Theory and Relation to Cell Biology

University:
York University
Course:
SC/BIOL 2021 | Cell Biology
Academic year:

2023
Views:

317

Pages:

3
Author:

Nick T.

What is a Theory? A theory is a hypothesis that has been tested Critically under many different conditions by different investigators using variety 2 of approaches By the time an explanation is regarded as a theory it is widely accepted by scientists in the field. Hypotheses can be accepted as working theories The 'Solid Ground' of Science Evolution Germ Theory Cell Theory Laws in Science If a theory is throughly tested and Confirmed over many years by Such large numbers of investigators that there is No doubt in its validity it may eventually be regarded as a law ex. Gravity, laws of Thermodynamics, Laws that govern behaviour of gases Biologists are very Conservative about using the term 'law' Since there are likely many new discoveries to come HYPOTHESIS Theory 3 Biologists 'Solid ground' ↓ Law Strands of Cell Biology Ceus are essentially doing Chemistry. In bioenergetics Cell biology and Chem Cross over Modem Cell biology came together in the 1930s; Genetics, Cell bio, Chem 'Strands' of Cell Biology bio-chemistry synthesis of urea in lat fermentation done by cells! genetic code Hooke looks at cork Erown every cell notes comes suclei from a cell glycolysis TICA DNA double helx Dolly the sheep! Most development occured in 19305 cytology 16005 Van Leeuwenhoes looks at fots of things Schleiden & stains & dyes Schwann formulate cell theory electron microscopy DNA sequencing nane- technology! 19305 chromosomes chromesome theory better way of examining Calls genetics DNA Mendel, pea plants Cytology: Light Microscopy Cytology: How the cell looks and what it is able to tell us Cytology-Light Microscopy Unstained Bright Field: Phase Contrast DIC Stained Blood Tissue Shining a white light onto a cell 32 ways of manipulating the quality 3 of lift Starting to see the 3D Structure yet unable to see inside Cells: The Nuclei really show up (purple) Allows you to see the architecture of the cells in different teams and groups -Without the stain it would look like a clear and Colourless siab that gives you no information. Fluorescence Microscopy AKA Dark microscopy Visualizing based on elements in the cell being tagged with molecules that floresc at different wavelengths giving off different Colours. Dyed antibodies of molecules that attach to desired molecules so they will glow Electron Microscopy Scanning Electron Microscopy (SEM) Looking at the external surface of the Cell, tissue, layer, etc. S = Surface Transmission Electron Microscopy (TEM) Looking within the Cells. Can see the 'Slice' of the cell, including being able to see the intracellular organelles T= Through