BIOL 2070H Lecture Notes - Lecture 1: Meiosis, Cholesterol, Optical Microscope
Document Summary
Living things: are highly organized, display homeostasis, capable of self-reproduction, grow and develop from a simple beginning, take energy from the environment and transform it, respond to stimuli, show adaptation to their environment. Evolution of all cells can be traced back to one ancestor: ancestral prokaryotic cell. Light microscope can visualize eukaryotes and most prokaryotes. For stronger magnification an electron microscope is used: can be used to visualize molecules and some atoms. Prokaryotes are simple but show high variation: bacteria & archaea, small and uncomplicated, capable of doing all things living things do, bacteria come in different shapes. Spherical, rod-shaped, spiral: all things floating in cytoplasm no membrane-bound organelles. Cell wall of bacteria contains peptidoglycan: gram positive on the surface. When stained - purple: gram negative deeper in the cell. Eukaryotic cells are more complex: membrane-bound organelles. Nucleus, mitochondria, chloroplasts, vesicles, and endoplasmic reticulum all have lipid bilayer containment.
