Chapter 2- Basic Componants of Living Organisms Flashcards
In Which Centuries was the light microscope invented?
16th and 17th century
What does the Cell Theory state?
- Both plant and Animal tissue is composed of cells
- Cells are the basic unit of life
- Cells only develop from existing cells
How many lenses does a light microscope have?
2
Calculate the magnification used to measure a nucleus in a plant cell that is 0.6um in real life and measured 1.2mm down the microscope.
x2000
Convert 56.3nm into cm.
5.63x10^-6
Name the 2 types of electron microscopy.
SEM and TEM
Compare and Contrast Light and Electron Microscopy.
- An electron microscope is very expensive to buy and requires special environments. This makes it expensive to maintain. In addition, it requires high technical skills to use and is therefore limited to specialized use such as research. A light microscope, on the other hand, is cheap to buy and maintain. It requires no special skills to use. As a result, it is suitable for most basic functions, and is very common in schools and other learning institutions.
- While a light microscope uses light to illuminate specimens and glass lenses to magnify images, an electron microscope uses a beam of electrons to illuminate specimens and magnetic lenses to magnify images.
- The resolution (the level of image detailing) is the main difference between these two microscopes. A light microscope has a resolution of up to 0.3µm, i.e. 3 micrometers. This limits it as two close objects cannot be seen as separate. In an electron microscope, the resolution is about 0.0001µm, i.e. 0.01 nanometers. This resolution can be used in situations that require greater details, such as studying cell nuclei.
- A light microscope can be used to view both dead and live specimens. This makes it important in studying live ones. By contrast, an electron microscope cannot be used to view living specimens as it uses electrons that are destructive to life.
What is an artefact?
A visible structural detail caused by processing the specimen and not a feature of the specimen
Give an example of one artefact you might find when using a light microscope.
Air Bubbles trapped when putting the cover slip on.
Give the function of the Nucleolus
Responsible for Producing Ribosomes
Give the function of the Mitochondria
Site of the final stages of cellular respiration
Give the function of the Vesicles
Membranous sacs that store and transport materials inside the cells.
Give the function of the Lysosomes.
Contain enzymes for the breaking down of waste material and pathogens
Name the 3 elements that make up the Cytoskeleton
- Microfilaments
- Microtubules
- Intermediate Fibres
What are Centrioles?
Another element of the Cytoskeleton found in eukaryotic cells (except flowering plants and fungi) Composed of Microtubules. 2 form the centrosome, which makes the spindle fibres for cell division.
