IMAT 2011 Q44 [Prokaryotic and Eukaryotic cells]

Which of the features below may be present in both prokaryotic cells and eukaryotic animal cells?

  1. glycogen
  2. a cell wall
  3. DNA in loops
  4. cytoplasm containing ribosomes

A. 1 only

B. 1 and 2 only

C. 1, 2 and 3 only

D. 1 and 4 only

E. none

As always, let׳s analyze the question before going into the answer. We are being asked about the features both prokaryotic cells, and eukaryotic ANIMAL cells have IN COMMON, meaning, they both posses!

Glycogen – this one is a hard one, you might think glycogen only exists in muscle cells in animals, but! Fungi and bacteria also have glycogen as a “glucose storage fuel system”! If you did know, congratulations, you study the cells section well for the IMAT, but if you didn’t, don’t worry, Cambridge KNOWS this one is a hard one, so let’s just keep going

A cell wall – Basic knowledge, of knowing animal calls does not contain a cell wall, only plant cell (and some single-celled eukaryotic!), a good thing for us that we KNOW already to read the question CAREFULLY, finding that we are comparing prokaryotic to ANIMAL cells. (good thing that I am here ey?)

DNA in loops – or with their original name “PLASMIDS”, are DNA circles that can be found ONLY in prokaryotic cells, and some fungi (you can find it in different places but for the IMAT is unnecessary), because we were asked about an ANIMAL cell, we know this answer can׳t to be right but if you look at the Mitochondria, which also have DNA in loops, you can see that in general, we do have DNA in loops!

Cytoplasm containing ribosomes – in prokaryotic cell, we don’t have membrane-bound cell organelles, therefore we don’t have RER (rough endoplasmic reticulum), we DO have ribosomes floating in the cytoplasm!, in animal cell WE DO have RER, But there are 2 PLACES YOU CAN FOUND RIBOSOMES, on the RER, and also floating in the cytoplasm! So this one is true.

As far as we know, 1 and 4 are correct, therefore D is the correct question, but what if we forgot or didn’t know that glycogen can be found in prokaryotic? As you can see, 4 can only be found in “D”, and D also contains 1, so we must assume (if we know the basic idea that ribosomes can be found in the cytoplasm of eukaryotic cells) that 1 is also correct.

D is the answer