Microscopy and Cell Specialisation
Light microscopes are your everyday lab equipment - cheaper, easier to use, and you can observe living samples in colour. Electron microscopes are the high-tech option with much better resolution, but samples must be dead and they're expensive. The key formula you need is: Image Size = Actual Size × Magnification.
When preparing microscope slides, you'll peel off a thin layer of tissue, add iodine solution as a stain, and carefully place it on the slide without air bubbles. Always start with the lowest objective lens and gradually increase magnification.
Stem cells are the ultimate shape-shifters - unspecialised cells that can become anything. Differentiation is when these cells specialise for specific jobs. Embryonic stem cells can become any type of cell, whilst adult stem cells (found in bone marrow) are more limited.
Specialised cells are perfectly designed for their jobs. Sperm cells are streamlined with lots of mitochondria for energy and enzymes to digest egg membranes. Nerve cells have a myelin sheath for insulation and dendrites to connect with other nerves. Muscle cells contain protein fibres that can change length and are packed with mitochondria for energy.
Remember: Plant stem cells are found in meristems and can differentiate throughout the plant's life, unlike animal stem cells which are mainly active during the embryo stage.