DP Biology (last assessment 2024)

Test builder »

Question 19M.3.HL.TZ2.1b.ii

Select a Test
Date May 2019 Marks available [Maximum mark: 2] Reference code 19M.3.HL.TZ2.1b.ii
Level HL Paper 3 Time zone TZ2
Command term Outline Question number b.ii Adapted from N/A
b.ii.
[Maximum mark: 2]
19M.3.HL.TZ2.1b.ii

The drawing shows part of a Thunbergia grandiflora plant. It has been widely cultivated as an ornamental garden plant.

[Source: from Wight, R., Icones Plantarum Indiae Orientalis, vol. 3 (1846)]

The drawing shows a section through a T. grandiflora flower, which contains a honeybee (Apis mellifera).

[Source: © D G Mackean (www.biology-resources.com/drawing-plant-flower-tropical-06.html)]

(b.ii)

Outline the relationship the bee has with the T. grandiflora flower.

[2]

Markscheme

a. mutualistic relationship
OR
bee gets nectar/pollen «as food» AND flower is pollinated/fertilized ✔ Both needed.

b. when bee enters, pollen from anther sticks to it ✔

c. pollen is picked up by stigma «of same or other flower» ✔

Examiners report

Although some could not write "mutualistic/mutualist", the majority could outline the relationship, but some confused pollination, fertilization and seed dispersal; it was more difficult for most to name either the anther or the stigma.