Cell Membrane- A semi permeable membrane that surrounds the cytoplasm.
The function of a cell membrane is to protect it from harmful things on the inside and out. It is a phospholipid bilayer that is covered in proteins. It is selectively permeable which means that it only lets what it wants in, kind of like a club bouncer. It is a thin layer (made of phospholipids) that covers the cytoplasm and in plant cells is covered by the cell wall. Cell Wall - a rigid layer of polysaccharides lying outside the plasma membrane of the cells of plants, fungi, and bacteria. In the algae and higher plants, it consists mainly of cellulose. The cell wall is located outside the cell membrane and provides these cells with structural support, protection and is acting as a filtering mechanism. Cell walls are a layer thicker than the cell membrane layer, it is made of cellulose surrounding the cell membrane. Centrioles: Two small organelles that hang out by the nucleus of the cell; they occur in pairs and are involved in the development of spindle fibers in cell division. The main function of the centriole is to help with cell division in animal cells. The centrioles help in the formation of the spindle fibers that separate the chromosomes during cell division which is mitosis. The centrioles are made of microtubules- a microscopic tubular structure present in numbers in the cytoplasm of cells, sometimes aggregating to form more complex structures. Chloroplast- a plastid that contains chlorophyll and in which photosynthesis takes place. The main role is to conduct photosynthesis, where the photosynthetic pigment chlorophyll captures the energy from sunlight, and stores it in the energy storage molecules such as ATP. As well as in making sugars, chloroplasts are important in making other essential plant products, such as fats, oils, scents, and proteins. Chloroplast look like miniature green satellites, the organelles are 3-4 micrometers in diameter. made of 2 membranes and contains thylakoid and stromaon the inside. Fun fact: the concave (the side that looks like it has a dent) side of the chloroplast faces the sunlight. |