BIOL 1020 Lecture 6: Lecture 6

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1020
• Professor: Joy Stacey

Document Summary

Backbone of nucleic acid is sugar-phosphate units with bases as appendages. 3" end and 5" end- backbones run in opposite directions antiparallel . Adenine pairs with thymine and guanine pairs with cytosine: hydrogen bonds form between bases. Sequences of nucleotides in dna molecules are passed from parents to offspring. Basic structural and functional unit of every organism. First observed by hooke and leeuwenhoek in late 1600s. (with the first light microscopes- looking at cork trees- first cells) Light microscope (lm) visible light passes through specimen and then through glass lenses, when magnifying the image: 1000x. Electron microscope: used to study subcellular structures: organelles. Scanning electron microscope (sem: focuses a beam of electrons onto surface of specimen o 3d images of cells. Transmission electron microscope (tem: focuses a beam of electrons through a specimen o used to study the internal structure of cells, in 2d. Semi-fluid substance called cytosol inside plasma membrane -