Cells are the structural and functional units of all living organisms. Each cell is an amazing world unto itself: it can take in nutrients, convert these nutrients into energy, carry out specialized functions, and reproduce as necessary. Even more amazing is that each cell stores its own set of instructions for carrying out each of these activities. Some organisms, such as bacteria, are unicellular, consisting of a single cell. Other organisms, such as humans, are multicellular, or have many cells.
Most prokaryotes and some eukaryotes (plants and fungi) have a cell wall; a strong structure surrounding the cell and preventing it from bursting in a hypotonic environment. However, the cell walls of prokaryotes and eukaryotes, although similar in function, are made of different types of materials. Both prokaryotes and eukaryotes have a fluid-like matrix that fills the cell called cytoplasm. Both organisms have a supportive cytoskeleton within the cell, although this feature was only recently discovered to occur within prokaryotes. Both prokaryotic and eukaryotic cells can have thin extensions of the plasma membrane supported by elements of the cytoskeleton, including flagella and cilia in eukaryotes and flagella, end flagella, fimbriae and pili in prokaryotes.
I will also include a labelled diagram of a typical cell. Cells Cells are the basic unit of living materials; every individual is made up of billions of cells. Cells vary in size and shape and carry out different functions, but there are three things that can usually be found in any type of cell; nucleus, cytoplasm and membrane (however, a mature red blood cell for example doesn’t have a nucleus so is therefore an exception from this statement). Cells are usually very small and require microscopes for them to be seen. There is only one cell in the body that can be seen with the naked eye, the female ovum.
P2 Outline the Main Tissues Of The Body Epithelial Epithelial tissue is basically the linings of both the internal and external surfaces of the body and can be divided into two groups. The groups depend upon the number of layers of which it is composed. These two groups are simple epithelial and compound. Simple squamous are thin, flat plates and their main function is osmosis (which is the passage of water molecules from a region of low concentration to one of high concentration through a semi-permeable membrane) and diffusion (which is the passage of molecules from a high concentration to a low concentration). They form the lining of cavities such as the mouth, blood capillaries, heart and lung alveoli and make up the outer layers of the skin.
The cytoplasm is also where nutrients are absorbed and processed and is where many chemical reactions take place. Cytoplasm This is a semi-fluid material likened to a gel. It holds together the organelles, apart from the nucleus of the cell and supports the cells structure to make it possible for molecules to be transported. The cytoplasm is also where nutrients are absorbed and processed and is where many chemical reactions take place. Mitochondrion Mitochondria are concerned with energy release.
Lab 4 The Cell: Anatomy and Divison Anatomy of the composite cell 1.Define the following terms: organelle: "small organs"; are the metabolic machinery of the cell, and that are highly organized to carry out specific functions for the cell as a whole. Cell: the structural and functional unit of all living things, is a complete entity. 2.Although cells have differences that reflect their specific functions in the body, what functions do they have in common? Growing, reproducing, and responding to a stimulus are common functioning characteristics amongst all cells. In addition, all cells can maintain their boundaries, metabolize, digest nutrients, and dispose wastes.
Cell Membrane The cell membrane is a thin semi-permeable membrane that surrounds the cytoplasm of a cell. The membranes function is to protect the integrity of the interior of the cell by allowing certain substances into the cell, while keeping other substances out. It is a fluid phospholipid bilayer embedded with proteins and glycoproteins. The phospholipid bilayer is arranged so that the polar ends of the molecules (the portion of the phospholipid that is soluble in water) form the outermost and innermost surface of the membrane while the non-polar ends (the fatty acid portions of the phospholipids that are insoluble in water) form the centre of the membrane Nuclear Membrane It is a double-layered membrane enclosing the nucleus of a cell that controls what enters and leaves the nucleus. It can also be called nuclear envelope.
All organisms that are considered to be alive must possess certain key characteristics or functions. These include: order, response to the environment, reproduction, growth and development, regulation, energy processing and evolution. Since we recognize life by what living things do, these seven characteristics serve to define life. Organisms consist of one or more cells and while they may be very complex they are highly organized and coordinated. Inside each cell, atoms make up molecules.
All living organism are made up of cells. A collection of cells form tissue and tissue forms organs and muscles. These tissues have different structures and functions. Different cells or tissues specialise on different functions. My focus for this essay is about a very vital tissue in our body; the Epithelium.
There are structural and fundamental similarities and differences between plant and animal cells. In general, most of the plant and animal cells are eukaryotic, that’s mean most of them have carry distinct nucleus and membrane-bound organelles such as mitochondria, cytoplasm and vacuole, are generally present in both plant and animal cells. They both go through the process of respiration where they absorb oxygen and release carbon dioxide and energy. Here are the differences between them: Firstly, for the sizes, plant cells’ sizes are relatively larger, while the sizes of animal cells are relatively smaller. Second is the shape of cells.