Biology – Patterns in Nature

Biology Pattern in disposition 1. Organisms are made of cellular phones that have similar structural characteristics 1. 2. 1Outline the Historical increase of the cell possibility, in particular, the contributions of Robert Hooke and Robert Brown. 1665 English scientist Robert Hooke utilise microscope to examine thin slices of dock and saw small box-like compartments he called cells. He was first to realise ingraft material had organised structure at microscopic level. ( compound microscope) 1831 Scottish phytologist Robert Brown was involved in a dispute about how pollination and fertilisation occurred in plants.During his study with orchids, he noted that Each cell has a spherical structure. He named it the nucleus of a cell. scratch to introduce the concept of a nucleated cell as building block of structure in plants. 1. 2. 2Describe evidence to support the cell theory. Cell theory evidence accumulated over 600 years with advancement of technology with the microscope an d lenses. fourteenth century Italian monks invented magnifying glass spectacles. 1590 first two lens/ compound microscope made by Hans and Zacharias Janssen. 1676 Leeuwenhoek (Dutch) saw micro organisms under a microscope in a drop of pond water. 1824 Henri Dutrochet (French) suggested that all organisms are composed of cells. 1838 Schleiden and Schwann (German) merely advanced idea that all organisms are made of cells.Increasing evidence. E. g. first investigator to view single yeast cells budding and producing new cells. From that time on, cells regarded as building block of life. 1859 Rudolph Virchow (German) stated that all cells divide and that is how new cells are made. 1879 Walther Flemming (German) use biological stains to view cells dividing and verified the ideas of Virchow. 1. 2. Discuss the significance of technical advances to developments of cell theory Middle ages- Spontaneous generation- mall + maggots, tadpoles/frogs in H20. (Living librate arises from non-livin g matter. Problem= the source of new life/ eggs could not be seen, too microscopic. Magnifying lens made in 1300 but not used in astronomical instruments and microscopes until 1600s. Earliest microscope was single lens. Compound was developed shortly after, had 2 lens, objective and an ocular- mounted in a tube. It wasnt until 1660s before developed enough to be useful. Eye can only when be 10cm close to an object to be able to see it in focus.Closer than that the eye cannot resolve or separate small objects so blurred. gag law= to see objects as separate and distinct. Magnifying lenses spread light rays so they get into the eye lens at a oftentimes greater list of incidence than unaided eye. Magnification= to make things appear bigger. Not much development happened for 200 years in microscope advances due to problems with chromatic aberration. Schwann helped to fragment theory of spontaneous generation by magnifying 400 times meat extracts through which hot air had passed. I t was found meat was sterile. Also used microscope to trace presence of yeast in grape juice and beer.