[Maximum number: 1]

The electron micrograph shows onion root cells prepared using a freeze-fracture technique. The cells were quickly frozen and then physically broken apart. Freeze fracture breaks apart cells along weak areas, such as membranes and the surfaces of organelles.

$\times 20000$

Which statement best explains the appearance of the electron micrograph?

The cells were broken apart at the endoplasmic reticulum; structure X is a ribosome.

The cells were broken apart at the nuclear envelope; structure X is a nuclear pore.

The cells were broken apart at the nuclear envelope; structure X is a ribosome.

The cells were broken apart at the tonoplast; structure X is a plasmodesma.

[Maximum number: 1]

Which row shows the correct order of size of these cell structures?

1 width of a mitochondrion
2 width of a ribosome
3 width of a cell surface membrane
4 width of a chloroplast

largest

smallest

[Maximum number: 1]

The photomicrograph shows the ultrastructure of part of a cell.

Which statement about the type of cell shown in the photomicrograph is correct?

It is a plant cell because it has both chloroplasts and a nucleus.

It is a plant cell because it has chloroplasts.

It is an animal cell because it has a cell membrane.

It is an animal cell because it has mitochondria.

[Maximum number: 1]

Which cell structure contains cytoplasm?

chloroplasts

mitochondria

plasmodesmata

smooth endoplasmic reticulum

[Maximum number: 1]

A student made notes describing photomicrographs of four cells.
cell 1 Grey cytoplasm at edge of cell contains many black lines and spots. Large white area in centre of cell.
cell 2 Grey cytoplasm contains many black lines and spots which fill the entire cell.
cell 3 Pale blue cytoplasm surrounds a single dark blue spot.
cell 4 Many green structures are enclosed within a rectangular shape with visible boundaries.

Which table identifies the type of cell and the type of microscope used to take each photograph?