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.

Answer 1

The molecules extracted from the newly discovered life form resemble phospholipids and proteins from Earth, with phospholipids likely forming cell membranes and proteins potentially serving various cellular functions.

Step-by-step explanation:

Based on the descriptions given, the molecules you have characterized from the discovered life form are likely to be phospholipids and proteins. Phospholipids are amphipathic molecules composed of a glycerol backbone with two fatty acid tails and a phosphate-containing head group.

This molecular structure enables phospholipids to form cell membranes, with the hydrophobic tails facing inward, away from water, and the hydrophilic heads facing outward, towards the water.

Proteins are polymers of amino acids and can have varied structures, including hydrophobic or hydrophilic regions, allowing them to perform a plethora of functions throughout the cell.

Option (A) describes a molecule that could be part of membrane structures that resemble glycolipids, which are similar to phospholipids but have oligosaccharide groups instead of phosphate groups. Option (B) is essentially the description of a typical phospholipid, which is a major component of cellular membranes.

Lastly, option (C) might describe a protein that could be involved in interactions with other molecules, possibly functioning as an enzyme, receptor, or structural component depending on the protein's specific location and shape within the organism.