Ribonucleic acid.