Observing Mitosis (Cambridge International AS Biology)

Mitosis in Root Tips: Observing & Drawing

Spec point — 5.2.2 · interpret photomicrographs, diagrams and microscope slides of cells in different stages of the mitotic cell cycle and identify the main stages of mitosis

• Growth in plants occurs in specific regions called meristems

• The root tip meristem can be used to study mitosis

  • The root tip meristem can be found just behind the protective root cap
  • In the root tip meristem, there is a zone of cell division that contains cells undergoing mitosis

• Pre-prepared slides of root tips can be studied or temporary slides can be prepared using the squash technique (root tips are stained and then gently squashed, spreading the cells out into a thin sheet and allowing individual cells undergoing mitosis to be clearly seen)

Micrograph showing a stained root tip

Analysis

Micrograph showing a cell undergoing prophase (P) and telophase (T)

Micrograph showing cells undergoing metaphase (M) and anaphase (A)

Micrograph showing cells undergoing metaphase (M) and anaphase (A)

Micrograph showing a cell undergoing anaphase (A) and telophase (T)

Exam Hint It is important to be able to recognise each mitotic stage from electron micrographs and to be able to explain why that cell is in the stage you have selected.