Mechanisms for the Regulation of Biological Processes

• Enzymes bind to a substrate (anything that needs to be changed into something else [molecule, protein etc.])

gluconeogenesis slow down in which release of glucose to the blood stream is also slowed down

(a) Describe THREE types of chemical bonds/interactions found in proteins. For each type, describe its role in determining protein structure.

either maintain or amplify important chemical systems. This could happen at a molecular level to coordinate the function of a single enzyme or it could happen throughout the body to regulate the organism’s

enable the substrate to bind to the enzyme and form the enzyme substrate complex and

The basic building blocks of proteins are amino acids, the biuret reaction tests for protein. A solution of sodium hydroxide is added to a sample then a few drops of copper sulphate solution, if positive – the solution will turn mauve. There are 20 different amino acids and they can be joined in any order. Therefore there can be many different functions. A protein consists of one or more polypeptide chains (a polypeptide chain being multiple amino acids joined together via condensation, producing a peptide bond). Different proteins have different shapes as the shapes are determined by the sequence of amino acids.

Proteins are complex structures made up of chains of amino acids. Each protein has a different function such as enzymes to catalyze reactions or protein hormones to trigger certain functions of a cell. First let’s start with the most basic component of a protein: an amino acid. An amino acid is made up of a central carbon atom attached to a hydrogen atom, a carboxyl group, an amino group, and an R group which varies

A phosphorylation cascade is a sequence of actions, where one enzyme phosphorylates another, causing a chain reaction, leading to the phosphorylation for thousands of other proteins. This has told in signal transduction of hormone messages. The first step, signal molecule stimulates the receptor molecule. In turn, activates relay molecule. The ligand binding the receptor protein in the cell membrane, activating a relay protein, which in turns triggers other inactive protein complexes through adding a phosphate group and hydrolyzing ATP to produce energy. The kind of enzymes carry out phosphorylation is kinases. Next in the second step, triggered relay molecule activates inactive kinase 1. Active kinase 1 phosphorylates inactive kinase 2, activating

For AP Biology I chose cell signaling because I had worked with a friend to complete this assignment. We needed to remain curious in

Since enzymes are biochemical catalysts, made up at least partially of protein, they are sensitive in varying degrees to heat. Raising temperatures of the environment generally multiplies the degree of activity by the enzyme. Once an optimum temperature has been reached, however, temperatures that are too high will denature the enzyme it will loose its ability to function. Cofactors are agents that are necessary for an enzyme to carry out a transformation. An apoenzyme is the enzyme without the cofactor and the holoenzyme is the active species made by combining the cofactor with the apoenzyme. The coenzymes are small organic molecules that are non-peptide in nature and are sometimes also known as a prosthetic group. Vitamins are small organic molecules that act as coenzymes although not all coenzymes are vitamins. A vitamin is a molecule that cannot be produced within the body and must be introduced i.e. through diet. Another example of enzyme regulation is that of competitive inhibitors. If a reversible inhibitor can bind to the enzyme active site in place of the substrate, it is described as a "competitive inhibitor." In pure competitive inhibition, the inhibitor is assumed to bind to the free enzyme but not to the enzyme-substrate complex. When a non-competitive inhibitor binds to the enzyme at the regulatory site, the shape of the active site changes so that it can no longer bind its substrate or catalyze the production of

The new phosphate group alters the role of the protein: it can activate, deactivate, or cause a

These proteins often utilize ATP-dependent chromatin remodeling complexes to help them tighten or loosen the chromatin as the protein complex performs its job.

In order to remain alive, the body must maintain a constant internal environment, despite internal and external stressors, within the body’s limits. Bodies maintain an equilibrium of gas concentrations, temperature, pressure, pH levels, nutrients, and water levels; called homeostasis. There are two mechanisms involved in homeostasis, negative and positive, whose purpose is to return the body back to normal after any stressors. Feedback mechanism

The pathophysiology of hypertension (HTN) is best explained clearly if you have an understanding of how blood pressure (BP) works in the body. BP is seen as the function of both cardiac output (CO) in the human system and systemic vascular resistance (SVR). Cardiac output (CO) is made up of both heart rate (HR) and stroke volume (SV). SV in turn depends on contractility and preload of the system. SVR relies on contractility and afterload. There is literature that supports molecular and cellular levels relating to effects on blood pressure in terms of genetic make-up. Changes in any of these processes have the ability to alter CO or SVR, causing BP alteration and HTN.

Cell signaling in the central nervous system refers to the communication that occurs in cells to coordinate* cell actions, as the cells receive and respond to other cells to help with many functions in the body, from immunity to development to growth.