Chapter 6 - Cells Metabolism Flashcards
What is Metabolism?
Metabolism isn’t just one thing, it describes every single biochemical reaction that occurs in your body. It converts food you eat into energy and materials needed for your body to properly function. There are two main processes that make up metabolism ;
- anabolism ; construct things and consume energy.
- catabolism ; break down big molecules and release energy.
What are organic compounds?
Organic compounds have large molecules that always contain the element carbon. Carbohydrates, amino acids, proteins and lipids are all organic compounds.
What are Enzymes?
Enzymes are proteins that allow chemical reactions to take place at normal body temperature. Without Enzymes, these reactions would be too slow to be any use to the body. Enzymes decrease the need for activation energy and allow chemical reactions to proceed at a rate in which suits the body’s requirements.
Explain the relationship between Enzymes and substrates.
Enzymes are very specific and will only combine with one particular type of substrate. This is often shown in a lock and key model in which a substrate and enzyme combine in an active site to form an enzyme - substrate complex.
What are the 7 factors that affect enzyme activity?
- the higher the concentration of enzyme, the faster the rate of a chemical reaction.
- the higher the concentration of substrate, the faster the rate of a chemical reaction.
- the products of the reaction are continually removed so that new substrates can come through.
- temperature influences enzyme activity. The optimum temperature for enzyme activity is between 30-40°C.
- pH influences enzyme activity. Each enzyme has an optimum pH that they work best in.
- the presence of co-factors. Co-factors and co-Enzymes change the shape of the active site so that the enzyme can combine with a substrate.
- enzyme inhibitors can slow or even stop enzyme activity. It regulates the amount of product produced and at what rate they are produced.
What is cellular respiration?
Cellular respiration is one of the most important metabolic process in the body. It is the process in which organic molecules such as food, are broken down in cells to release energy for the cell’s activities. The main food material utilised is glucose.
What is the equation for respiration?
C6 H12 O6 + 6O2 = 6CO2 + 6H20 + energy
aka
Glucose + oxygen = carbon dioxide + water + energy.
What happens to the energy from the cellular respiration?
In the complete breakdown of glucose to carbon dioxide and water, about 60% of the energy is released as heat that is used to keep body temperature constant. The remaining energy is used to form the compound ATP (adenosine triphosphate). ATP is formed when an inorganic phosphate group joins to the molecule of ADP (adenosine diphosphate) by a high- energy chemical bond that can easily be broken.
What happens when ATP is converted back to ADP?
Removal of the third phosphate group in ATP releases energy that can be used by the cell. The ADP that is then formed can be reused to store more energy and become ATP once again. It is a continuous cycle.
What is Anaerobic respiration?
Anaerobic respiration does not require oxygen and is therefore carried out in the cytosol of the cell. It involves glycolysis, which is the break down of glucose to pyruvic acid. Anaerobic respiration breaks down one glucose molecule into two pyruvic acid molecules - which then becomes lactic acid if oxygen is not present. Anaerobic respiration produces two molecules of ATP and two pyruvic molecules.
What is Aerobic respiration?
Complete breakdown of glucose to carbon dioxide requires oxygen, which means aerobic respiration is carried out in the mitochondria. The two pyruvic acid molecules enter a mitochondrion where enzymes are available to undergo two or more series of reactions to occur ; Krebs cycle or electron transport system. Aerobic respiration has the potential to from up to 38 molecules of ATP.
What is Synthesis?
Synthesis is the combining of small molecules to make larger molecules. For example, proteins are synthesised from amino acids. Synthesis requires both energy and matter.
What are some of the uses of Energy released through cellular respiration?
- building complex molecules
- cell division and growth
- maintaining cell organisation
- active transport
And of course - heat energy
What are the 6 groups of nutrients?
Water, carbohydrates, lipids, proteins, minerals and vitamins
