Please enable JavaScript.
Coggle requires JavaScript to display documents.
A Tour of Cells - Coggle Diagram
A Tour of Cells
-
Microscopy
In Lm, light passes through a specimen and the through a glass lenses. The lenses refracts light so that the image is magnified?
The resolution of standard light microscopy is too low to study organelles, the membrane-enclosed structures in eukaryotic cells
Two basic types of electron microscopes are used to study subcellular structures.
Scanning electron microscopes focus a beam of electron onto the surface of a specimen providing images that look 3-D.
Transmission electron microscopes focus a beam of electrons through a specimen.
-
Cell Fractionation
They take apart and separate the major organelles from one another. Centrifuges fractionate cells into their component's parts. It also enables scientists to determine the function of organelles
-
The Nucleus
It contains most of the cells genes and it's usually the most conspicuous organelles. Nuclear envelope encloses the nucleus, separating it from the cytoplasm. The envelope is also a double membrane; each membrane consists of a lipid bilayer
Nuclear Lamina is composed of proteins, and it maintains the shape of the nucleus. Pores, lined with a structures called a pore complex, regulate the entry and exit of molecules from the nucleus
-
Vacuoles
They are large vesicles derived from the Er and Golgi apparatus. They perform a variety of function in different kinds of cells.
Food vacuoles: are formed by phagocytosis.
Contractile vacuoles: are found in many freshwater protests, pump excess water out of cell.
Central vacuoles: are found in many mature plant cells, contain a solution called sap
Ribosomes
They are complexes made of ribosomal RNA and protein. It is also build proteins in two location: In the cytosol, AND On the outside of the endoplasmic reticulum or the nuclear envelope
The Golgi Apparatus
It consists of flattened membrane sacs called cisternae. It also modifies products of the ER, and Manufactures certain macromolecules
Lysosomes
Is a membrane sac of hydrolytic enzymes that can digest macromolecules. Lysosomal enzymes work best in the acidic environment inside the lysosome. Some lysosome probably arise by budding from the trans face of the Golgi apparatus