Quetext About FAQ Contact INTRODUCTION OF CYTOKINES: The term ‘Cytokine’ originates from mixture of two Greek words ‘cyto’ meaning ‘cell’ and ‘kinos’ meaning ‘movement’.These are signalling molecules that help in cell-cell communication in immune response and stimulate the movement of cells toward the sites of infections, trauma and inflamation. Cytokines are composed mostly of peptides, proteins and glycoproteins. These are obtained from a wide range of immune cells such as lymphocytes, macrophages and mast cells as well as fibroblasts, endothelial cells and stromal cells. Types of Cytokines: Following are different types of cytokines: 1. Chemokines: These are the type of cytokines that bring cells to the site of infection utilizing the process
Create a 1 page study guide that will show an understanding of transportation across plasma membranes, cell respiration, and protein synthesis. The plasma membrane surrounding cells is where the exchange of substances inside and outside of cells takes place. Some substances need to move from the extracellular fluid outside cells to the inside of the cell, and some substances need to move from the inside of the cell to the extracellular fluid. Some of the proteins that are stuck in the plasma membrane help to form openings (channels) in the membrane. Through these channels, some substances such as hormones or ions are allowed to pass through.
Activation of the complement cascade triggers opponisation, chemotaxis, inflammation and increased capillary permeability, and cytolysis. Three different pathways can be used to activate the complement system which are the classical pathway, alternative pathway, and mannose-binding lectin (MBL) pathway. The alternative and lectin pathway are initiated by microbes in the absence of antibody. Classical pathways however is initiated by certain isotypes of antibody attached to antigens. Activation of each of the pathways causing the activation of C3, the most abundant complement protein in the plasma, which cleave into C3b, a larger fragment and a smaller fragment C3.
Most actin molecules work together to give support and structure to the plasma membrane and are therefore found near the cell membrane. Can generate locomotion in cells such as white blood cells and the amoeba, to provide phagocytosis. interact with myosin ("thick") filaments in skeletal muscle fibers to provide the force of muscular contraction. [pic] [pic] ● Intermediate Filaments These cytoplasmic fibers average 10 nm in diameter (and thus are "intermediate" in size between actin filaments (8 nm) and microtubules (25 nm). Intermediate filaments play similar roles in the cell: providing a supporting framework within the cell.
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
Structure – The nucleus is encapsulated and protected by the nuclear envelope, which is a double lipid bilayer. Within the envelope is the nucleoplasm, which holds chromatin, a complexity of proteins and DNA, and in the center of the nucleus is the nucleolus. The nucleus also has pores on the outer membrane of the nuclear envelope, which regulate the entry and exit of certain macromolecules (Campbell, 2005, pg.102). Lysosome Function – Lysosomes are membranous sacs filled with enzymes that are used to digest different kinds of macromolecules within a cell (Campbell, 2005, pg.107). Lysosomes are essentially a digestive system for the cell both breaking down materials taken in from outside the cell and breaking down obsolete components of the cell itself (Cooper).
Anatomy & Physiology M and W 6:15–9:15 pm Introduction Many chemical reactions take place in each individual human cell, all performing the necessary functions for such a large, complex, multicellular organism. How do these reactions occur? Chemical reactions involve the breaking and reforming of chemical bonds between molecules (substrates), which are transformed into different molecules (products). Enzymes are biological catalysts. They help to increase the rate of chemical reactions.
These can then be transported in the appropriate form to the cells in the body through the circulatory system. For growth and repair of our cells and tissues energy is required, this is due to the biochemical reactions which build large molecules from simpler ones to occur. This energy is then needed in order to build proteins from amino acids, these are formed through the process of Active transport of substances in or out of our cells happens through this energy made, an example of this would be the transport of amino acids from the small intestine into the blood stream. Active transport often takes place against a diffusion gradient which then allows the body to control its internal environment more efficiently. When we move our body uses energy, this occurs on several levels: • inside our cells – chromosome • whole cells – sperm swimming • tissues – muscles contracting • whole organs – heart beating • part or whole organisms – walking Since the blood found in the human body is warm energy is used in order to maintain the temperature, we use 70% of this energy from respiration to do so and this makes sure the temperature stays at 37
This occurs when a segment of the plasma membrane surrounds a particle or large molecule, encloses it,and brings it into the cell. 1\'10 very important types of endocytosis are phagocytosisand pinocytosis. During phagocytosis, cellular projections called pseudopods engulf particles and bring them into the cel1. Phagocytosis is used by white blood cells to destroy bacteria and foreign substances (see Figure 16.8, page 461, and further discussion in Chapter 16). In pinocytosis, the plasma membrane folds inward, bringing extracellular fl uid into the cell, along with whatever substances are dissolved in the fluid .
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.