Cell Structure & Organisation (Edexcel A (SNAB) A Level Biology)

A student drew a eukaryotic cell based on what they saw in an electron micrograph.

Identify F and H in the student's drawing.

The student concluded that the eukaryotic cell in part (a) was not a plant cell.

State two reasons why they came to this conclusion.

Which of the following is a characteristic shared by mitochondria and prokaryotes? 

Certain cells such as muscle cells contain more mitochondria than cells used for storage (such as adipose/fat cells).

Explain the reason for this.

The following electron micrograph shows an organelle found within a cell.

Identify the organelle visible in the micrograph and provide a reason for your answer.

(2)

Explain why an electron microscope was used to obtain this image instead of a light microscope.

(2)

Compare and contrast a transmission electron microscope/TEM with a scanning electron microscope/SEM.

The following diagram shows part of a plant cell as seen with an electron micrograph.

Calculate the actual diameter of the cell. Show your working and give your answer to three significant figures.

The following image was created using a transmission electron microscope.

Identify whether these are prokaryotic or eukaryotic cells and give one reason for your answer.

Draw a labelled biological diagram of cell X in the diagram at part (a).

Prokaryotic and eukaryotic cells have several structural differences between them.)

Which of the following is not a difference between prokaryotic and eukaryotic cells? 

In multicellular organisms, cells will often become specialised.

Explain the importance of specialised cells in a multicellular organism.

(2)

Which of the following is an example of tissue? 

(1)

A student used a light microscope to view a specimen. They wanted to use the stage micrometer and eyepiece graticule to determine the actual size of the specimen.

Explain why both a stage micrometer and eyepiece graticule is needed.

A stage micrometer with small divisions of 0.1 mm was placed over the eyepiece graticule as shown in the diagram below.

Plant tissue was viewed under the microscope and one of the cells spanned across 20 eyepiece graticule units.i)

Which of the following represents the actual size of this cell? 

Explain why adjustments must be made to the eyepiece graticule and stage micrometer when the specimen from part (b) is viewed under a more powerful objective lens.

A student is given an unknown tissue sample.

Describe how they would use microscopy to determine the type of tissue in this sample.