Sliding Filament Mechanism By Mindy Istas The sliding filament mechanism is described as a process used to contract muscles. There are key components within the muscle that include myofibrils which consist of two types of protein filaments called thick and thin filaments. The thick and thin filaments have different structures that enable them to work together. Myosin and actin are also a key element to help the thick and thin filaments bind together. ATP is also a key element to the process of the sliding filament mechanism.
Signal transduction happens when a membrane protein may have a binding site with a specific shape that fits the shape of a chemical messenger, such as hormones & other extracellular substances that trigger changes in cellular activity. Another function is cell to cell recognition which occurs when some proteins serve as identification tags that are specifically recognized by other cells. The Cell Wall is a rigid structure mainly made out of the protein cellulose, a tough chemical that helps plants to maintain their shape
Intermediate filaments play similar roles in the cell: providing a supporting framework within the cell. Provide support for microfilaments and microtubules by holding them in place. There are several types of intermediate filament, each constructed from one or more proteins characteristic of it. • keratins are found in epithelial cells and also form hair and nails; • nuclear lamins form a meshwork that stabilizes the inner membrane of the
The space between the outer and inner membranes can fill with newly synthesized proteins just as the rough endoplasmic reticulum does. The nuclear envelope is enmeshed in a network of filaments for stability. Phospholipid Bilayer Both the cell surface membrane and the membranes surrounding certain organelles have the same basic structure. Much of the membrane is made up of what is known as a Phospholipid bilayer. The phospholipids are arranged in two layers (a bilayer).
There are many molecules within cells and organisms that must have complimentary shapes that fit together in order for them to carry out their function. One type of molecule for which this is extremely important is enzymes. There are two models that demonstrate how this may work, the first of which is the lock and key model in which the substrate and enzyme binding site have complimentary shapes so that the substrate or subtrates fit perfectly into the enzyme, which joins or separates them. The second model, the induced fit model, is similar, however the enzyme moulds its shape to match the substrate. There are many processes in which it is important that these shapes fit, for example DNA helicase, RNA polymerase and DNA polymerase must all have the correct shape in order for DNA strands to separate, mRNA to form and DNA to then rejoin during polypeptide synthesis.
In synovial joints a fluid containing joint cavity separates the bones. The opposing bone surfaces in the joint cavities are covered with a layer of cartilage. Outside the joint cavities ligaments connect the bones. In addition to being held together by ligaments, synovial joints are also stabilized by the muscles around the joints. | How Do They MoveWith a lot of help.
Which include fats, oils, waxes, and cholesterol. They are mostly made up of long chains of monomers. Which is also known as fatty acids. Proteins are polymers made from monomers called amino acids. Which are building blocks of life.
Embedded in the plasma membrane are protein molecules, some of which form channels through which other molecules can pass. Some proteins act as carriers — that is, they are “paid” in energy to let a molecule attach to itself and then transport that molecule inside the cell. A membrane can allow molecules to be passively transported through it in three ways: diffusion (high concentration to a low concentration), osmosis (water
Enzymes are proteins folded into complex shapes that allow smaller specific molecules to fit into them like a lock and key. The place where the substrate molecules fit is called the active site; chemical reactions occur at the active site. Catalase is found in all cells and protects them from a dangerous waste chemical called Hydrogen Peroxide. It breaks the hydrogen peroxide down to water and oxygen The substrate (hydrogen peroxide) and the catalase molecules are continuously on the move. Every so often they will collide so that the substrate molecule(s) fits into the enzyme's active site.
Fibrous or fixed joints (immovable) Cartilaginous joints (slightly moveable) Synovial joints (freely moveable) Where do joints form? Joints which are also called articulations are formed where the surfaces of two or more bones meet and articulate together. Bones are connected to each other by fibrous tissue (ligaments) which allows movement and flexibility and the tendons attach the muscles to the bone. Synovial joints can be determined by their shape and the amount of movement they have as seen in fig 1.6 Fig 1.6 Synovial joints Boyle & Senior Human Biology 3rd edition Synovial joints. A