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Biology lab Session 4 Using the light microscope to observe Eukaryotic cells Eukaryotic cells Eukaryotic cells are defined as cells containing organized nucleus and organelles which are enveloped by membrane-bound organelles....
Biology lab Session 4 Using the light microscope to observe Eukaryotic cells Eukaryotic cells Eukaryotic cells are defined as cells containing organized nucleus and organelles which are enveloped by membrane-bound organelles. Examples of eukaryotic cells are plants, animals, protists, fungi. Their genetic material is organized in chromosomes. *Main parts of eukaryotic cells are: Nucleus Golgi apparatus Mitochondria Ribosomes They are much larger and much more complex than prokaryotic cells. Plant cell What are the main different between plant cell and animal cell - cell wall -chloroplast Plant cell: Is the basic unit of all plants. Plant cells, like animal cells, are eukaryotic, meaning they have a membrane-bound nucleus and organelles Unlike animal cells, plant cells have a cell wall surrounding the cell membrane. Although often perceived as an inactive product serving mainly mechanical and structural purposes, the cell wall actually has a multitude of functions upon which plant life depends. Plant cell walls are composed of cellulose, which sets them apart from other organisms with cell walls, such as bacteria (peptidoglycan) and fungi (chitin). Chloroplast Plant cells can be distinguished from most other cells by the presence of chloroplasts, which are also found in certain algae. A chloroplast is a type of plastid (a saclike organelle with a double membrane) that serves as the site of photosynthesis, the process by which energy from the Sun is converted into chemical energy for growth. Chloroplasts contain the pigment chlorophyll to absorb light energy. In plants, these essential organelles occur in all green tissues, though they are concentrated particularly in the parenchyma cells of leaves. Another important characteristic of many plant cells is the presence of one or more large vacuoles. Vacuoles are storage organelles, and those in plant cells enable them to attain a large size without accumulating the bulk that would make metabolism difficult. الرسم مهم Plant cell *Lab works: The preparation by students of an isolated plant cells from onion and observe cells on microscope. Plant Cell components: 1. Cell wall: is the outer most rigid covering of the plant cell. It is a feature of plant cell. 2. Cell membrane: or the plasma membrane is the outer lining of the cell inside the cell wall. 3. Cytosol or cytoplasm: is the gel-like matrix inside the cell membrane which constitutes all cell organelles. 4. Nucleus: is the control center of the cell. It is a membrane bound structure which contains the material of the cell - the DNA 5. Chloroplast: is a plastid with green pigment chlorophyll. It takes light energy and converts it to chemical energy by the process of photosynthesis. 6. Mitochondria: carries out cellular respiration and provides energy to the cells. 7. Vacuoles: storage center of the cell. 8. Golgi body: is responsible for storing, packaging of cellular products. 9. Ribosomes: are made of RNA and proteins, and are sites for protein synthesis. 10. Endoplasmic reticulum: it’s composed of rough and smooth are responsible for synthesis large groups of proteins and lipids
