Question 19M.2.HL.TZ1.a
| Date | May 2019 | Marks available | [Maximum mark: 4] | Reference code | 19M.2.HL.TZ1.a |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | Compare and contrast | Question number | a | Adapted from | N/A |
Compare and contrast the structure of a typical prokaryotic cell with that of a mitochondrion.
[4]
differences
a. prokaryote has cell wall but mitochondrion does not ✔
b. mitochondrion has double membrane whereas prokaryote has single membrane
OR
«Gram negative» bacteria have cell wall between two membranes whereas mitochondria has intermembrane space between two membranes ✔
c. mitochondrion has cristae/invaginations of inner membrane but prokaryote does not
OR
prokaryote «may have» flagella/pili/«slime» capsule which mitochondria do not have ✔
similarities
d. 70S ribosomes in both ✔
e. DNA in both / loop of DNA in both / naked DNA in both ✔
f. shape similar/both rod shaped/OWTTE
OR
size of both is similar/both about 3 μm long ✔
g. both are membrane-bound/OWTTE ✔
Answers were spread over the whole of the four-mark range. The scale bars allowed the sizes of both to be calculated – they were close, but even so a substantial number of candidates claimed that one or other was significantly larger.
