Cell Structure 3 exam qs ✨

Fig 1.1 is an electron micrograph of xylem tissue in the stem of a plant.
State 1 function of xylem tissue (1)

Fig 1.1 is an electron micrograph of xylem tissue in the stem of a plant.
The Spiral band in the xylem vessel shown in (fig 1.1) contains a substance called lignin.
State the function of this spiral band of lignin AND explain why it is important that the xylem vessel becomes lignified this way (3)

Fig 1.1 is an electron micrograph of xylem tissue in the stem of a plant.
Explain the function of the pits seen in (fig 1.1) (2)

State the maximum magnification that can be achieved by a light microscope and a transmission electron microscope
Select your answers from the list below: 10x 40x 100x (2)

Describe what is meant by the term resolution (2)

Table 4.1 compares the structures of prokaryotic and eukaryotic cells
Complete the table
(table 4.1)
eukaryotic , prokaryotic
no true nucleus, genetic material held in a nucleus
genetic material consists of ‘naked’ DNA, ___
average diameter of cell 0.5-5micrometer, ___
___ ribosomes about 22nm in diameter
___ cell wall sometimes present
(4)

The cytoskeleton is an important component in the cytoplasm of all eukaryotic cells
Name one structure, associated with the cytoskeleton, which can bring about cell movement (1)

The cytoskeleton is an important component in the cytoplasm of all eukaryotic cells
Suggest two processes inside cells that rely on the cytoskeleton for movement (2)

Q3 (fig 1.1) is a diagram of an animal cell as seen using a transmission electron microscope
Name the structures of the cell labelled A B C D (4)

Q3 (fig 1.1) is a diagram of an animal cell as seen using a transmission electron microscope
Structures C and E are examples of the same organelle
Suggest why E looks so different to C
(2)

Q3 (fig 1.1) is a diagram of an animal cell as seen using a transmission electron microscope
Calculate the actual length of structure C
Show your working and give your answer in micrometres (2)

Q3 (fig 1.1) is a diagram of an animal cell as seen using a transmission electron microscope
Proteins are produced by the structure labelled F
Some of these proteins may be extracellular proteins that are released from the cell
Outline the sequence of events following the production of extra cellular proteins that leads to their release from the cell
(3)

Membranes are a fundamental part of the cell.
They are found both at the surface of a cell and inside a cell
State three rolls of membrane inside cells (3)

Cells contain a large number of membrane-bound vesicles. Many of these vesicles transport substances between organelles.
Outline how the vesicles are moved from one organelle to another (3)

The proteins embedded in the membranes of vesicles have different functions
- COPI and COPII proteins are known as ‘address proteins’
- Vesicles that transport materials from the Golgi to the rough endoplasmic reticulum (RER) are coated in COPI proteins
- Vesicles that transport materials to the Golgi from the RER are coated in COPII proteins
Suggest how these proteins ensure that a vesicle is transported to the correct target organelle
(2)

Cells in the pancreas secrete proteins such as the enzymes pancreatic amylase and protease
Describe how these extracellular enzymes are secreted from the cells (2)

(fig 1.1) on insert (refer) shows an electron micrograph of cells from the liver
Some cells, such as liver cells, contain a lot of Golgi apparatus
State one function of the Golgi apparatus (1)

(fig 1.1) on insert (refer) shows an electron micrograph of cells from the liver
Suggest why the nuclear envelope contains pores (2)