Alterations to Metabolism and Energy Production Flashcards
Carbohydrate, Fat & Protein Metabolism
Protein –> amino acids - Proteases
Carbohydrates –> Glucose - Amylase
Fats –> Fatty acids & Glycerol - Lipase
Three main pathways of metabolism the human body
Catabolism (breaking down), Anabolism (Building up) and Waste Disposal (removal)
Chemical Equation for energy production
ATP + H2O —–> ADP + Pi + free energy
Source of energy that fuels cellular functions
ATP
Which vitamins are essential for mitochondrial function and aerobic
respiration?
Vitamin B1, B2, B3. B6, B12, folic acid
Would the availability of oxygen impact on the amount of energy
that is produced by the cell?
Without oxgyen, the process will only produce 2 ATP molecules, whilst with oxygen, it produces 38 ATP molecules
Oxygen improves the efficiency of ATP production
Electron transport chain - needs the oxygen thus anaerobic respiration only produces 2 ATP molecules
Explain why hypoxia leads to multiple system failure
Oxygen is needed for the electron transport chain (oxidative phosphorylation)
- No O2 means no regeneration of NAD and FAD which leads to no ATP output which causes cellular failure and organ failure
What is glycogen synthesis and where does it take place?
Where glucose molecules are added to chains of glycogen for storage, it takes place in many tissues, but it important in the liver and muscle
What is Gluconeogenesis?
Process by which glucose is made from the biosynthesis of simpler non-carbohydrate precursors such as pyruvate
examples of non-carbohydrate substrates include:
- lactic acid
- amino acids
- glycerol
Jennifer is currently on the Atkins diet and is not consuming any
carbohydrates. Would she still be able to make energy?
Body starts to burn fat, causing build up in ketones in the blood, leading to ketosis
What happens when N2 is kept in the body
- Excess nitrogen is excreted from the body.
Nitrogenous wastes tend to form toxic ammonia, which raises the pH of body fluids. The formation of ammonia itself requires energy in the form of ATP and large quantities of water to dilute it out of a biological system.
These wastes are converted to less harmful urea by the liver
It can lead to cerebral oedema, confusion, delirium due to its effects on brain tissue
What factors influence enzyme function?
pH
- enzymes function within a narrow pH, changes lead to denaturing
Temperature
- Work best at an optimal temperature, changes lead to denaturing - this is due to the breakdown of intra-intermolecular forces due to increased kinetic energy
Initial concentration of substrate and enzyme
Why would a mutation in the DNA of an enzyme result in it becoming ineffective?
when gene mutation occurs, an amino acid may change in the sequence
- Protein folding is highly dependent on amino acid sequence and composition, alterations will change final structure and reaction sites thus enzyme may lose its functionality
Two common IEM are phenylketonuria and cystinuria. Describe
these disorders including their incidence rates
Phenylketonuria (PKU) is a rare inherited disorder that causes an amino acid called phenylalanine to build up in the body. PKU is caused by a defect in the gene that helps create the enzyme needed to break down phenylalanine, can cause intellectual disabilities
Cystinuria is an inherited disease that causes stones made of the amino acid cystine to form in the kidneys, bladder, and ureters
Cystinuria is caused by too much cystine in the urine. Normally, most cystine dissolves and returns to the bloodstream after entering the kidneys. People with cystinuria have a genetic defect that interferes with this process. As a result, cystine builds up in the urine and forms crystals or stones
Name disease that can cause malabsorptionand maldigestion
Crohn’s disease, Anorexia nervosa, Coeliac disease
- if patient is not absorbing right nutrients, the patient may not be able to produce all of the substrates and products required for metabolism
What nursing methods can maintain nutrient levels in a patient who is poorly absorbing nutrients?
Enteral hyperalimentation
- administration of elemental nutrients via a catheter placed within the intestinal tract
Total parenteral nutrition
- feeding a person intravenously, bypassing the usual process of eating and digestion
Nasogastric tubes
What are the common diseases in Australia?
Colorectal - 10.7% Pancreatic - 5.2% Oesophageal - 3.0% Gastric - 2.8% Hepatic - 2.4%
Pathophysiology of Colorectal Cancer
Related to colorectal polyps- which is why they are removed in colonoscopy
- Carinoma starts in the glands of the mucosal lining
- genetics and a diet high in fat, low in fibre and low in calcium may promote colorectal cancer development
- bleeding may be evident, pain may be present
- faeces may decrease in size or an obsruction may develop
What is irritable bowel syndrome?
An intestinal disorder causing pain in the stomach, wind, diarrhoea and constipation.
Structural changes of the bowel does not occur rather the afflicted person experiences abdominal pain and discomfort and altered bowel habits
- Difficult to define as structural changes don’t occur
Pathophysiology of Crohn’s disease
Inflammatory disorder that affects the small and large intestine
- Neutrophils and macrophages promote inflammatory reaction
- Genetic predisposition and alterations in normal bowel flora is suspected
Pathophysiology of Diverticular Disease
Condition that causes small bulges (diverticula) or sacs to form in the wall of the large intestine (colon)
Diverticula are sac like out pouchings or hernitations that occur in the mucousae and protrude through the muscle layers of the large intestine
- Regular consumption of a low fibre diet reduces faecal bulk - thus reducing the diameter of the colon - diverticula can rupture under increased pressure
Pathophysiology of Appendicits
Inflammation of the Vernifor Appendix
- Exact mechanism is controversial
- obstruction of the lumen with faeces, tumours etc.
- consequent bacterial infection leading to oedema, gangrene and perforation
Describe Peptic Ulcer Disease
Peptic ulcer is a break (ulcerations) in the wall of the mucosal lining of the stomach or duodenum
- Can cause significant bleeding
Risk factors include
- smoking
- increased age
- habitual use of NSAIDS
- Alcohol
- Physiological Stress
What nutritional disorders occur as the result of alteration in digestive physiology?
Lactose intolerance
- Due to deficiency in the enzyme lactase which breaks down lactose into its smaller components glucose and galactose
Coeliac disease
- loss of the mature intestinal villi caused by a hypersensitively to gluten. This results in malabsorption of nutrients
