Biology - B1 Notes

Cells and Microscopy

• Animal and plant cells both have a cell membrane, cytoplasm, nucleus, mitochondria and ribosomes
• Plant cells have a cell wall, permanent vacuole and chloroplasts and animal cells don't
• Animal cells contain genetic material in the nucleus and bacteria cells have genetic material in rings of DNA called plasmids or float freely in the cytoplasm
  
• Bacteria cells are prokaryotes
• An electron microscope gives a higher resolution

Differentiation and Division

• Cell differentiation is the process by which cells change to become specialised. As cells change, they develop different subcellular structures
• A sperm cell is adapted for swimming to an egg cell in three ways: it has a long-tail and streamlined head to swim, mitochondria for energy and enzymes to digest through an egg cell membrane
• Nerve Cell - carry electrical signals (they have long branched connections to cover the distance  in the body and to form a network)
• Chromosomes are found in a nucleus. They contain genetic…