You are the biologist on an interstellar spacecraft and discover a life form. It

Question

You are the biologist on an interstellar spacecraft and discover a life form. It appears similar to life forms on Earth. You extract a number of molecules from the organism and characterize them. From the described properties, what kind of molecules are they likely to be and where are they likely to be found.

a. an amphipathic molecule that has two long hydrocarbon chains and a polar oligosaccharide head group.
b. another amphipathic molecule with two hydrocarbon chains and a phosphate-containing head group.
c. a polymer made of amino acids with hydrophobic amino acids on its outer surface in the middle of the molecule and hydrophilic amino acids on its outer surface on each end of the molecule.

Explanation / Answer

a.

Membrane lipids are amphipathic in nature and contain polar or nonpolar ends. Glycolipids are the class of lipids, which contain sugar (oligosaccharide) and two fatty acids. These are derived from sphingosine. These lipids contain polar oligosaccharide head group.

b.

Phospholipids are the class of lipids, which contain two fatty acid chains. The two fatty acid chains form hydrophobic tail, while hydrophilic head consists of phosphate. Thus, these lipids contain polar phosphate head group.

c.

Protein is a polymer that is made up of several amino acids. The hydrophobic amino acids are located in the middle of the molecule, while hydrophilic amino acids are located on outer surface on each end of molecule.

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.