What are the functions of these macromolecules in a cell: lipids and proteins?

Question

can you pleease provide me with an example for each? Thanks!!

Answer 1

Lipids:
1. Store energy
2. Act as insulation
3. Make protective coatings (waxes, etc.)
4. Make up important parts of plasma membranes as well as other membranes that cover and make up organelles. (the phospholipids)

Proteins:
1. Act as enzymes
2. Structural (cytoskeleton, microtubules in cilia and flagella)
3. Give immunity
4. Build structures such as hair, nails, hooves, ...
5. Carry oxygen (hemoglobin)

Answer 2

Carbohydrates: glycogen a form of stored energy in the liver and muscles. Glucose, fructose (and other monosaccharides) though carbohydrates are not macromolecules, used as energy source and to form glycoproteins employed in mucous, antigen molecules on cell membranes, in connective tissue. Lipids, as triglycerides, for energy production, cell membranes, neuron insulation (myelin sheath), lipoproteins. Proteins numerous uses, enzymes, many hormones, transport molecules, signal molecules, membrane channels, muscle, support tissue. Nucleic acids, DNA for heredity, RNA for gene transcription and protein synthesis.

Answer 3

Lipids = storage of energy. May also act as hormones or transcription factors.

EX: Fats are stored as triglycerides in cells. Adrenaline is a steroid hormone (derived from lipids) that speeds up cellular metabolism. It also enhances receptors on certain flight-or-flight response cells.

Proteins: Proteins are peptides that participate in cell-cell recongition, immune responses, and many act as enzymes that catalyze various reactions in a cell. IgA is an example of a protein involved in immune responses. Enolase is a protein that catalyzes the last step in glycolysis.