Cell structure and organellesIB MYP Biology: Mind map

Exam questions on Cell structure and organelles

1. A sports scientist is studying cells taken from the leg muscle of a marathon runner and from the lining of the runner's cheek. Under the microscope she sees that the muscle cells contain far more mitochondria than the cheek cells.
   Explain why the muscle cells contain many more mitochondria than the cheek cells.2 marks
2. A student compares a cell from the leaf of a pondweed plant with a cell from the lining of a human cheek. The pondweed cell has a rigid, regular outline, large green structures and a large fluid-filled space. The cheek cell is irregular in shape and has none of these features.
   Describe the function of the chloroplasts and of the cell wall in the pondweed cell.2 marks
3. A student wants to find out whether cells in different parts of a plant contain different structures. She makes microscope slides of a green leaf and of a white root from the same potted plant and views both with a light microscope. She notices that the leaf cells contain many green structures but the root cells seem to contain none.
   State a testable hypothesis about the number of chloroplasts in leaf cells and root cells, with a scientific reason, and identify the independent variable.3 marks