User interface language: English | Español

Date May 2017 Marks available 2 Reference code 17M.2.HL.TZ2.3
Level Higher level Paper Paper 2 Time zone Time zone 2
Command term Outline Question number 3 Adapted from N/A

Question

This image shows a normal red blood cell.

These images show two red blood cells that have been placed in solutions with different concentrations of solutes.

Outline the properties of water molecules that permit them to move upwards in plants.

[2]
a.

Define osmolarity. 

[1]
b.

Deduce, with a reason, which red blood cell has been placed in a hypertonic solution.

[1]
c.

State what change there has been in the cell surface area to volume ratio in red blood cell 1.

[1]
d.

Markscheme

a. water molecules are polar
OR
can form hydrogen bonds 

b. cohesion between water molecules allows continuous water columns
OR
cohesion between water molecules allows transpiration stream «to form in xylem» 

c. adhesion of water to the walls of xylem vessel «helps water rise» 

d. water evaporates at environmental temperatures allowing transpiration pull OWTTE

a.

«measurement of» solute concentration of a solution OWTTE

b.

cell 2 because it has plasmolized/lost water/volume has decreased

c.

decreased

d.

Examiners report

[N/A]
a.
[N/A]
b.
[N/A]
c.
[N/A]
d.

Syllabus sections

Core » Topic 2: Molecular biology » 2.2 Water
Show 28 related questions
Core » Topic 2: Molecular biology
Core

View options