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Metabolism is the process of extracting nutrients from organic compounds for cell utilization in growth, repair, maintenance, and reproduction. There are two types of reactions: catabolic and anabolic. Catabolic reactions break down organic compounds into smaller molecules to release ATP in respiration– an example is digestion. In anabolic reactions, smaller molecules are combined to form larger organic compounds using ATP – examples are carbon fixation, bone growth and nucleotide synthesis. Anabolism is fueled by catabolism, where catabolic reactions releases ATP for which anabolic reactions utilize to build organic compounds.

Reactions in metabolism are mediated by enzymes, globular proteins that catalyzed biochemical reactions by lowering activation energy. Enzymes take part in metabolic pathways, where they convert larger molecules into a smaller form that can be used by the cell. They are important in metabolism because they couple breaking down compounds with respiration, speed up biochemical reactions and have a regulatory function. Key chemicals that are involved in metabolism are: carbohydrates, lipids, proteins and nucleotides.

Regulation of catabolism and anabolism occur in homeostasis where hormones and neurotransmitters send signals. The signals can increase or decrease enzyme activity, and athe rate of the whole metabolic pathway. There are two types of control: intrinsic and extrinsic. Intrinsic control is when self-regulation is applied when the concentration of products or reactants passes threshold, whilst extrinsic control is when the whole metabolic pathway is altered. An example of a regulatory hormone is cortisol. 

Zinc's role in biological health

Zinc is a metallic element which exists in micro-quantaties in the human body. However, deficiencies in zinc have been linked to a host of different diseases. What characterizes a deficiency in zinc? How widespread is the global prevalence for zinc deficiency and what are some possible causes? What are some sources of zinc foun

Scientific Methods, Atoms, Chemical Bonds & pH Scale

1.List and explain each step of the scientific method. Give an example of an observation that can be evaluated by the scientific method and use the method to explain the observation. Must be at least 250 words. 2.Compare and contrast covalent bonding and ionic bonding. Why do some atoms bond covalently and others ionically? M

Ketone Bodies Metabolism

What are the ketone bodies? Why do they have that name, and how do they arise in metabolism? Explain why they accumulate under conditions of carbohydrate starvation or in diabetes.


What gland produces cortisol? What factors regulate cortisol production? What functions are controlled by cortisol?

Pure Preparation of the Enzyme that Catalyzes Palmitate Synthesis

The following experiments are carried out using a pure preparation of the enzyme that catalyzes palmitate synthesis from acetyl CoA and malonyl CoA in the presence of all the cofactors required for reaction. a) If the acetyl CoA is labeled at the methyl carbon with tritium, and malonyl CoA is unlabeled, how many tritium atom

Fatty Acids: Reactions, Mechanisms and Enzymes

Purified fatty acid synthetase from liver cytoplasm normally catalyzes the sythesis of palmitate(C16) from acetyl CoA, malonyl CoA, and NADPH. The enzyme also will function, although at considerably reduced rates, if the acetyl CoA is replaced by (1) propionyl CoA or (2) butyryl CoA. a) What do you predict will be the major p

Glucose as Intravenous Food Source

Glucose is frequently administered intravenonusly to patients as a food source. A new resident at the hospital suggests administering glucose-6-phosphate instead. Glucose-6-phosphate requires ATP and you consider the possibility that administering glucose-6-phosphate might save the patient energy. Should you use the resident

Reaction, Control Point and Citric Acid Cycle

The dG' for the fumerase reaction is -3.4kJ/mol, but Δ G' is near 0. What is the ratio of fumarate to malate under cellular conditions at 37.0C? Is this reaction likely to be a control point in the citric acid cycle?

Scientific Experiment Report

Can you answer this problem for me in a good detailed form? This is the experiment I have to experiment estimate some results and do a conclusion and discussion of the way in which the method may of reflected in my results can you: Predict the results Explain results you have predicted Give sources of error for the method

Metabolism During Heart Attack

During a heart attack, blood flowing to the heart muscle is interrupted by blockage of a coronary artery. How would you expect the metabolism in the heart to change? A. oxidative phosphorylation would slow down in the mitochondria B. the rate of production of lactic acid would be stimulated C. the use of glucose by the

Lactic Acid Production

A new drug was found to decrease Hepatitis B virus. The drug is an analogue of one of the nucleic acid bases of DNA and probably works by being incorporated into the virus and disrupting viral genes during viral DNA replication. However, patients in a clinical trial of the drug began to experience drastic overproduction of lacti