For each of the three named cell structures, add a label line on Fig. 1.1 and place the correct letter beside it. • nucleolus = N • tonoplast = T • chloroplast = C
The drawing in Fig. 1.1 is 2000 times larger than the actual size of the cell. Describe the procedure you would use to work out the cell’s actual diameter in micrometres ($\mu\text{m}$), at $X$-$Y$.
Fig. 1.1 was produced using the high power objective lens of a light microscope. Several structures visible in Fig. 1.1 show that the cell is eukaryotic. If the same cell were viewed with an electron micrograph, more cell structures would be seen that occur in eukaryotes but not in prokaryotes. List two examples of these extra cell structures.
State, with reference to water movement from the xylem to the spongy mesophyll cells in the leaf, what the apoplastic pathway means.
Outline which properties of water help it move apoplastically to the spongy mesophyll cells and also into the intercellular air spaces.
Describe the fate of the water vapour in the intercellular air spaces during the day, and explain the reason for this.