Microscopy and Cell Division
This page delves into microscopy techniques and the process of cell division, which are crucial topics for GCSE Biology and advanced biology courses.
Microscopy Techniques
The text explains different microscopy techniques and their applications in cellular biology.
Definition: Magnification is calculated as the size of the image divided by the size of the real object.
The document provides a scale of measurements used in microscopy:
- Centi (cm): 10^-2
- Milli (mm): 10^-3
- Micro (μm): 10^-6
- Nano (nm): 10^-9
Two main types of microscopes are discussed:
- Light microscope: Used to view individual cells and large subcellular structures like the nucleus.
- Electron microscope: Uses a beam of electrons to achieve higher resolution, allowing visualization of smaller structures like mitochondria, chloroplasts, ribosomes, and plasmids.
Highlight: The electron microscope provides much higher resolution than the light microscope, enabling the study of minute cellular structures.
Cell Division
The text explains the process of cell division, focusing on mitosis.
Vocabulary: Chromosomes - Structures in the cell nucleus made of coiled DNA molecules, containing genetic information and found in pairs.
The cell cycle is described as a series of stages during which:
- The cell grows and increases its number of subcellular structures.
- DNA replicates to form two copies of each chromosome.
- During mitosis, one set of chromosomes is pulled to each end of the cell, and the nucleus divides.
Example: In mitosis, the genetic material is doubled and divided into two identical cells, which is crucial for growth and repair in organisms.
This section provides essential information for understanding microscopy techniques and cell division for GCSE Biology exams and beyond.
