ibo.org
Updates to Questionbank

User interface language: English | Español

« Back to questions in DP Biology

Date May 2019 Marks available 1 Reference code 19M.1.SL.TZ1.2
Level Standard level Paper Paper 1 Time zone Time zone 1
Command term Compare Question number 2 Adapted from N/A

Question

The image shows an electron micrograph of part of a cell.

[Source: Dr. Eldon Newcomb – Emeritis Professor at The University of Wisconsin – Madison.]

 

Which features do the two structures labelled X and Y have in common?

A. They are surrounded by a double membrane.

B. They contain 70S ribosomes.

C. They contain naked DNA.

D. They are only found in leaf cells.

Markscheme

A

Examiners report

There was criticism that the resolution of the micrograph wasn’t high enough, but it was typical for electron micrographs of plant cells and the internal structure of chloroplasts and the nucleus was clear. This skill from 1.2 of the Core was being tested: Interpretation of electron micrographs to identify organelles and deduce the function of specialized cells. The nucleus and chloroplasts both had a typical appearance, so well-prepared candidates should have been able to identify them. Answer A could then be chosen either by eliminating the incorrect answers, or by knowing that both nucleus and chloroplast are double membraned. The endosymbiotic theory for the origin of chloroplasts should have helped inform candidates about the two membranes of chloroplasts.

Syllabus sections

Core » Topic 1: Cell biology » 1.2 Ultrastructure of cells
Show 53 related questions
Hide related questions
Core » Topic 1: Cell biology
Core

View options

© International Baccalaureate Organization 2023
International Baccalaureate® - Baccalauréat International® - Bachillerato Internacional®
Terms and conditions | Privacy policy