University:
California State University, Northridge
Course:
CJS 320 | Introduction to Criminal Law and Legal Analysis
Academic year:

2024
Views:

61

Pages:

2
Author:

Peggy D.

Course : Biology Lecture : Hary Credit Hours : 3 Credits Semester Sessions : 3 Semester, 2021/2022 Session Prepared By : Pegyy Dania LECTURE NOTES Cell Concepts and Theory British scientist Robert Hook on 1665 English scientist Robert Hook in 1665 observed cork incision vial using a microscope simple, He saw a structure like the bee house was then given the name "cell" (cellula (Latin) = small chamber. He too states that each part is looks bounded by walls, which it isn't another is the existing cell walls death of the plant. Science that studies cells is cytology. Knowledge about Cell structure and function continue to develop up to now, along with techniques and the analytical equipment used is good in vitro and in vivo. At first scientists could observe various types of plant and animal cells as well as singlecelled organisms. After 1830s it was understood that all living creatures, both plants and Animals are composed of cells, based on Mathias Schleiden's findings on cells plants and discoveries of Theodor Schwan in animal cells, which is further known with cell theory. These statements are in above is known as the cell theory consisting of: 1. Every living creature consists of one or more cells 2. Cells are structural units and function of all living things. Cell is the smallest unit of living things especially in organisms multicellular. 3. All life originates from cells previously through division 4. Cells contain genetic material which will be handed down to generation through division. The proposed theory shows that the cell is structural unity of living things. Cell as the smallest structural unit implies that cells are a fundamental constituent of the body living things. It is known that there are living creatures which consists of one cell and is called unicellular organisms, and some are composed of many cells and is called as a multicellular organism. Cell shape and size vary. Prokaryotic cells have a shape simple, for example shaped bacteria round, rod, or spiral. Eukaryotic cells their shapes vary greatly, for example cells Some plants are shaped like bullets, cubes, prisms, and fibers. Normal cell shape adapted to its function, for exampleEpidermal cells are flat and arranged The meeting serves to protect cells/tissues that are on the inside, cells Nerves have cytoplasmic projections long in the form of dendrites and axons serves to transmit impulses to long distance. Learn the shape of cells others in relation to suitability with its function. Cell sizes vary, on generally very small usually only a few microns, and can only be seen by using a microscope. Cell Amoeba has an average size of  300 m (1m = 0.001 mm). Exceptions to cells eggs, fibrous cells (several hundred mm), and sap cells (several meters), generally relatively larger in size big/long and can be seen with eye without using a microscope. CellProkaryotic cells generally measure 1-10 m, while eukaryotic cells generally measuring 10 to 100 m.