Results for "AMMONIA"

Unit 10 – Drugs for Central Nervous System (CNS) Problems (Comprehensive Study Guide – Nursing Pharmacology) ⸻ 🧩 Central Nervous System (CNS) Overview • CNS = Brain + Spinal Cord • Controls body movement, behavior, and cognitive function. • Neurotransmitters are chemicals that transmit signals between neurons. • Excitatory: Acetylcholine (ACh), epinephrine, norepinephrine • Inhibitory: Dopamine, serotonin, gamma-aminobutyric acid (GABA) ⚖️ Balance of dopamine and acetylcholine is critical for smooth movement. An imbalance leads to disorders like Parkinson’s Disease. ⸻ 🧍‍♂️ Parkinson’s Disease (PD) Cause • Progressive CNS disorder due to low dopamine production in the substantia nigra. • Too little dopamine → too much acetylcholine, causing impaired motor control. Key Symptoms Motor: • Tremors (“pill-rolling”) • Bradykinesia (slow movements) • Muscle rigidity, stiffness • Stooped posture, shuffling gait • Difficulty rising, “freezing in place” • Masklike facial expression Nonmotor: • Constipation, urinary frequency • Depression, anxiety, hallucinations • Sleep issues, fatigue • Memory problems ⸻ Drug Classes for PD Goal: Restore balance between dopamine and acetylcholine. 1️⃣ Dopamine Agonists Action: Mimic or increase dopamine. Improve movement, coordination, and muscle control. Examples: • carbidopa/levodopa (Sinemet, Rytary) • pramipexole (Mirapex ER) • ropinirole (Requip) • rotigotine (Neupro patch) Nursing Implications & Teaching: • Give 30–60 min before meals (empty stomach). • Avoid protein-rich foods (reduces absorption). • Monitor for orthostatic hypotension — rise slowly. • Don’t crush extended-release tablets. • Neupro patch: rotate sites, don’t reuse within 14 days. • Avoid vitamin B6 unless taken with carbidopa. • Takes 2–3 weeks for full effect. Side Effects: • Hypotension, headache, nausea, insomnia • Dyskinesia (abnormal movements) • “On/off effect” – medication wears off quickly • Long-term use → hallucinations, impulse control problems Adverse Effects: • Neuroleptic malignant syndrome: fever, rigidity, confusion • Psychosis, severe hypotension ⸻ 2️⃣ COMT Inhibitors Action: Block COMT enzyme → prolong dopamine activity. Examples: • entacapone (Comtan) • tolcapone (Tasmar) Nursing Implications: • Always give with carbidopa/levodopa. • Monitor liver function (q6 months) – risk of liver failure (especially tolcapone). • Harmless side effect: brown-orange urine. • Rise slowly to prevent hypotension. ⸻ 3️⃣ MAO-B Inhibitors Action: Inhibit MAO-B enzyme → prevents dopamine breakdown. Examples: • selegiline (Eldepryl) • rasagiline (Azilect) • safinamide (Xadago) Teaching: • Avoid foods high in tyramine → hypertensive crisis risk. (Aged cheese, wine, beer, cured meats, soy sauce, yogurt, avocados, bananas) • Monitor BP closely. • Avoid OTC decongestants or stimulants. • Can cause insomnia, dizziness, dry mouth, or constipation. ⸻ 🧠 Alzheimer’s Disease (AD) Cause • Progressive neurodegenerative disorder leading to memory loss, confusion, and poor judgment. • Loss of acetylcholine (ACh) and buildup of amyloid plaques and neurofibrillary tangles in the brain. Symptoms • Early: forgetfulness, confusion, mood changes. • Late: loss of reasoning, personality changes, inability to perform ADLs. ⸻ Drug Classes for AD 1️⃣ Cholinesterase Inhibitors Action: Block enzyme acetylcholinesterase (AChE) → increases ACh → improves memory and function. Examples: • donepezil (Aricept) • rivastigmine (Exelon) • galantamine (Razadyne) Side Effects: • Nausea, vomiting, diarrhea • Loss of appetite, GI discomfort • Drowsiness, headache, insomnia • Muscle cramps, bradycardia Adverse Effects: • Dysrhythmias, GI bleeding, hallucinations • Overstimulation of parasympathetic system (too much ACh) Nursing Implications: • Give at bedtime to reduce nausea. • Monitor weight, HR, and mental changes. • Report black/tarry stools or vomiting blood. • Avoid OTC anticholinergics (they reduce effectiveness). ⸻ 2️⃣ NMDA Blockers Action: Block NMDA receptor → decreases glutamate activity → prevents neuron death. Example: • memantine (Namenda) Used in: Moderate to severe AD (often combined with donepezil). ⸻ ⚡ Epilepsy / Seizure Drugs (AEDs) Purpose Reduce excessive electrical activity in the brain and prevent seizures. Common AEDs: • phenytoin (Dilantin) – prevents neuron excitation • topiramate (Topamax) – broad-spectrum seizure control Topiramate Key Points: • Side effects: dizziness, drowsiness, taste changes, paresthesias (“pins and needles”) • Adverse: metabolic acidosis, ↑ ammonia → confusion, lethargy, vomiting • Monitor: serum bicarbonate & ammonia levels • Teaching: stay hydrated, report mental status changes, don’t crush tablets • Contraindicated in pregnancy (teratogenic) ⸻ 💥 Multiple Sclerosis (MS) Pathophysiology • Autoimmune disease where the immune system attacks myelin (fatty sheath around neurons). • Leads to nerve signal disruption → muscle weakness and loss of coordination. • Common type: Relapsing-Remitting MS (RRMS) – periods of flare-ups and remission. Common Symptoms • Fatigue, weakness, difficulty walking • Double vision or blurred vision • Tingling or numbness • Bladder/bowel dysfunction • Depression, poor concentration ⸻ Drug Therapy for MS 1️⃣ Biological Response Modifiers (BRMs) Action: Modify immune system activity and slow disease progression. Examples: • beta-interferons (Avonex, Betaseron, Rebif, Extavia, Plegridy) • glatiramer (Copaxone) • fingolimod (Gilenya) • teriflunomide (Aubagio) Side Effects: • Flu-like symptoms, headache, fatigue • Elevated liver enzymes, slow HR • Thinning scalp hair Nursing Teaching: • Rotate injection sites. • Monitor liver enzymes, CBC, and heart rate. • Avoid live vaccines. ⸻ 2️⃣ Monoclonal Antibodies Action: Destroy lymphocytes that attack myelin. Examples: • alemtuzumab (Lemtrada) • natalizumab (Tysabri) • ocrelizumab (Ocrevus) Side Effects: • Increased risk of infection • Headache, rash, fatigue • GI upset Nursing Teaching: • Given IV every few months to yearly. • Monitor for infusion reactions and infection signs. ⸻ 3️⃣ Neurologic Drugs Examples: • dimethyl fumarate (Tecfidera) – reduces CNS inflammation • dalfampridine (Ampyra) – improves walking by increasing nerve conduction Teaching: • Take daily; don’t crush tablets. • Watch for GI symptoms and dizziness. ⸻ 💪 Amyotrophic Lateral Sclerosis (ALS) Description • Progressive, fatal disorder destroying motor neurons → paralysis. • Death usually occurs within 3–5 years of diagnosis. Drug Therapy Glutamate Antagonists Example: • riluzole (Rilutek, Tiglutik) Action: Inhibits glutamate release → slows neuron damage → prolongs life by months. Side Effects: • Weakness, nausea, dizziness • Liver toxicity (↑ liver enzymes) • Neutropenia, anemia Nursing Implications: • Monitor liver enzymes before and during therapy. • Report jaundice or dark urine. • Take on an empty stomach (1 hr before or 2 hrs after meals). • Avoid alcohol. • Don’t breastfeed while on this med. ⸻ ⚙️ Myasthenia Gravis (MG) Description • Autoimmune disease destroying acetylcholine receptors at neuromuscular junction. • Causes muscle weakness and fatigue, especially in eyes, mouth, throat. Symptoms • Ptosis (drooping eyelids) • Difficulty chewing/swallowing • Weakness in arms, legs, or respiratory muscles • Worsens with activity, improves with rest ⸻ Drug Therapy Acetylcholinesterase Inhibitors Action: Prevent breakdown of acetylcholine → improves nerve–muscle communication. Example: • pyridostigmine (Mestinon) Dosage: Usually every 4–6 hours, depending on patient response. Side Effects: • Nausea, vomiting, abdominal cramps, diarrhea • Increased salivation, sweating • Bradycardia, hypotension Adverse: • Cholinergic crisis (too much medication): → extreme weakness, bradycardia, bronchospasm, respiratory arrest. Nursing Implications: • Use with caution in asthma, COPD, bradycardia. • Give doses at same time each day to maintain muscle strength. • Monitor for myasthenic vs. cholinergic crisis. • Give meds 30–45 min before meals to prevent aspiration. Patient Teaching: • Take missed dose ASAP (but skip if close to next dose). • Don’t double dose. • Avoid alcohol and sedatives. • Report muscle weakness or breathing difficulty. • Keep atropine available (antidote for cholinergic crisis)

Ammonia

Lecture 7 & 8: N Fixation and Ammonia Assimilation

Haber Process - Industrial Process of Ammonia

Lab preparation of ammonia

Creatinine, Uric Acid, BUN, and Ammonia

ammonia

Chương II-Ammonia và muối Ammonium

ASSESSMENT OF THE LIVER Anatomic and Physiologic Overview The liver, the largest gland of the body and a major organ, can be considered a chemical factory that manufactures, stores, alters, and excretes a large number of substances involved in metabolism (Hammer & McPhee, 2019; Sanyal, Boyer, Terrault, et al., 2018). The location of the liver is essential because it receives nutrient-rich blood directly from the gastrointestinal (GI) tract and then either stores or transforms these nutrients into chemicals that are used elsewhere in the body for metabolic needs. The liver is especially important in the regulation of glucose and protein metabolism. The liver manufactures and secretes bile, which has a major role in the digestion and absorption of fats in the GI tract. The liver removes waste products from the bloodstream and secretes them into the bile. The bile produced by the liver is stored temporarily in the gallbladder until it is needed for digestion, at which time the gallbladder empties and bile enters the intestine (see Fig. 43-1). Anatomy of the Liver The liver is a large, highly vascular organ located behind the ribs in the upper right portion of the abdominal cavity. It weighs between 1200 and 1500 g in the average adult and is divided into four lobes. A thin layer of connective tissue surrounds each lobe, extending into the lobe itself and dividing the liver mass into small, functional units called lobules (Barrett, Barman, Brooks, et al., 2019; Hammer & McPhee, 2019). The circulation of the blood into and out of the liver is of major importance to liver function. The blood that perfuses the liver comes from two sources. Approximately 80% of the blood supply comes from the portal vein, which drains the GI tract and is rich in nutrients but lacks oxygen. The remainder of the blood supply enters by way of the hepatic artery and is rich in oxygen. Terminal branches of these two blood vessels join to form common capillary beds, which constitute the sinusoids of the liver (see Fig. 43-2). Thus, a mixture of venous and arterial blood bathes the hepatocytes (liver cells). The sinusoids empty into venules that occupy the center of each liver lobule and are called the central veins. The central veins join to form the hepatic vein, which constitutes the venous drainage from the liver and empties into the inferior vena cava, close to the diaphragm (Barrett et al., 2019; Hammer & McPhee, 2019; Sanyal et al., 2018). In addition to hepatocytes, phagocytic cells belonging to the reticuloendothelial system are present in the liver. Other organs that contain reticuloendothelial cells are the spleen, bone marrow, lymph nodes, and lungs. In the liver, these cells are called Kupffer cells (Barrett et al., 2019; Hammer & McPhee, 2019). As the most common phagocyte in the human body, their main function is to engulf particulate matter (e.g., bacteria) that enters the liver through the portal blood. The smallest bile ducts, called canaliculi, are located between the lobules of the liver. The canaliculi receive secretions from the hepatocytes and carry them to larger bile ducts, which eventually form the hepatic duct. The hepatic duct from the liver and the cystic duct from the gallbladder join to form the common bile duct, which empties into the small intestine. The sphincter of Oddi, located at the junction where the common bile duct enters the duodenum, controls the flow of bile into the intestine. Figure 43-1 • The liver and biliary system, including the gallbladder and bile ducts. Reprinted with permission from Norris, T. L. (2019). Porth’s pathophysiology: Concepts of altered health states (10th ed., Fig. 38.1). Philadelphia, PA: Wolters Kluwer. Figure 43-2 • A section of liver lobule showing the location of hepatic veins, hepatic cells, liver sinusoids, and branches of the portal vein and hepatic artery. Functions of the Liver Glucose Metabolism The liver plays a major role in the metabolism of glucose and the regulation of blood glucose concentration. After a meal, glucose is taken up from the portal venous blood by the liver and converted into glycogen, which is stored in the hepatocytes. Subsequently, the glycogen is converted back to glucose through a process called glycogenolysis and is released as needed into the bloodstream to maintain normal levels of blood glucose. However, this process provides a limited amount of glucose. Additional glucose can be synthesized by the liver through a process called gluconeogenesis. For this process, the liver uses amino acids from protein breakdown or lactate produced by exercising muscles. This process occurs in response to hypoglycemia (Barrett et al., 2019; Hammer & McPhee, 2019). Ammonia Conversion The use of amino acids from protein for gluconeogenesis results in the formation of ammonia as a by-product. The liver converts this metabolically generated ammonia into urea. Ammonia produced by bacteria in the intestines is also removed from portal blood for urea synthesis. In this way, the liver converts ammonia, a potential toxin, into urea, a compound that is excreted in the urine (Barrett et al., 2019; Hammer & McPhee, 2019). Protein Metabolism The liver also plays an important role in protein metabolism. It synthesizes almost all of the plasma proteins (except gamma-globulin), including albumin, alpha-globulins and beta-globulins, blood clotting factors, specific transport proteins, and most of the plasma lipoproteins. Vitamin K is required by the liver for synthesis of prothrombin and some of the other clotting factors. Amino acids are used by the liver for protein synthesis (Barrett et al., 2019; Hammer & McPhee, 2019). Fat Metabolism The liver is also active in fat metabolism. Fatty acids can be broken down for the production of energy and ketone bodies (acetoacetic acid, beta-hydroxybutyric acid, and acetone). Ketone bodies are small compounds that can enter the bloodstream and provide a source of energy for muscles and other tissues. Breakdown of fatty acids into ketone bodies occurs primarily when the availability of glucose for metabolism is limited, as in starvation or in uncontrolled diabetes. Fatty acids and their metabolic products are also used for the synthesis of cholesterol, lecithin, lipoproteins, and other complex lipids (Hammer & McPhee, 2019; Sanyal et al., 2018). Vitamin and Iron Storage Vitamins A, B, and D and several of the B-complex vitamins are stored in large amounts in the liver. Certain substances, such as iron and copper, are also stored in the liver. Bile Formation Bile is continuously formed by the hepatocytes and collected in the canaliculi and bile ducts. It is composed mainly of water and electrolytes such as sodium, potassium, calcium, chloride, and bicarbonate, and it also contains significant amounts of lecithin, fatty acids, cholesterol, bilirubin, and bile salts. Bile is collected and stored in the gallbladder and is emptied into the intestine as needed for digestion. The functions of bile are excretory, as in the excretion of bilirubin; bile also serves as an aid to digestion through the emulsification of fats by bile salts. Bile salts are synthesized by the hepatocytes from cholesterol. After conjugation or binding with amino acids (taurine and glycine), bile salts are excreted into the bile. The bile salts, together with cholesterol and lecithin, are required for emulsification of fats in the intestine, which is necessary for efficient digestion and absorption. Bile salts are then reabsorbed, primarily in the distal ileum, into portal blood for return to the liver and are again excreted into the bile. This pathway from hepatocytes to bile to intestine and back to the hepatocytes is called the enterohepatic circulation. Because of the enterohepatic circulation, only a small fraction of the bile salts that enter the intestine are excreted in the feces. This decreases the need for active synthesis of bile salts by the liver cells (Hammer & McPhee, 2019). Bilirubin Excretion Bilirubin is a pigment derived from the breakdown of hemoglobin by cells of the reticuloendothelial system, including the Kupffer cells of the liver. Hepatocytes remove bilirubin from the blood and chemically modify it through conjugation to glucuronic acid, which makes the bilirubin more soluble in aqueous solutions. The conjugated bilirubin is secreted by the hepatocytes into the adjacent bile canaliculi and is eventually carried in the bile into the duodenum. p. 1366 p. 1367 In the small intestine, bilirubin is converted into urobilinogen, which is partially excreted in the feces and partially absorbed through the intestinal mucosa into the portal blood. Much of this reabsorbed urobilinogen is removed by the hepatocytes and secreted into the bile once again (enterohepatic circulation). Some of the urobilinogen enters the systemic circulation and is excreted by the kidneys in the urine. Elimination of bilirubin in the bile represents the major route of its excretion. Drug Metabolism The liver metabolizes many medications, such as barbiturates, opioids, sedatives, anesthetics, and amphetamines (Goldman & Schafer, 2019; Hammer & McPhee, 2019; Sanyal et al., 2018). Metabolism generally results in drug inactivation, although activation may also occur. One of the important pathways for medication metabolism involves conjugation (binding) of the medication with a variety of compounds, such as glucuronic acid or acetic acid, to form more soluble substances. These substances may be excreted in the feces or urine, similar to bilirubin excretion. Bioavailability is the fraction of the given medication that actually reaches the systemic circulation. The bioavailability of an oral medication (absorbed from the GI tract) can be decreased if the medication is metabolized to a great extent by the liver before it reaches the systemic circulation; this is known as first-pass effect. Some medications have such a large first-pass effect that their use is essentially limited to the parenteral route, or oral doses must be substantially larger than parenteral doses to achieve the same effect. Gerontologic Considerations Chart 43-1 summarizes age-related changes in the liver. In the older adult, the most common change in the liver is a decrease in size and weight, accompanied by a decrease in total hepatic blood flow. However, in general, these decreases are proportional to the decreases in body size and weight seen in normal aging. Results of liver function tests do not normally change with age; abnormal results in older patients indicate abnormal liver function and are not a result of the aging process itself. Chart 43-1 Age-Related Changes of the Hepatobiliary System •Atypical clinical presentation of biliary disease •Decreases in the following: •Clearance of hepatitis B surface antigen •Drug metabolism and clearance capabilities •Intestinal and portal vein blood flow •Gallbladder contraction after a meal •Rate of replacement and or repair of liver cells after injury •Size and weight of the liver, particularly in women •Increased prevalence of gallstones due to the increase in cholesterol secretion in bile •More rapid progression of hepatitis C infection and lower response rate to therapy •More severe complications of biliary tract disease Adapted from Townsend, C. M., Beauchamp, R. D., Evers, B. M., et al. (2016). Sabiston’s textbook of surgery: The biological basis of modern surgical practice. Philadelphia, PA: Elsevier. Metabolism of medications by the liver decreases in the older adult, but such changes are usually accompanied by changes in intestinal absorption, renal excretion, and altered body distribution of some medications secondary to changes in fat deposition. These alterations necessitate careful medication administration and monitoring; if appropriate, reduced dosages may be needed to prevent medication toxicity

Chemie Test: Stickstoff (N₂) & Ammoniak (NH₃)

Multiple choice, continued (3 points each). Name:__________________ Please circle your answer. There is only one correct answer to each question. 36. How many different resonance structures can be drawn for the molecule SO3 without having to violate the octet rule on the sulfur atom? A) 5 B) 4 C) 3 D) 2 37. The central atom in _______ does not violate the octet rule. A) CF4 B) KrF2 C) SF4 D) XeF4 38. For a given arrangement of ions, the lattice energy increases as ionic radius _________ and as ionic charge __________. A) increases, increases B) decreases, decreases C) increases, decreases D) decreases, increases 39. Of the molecules below, only ________ is nonpolar. A) HCl B) NH3 C) SO2 D) CO2 40. Using the table of bond dissociation energies, ∆H for the reaction 2HCl (g) + F2 (g) à 2HF (g) + Cl2 (g) is __________ kJ. Bond D (kJ/mol) H – Cl 431 F – F 155 H – F 567 Cl – Cl 242 A) –359 B) -223 C) 359 D) 223 41. Considering its Lewis structure, the electron-domain geometry of oxygen in OF2 is ___________. A) trigonal planar B) trigonal bipyramidal C) octahedral D) tetrahedral 42. The electron-domain geometry and the molecular geometry of ammonia, NH3, are __________ and __________, respectively. A) tetrahedral, trigonal pyramidal B) tetrahedral, trigonal planar C) bent, bent D) trigonal planar, bent

Part II. Multiple choice, continued (3 points each). Name:__________________ Please circle your answer. There is only one correct answer to each question. 14. Which of the following compounds would you expect to be ionic? A) SF6 B) H2O C) H2O2 D) CaO 15. Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N2 (g) + 3H2 (g) à 2NH3 (g) A 9.3-g sample of H2 requires ____________ g of N2 for a complete reaction. A) 43 B) 1.3 x 102 C) 3.9 x 102 D) 4.6 16. What is the frequency of light (s-1) that has a wavelength of 1.23 x 10-6 cm? A) 3.69 B) 2.44 x 1016 C) 4.10 x 10-17 D) 9.62 x 1012 17. Which sketch represents an orbital with the quantum numbers n = 3, l = 1, ml = 0? A) B) C) D) 18. What color of visible light has the longest wavelength? A) blue B) violet C) red D) yellow 19. According to the Heisenberg Uncertainty Principle, it is impossible to know precisely both the position and the __________ of an electron. A) mass B) color C) momentum D) shape 20. The wavelength of a photon that has an energy of 5.25 x 10-19 J is ___________ m. A) 3.79 x 10-7 B) 2.64 x 106 C) 2.38 x 1023 D) 3.79 x 107 21. There are ___________ orbitals in the second shell. A) 2 B) 4 C) 9 D) 18

Technische Ammoniaksynthese

To show the reaction between ethanol and ammoniacal silver nitrate /Tollen's reagent (silver mirror test)

CC-Lab Ammonia & Uric Acid

Reaction of ethanal with ammoniacal silver nitrate

Transport of Ammonia - Lecture Review

System Interactions in Animals Tools Finish System Interactions in Animals The human body is made of many different organ systems. Each system performs unique functions for the body, but the systems also interact with each other to perform more complex functions. Major Organ Systems Body Systems In humans, cells, tissues, and organs group together to form organ systems. These systems each perform different functions for the human body. The major organ systems and their functions in humans include: The Nervous System — The nervous systems consists of two parts. The central nervous system consists of the brain and spinal cord, while the peripheral nervous system consists of nerves that connect the central nervous system to other parts of the body. The brain plays an important role in interpreting the information picked up by the sensory system. It helps in producing a precise response to the stimuli. It also controls bodily functions such as movements, thoughts, speech, and memory. The brain also controls many processes related to homeostasis in the body. The spinal cord connects to the brain through the brainstem. From the brainstem, the spinal cord extends to all the major nerves in the body. The spinal cord is the origin of spinal nerves that branch out to various body parts. These nerves help in receiving and transmitting signals from various body parts. The spinal cord helps in reflex actions of the body The smallest unit of the nervous system is the nerve cell, or neuron. Neurons communicate with each other and with other cells by producing and releasing electrochemical signals known as nerve impulses. Neurons consist of the cell body, the dendrites, and the axon. The cell body consists of a nucleus and cytoplasm. Dendrites are specialized branch-like structures that help in conducting impulses to and from the various body parts. Axons are long, slender extensions of the neuron. Each neuron possesses just a single axon. Its function is to carry the impulses away from the cell body to other neurons. The Circulatory System — The circulatory (or cardiovascular) system is composed of the heart, arteries, veins, and capillaries. The circulatory system is responsible for transporting blood to and from the lungs so that gas exchange can take place. As the circulatory system pumps blood throughout the body, dissolved nutrients and wastes are also delivered to their destinations. The heart is a muscular organ roughly the size of an adult human's closed fist. It is present behind the breastbone, slightly to the left. It consists of four chambers: right atrium, left atrium, right ventricle, and left ventricle. The heart receives deoxygenated blood from the body and pumps this blood to the lugs, where it is oxygenated. The oxygen-rich blood reenters the heart and is then pumped back through the body. The circulatory system is responsible for transporting blood to and from the lungs so that gas exchange can take place. As the circulatory system pumps blood throughout the body, dissolved nutrients and wastes are also delivered to their destinations. Blood circulation takes place through blood vessels. Blood vessels are tubular structures that form a network within the body and transport blood to each tissue. There are three major types of blood vessels: veins, arteries, and capillaries. Veins carry deoxygenated blood from the body to the heart, except for pulmonary veins, which carry oxygenated blood from the lungs to the heart. Arteries carry oxygenated blood from the heart to different organs, except for the pulmonary artery, which carries deoxygenated blood from the heart to the lungs. The arteries branch out to form capillaries. These capillaries are thin-walled vessels through which nutrients and wastes are exchanged with cells. The Respiratory System — The main structures of the respiratory system are the trachea (windpipe), the lungs, and the diaphragm. When the diaphragm contracts, it creates a vacuum in the lungs that causes them to fill with air. During this inhalation, oxygen diffuses into the circulatory system while carbon dioxide diffuses out into the air that will be exhaled. The trachea branches out into two primary bronchi. Each bronchus is further divided into numerous secondary bronchi. These secondary bronchi further branch into tertiary bronchi. Finally, each tertiary bronchus branches into numerous bronchioles. Each bronchiole terminates into a tiny, sac-like structure known as an alveolus. The walls of each alveolus are thin and contain numerous blood capillaries. The process of gaseous exchange occurs in these alveoli. The diaphragm is a dome-shaped muscle situated at the lower end of the rib cage. It separates the abdominal cavity from the chest cavity. During inhalation, the diaphragm contracts, and the chest cavity enlarges, creating a vacuum that allows air to be drawn in. This causes the alveoli in the lungs to expand with air. During this process, oxygen diffuses into the circulatory system while carbon dioxide diffuses out into the air that will be exhaled. On the other hand, expansion of the diaphragm causes exhalation of air containing carbon dioxide. The Digestive System — The digestive system consists of the mouth, stomach, small intestine, large intestine, and anus. It is responsible for taking in food, digesting it to extract energy and nutrients that cells can use to function, and expelling the remaining waste material. Mechanical and chemical digestion takes place in the mouth and stomach, while absorption of nutrients and water takes place in the intestines. The digestive system begins at the mouth, where food is taken in, and ends at the anus, where waste is expelled. The food taken into the mouth breaks into pieces by the grinding action of the teeth. Carbohydrate digestion starts in the mouth with the breakdown of carbohydrates into simple sugars with the help of salivary enzymes. The chewed food, known as a bolus, enters the stomach through the esophagus. The bolus mixes with acids and enzymes released by the stomach. Protein digestion starts in the stomach as proteins are broken down into peptides. This partially digested food is known as chyme. Chyme enters the small intestine and mixes with bile, a substance secreted by the liver, along with enzymes secreted by the pancreas. The digestion of fats starts in the small intestine as bile and pancreatic enzymes break down fats into fatty acids. The surface of the small intestine consists of hair-like projections known as villi. These villi help in absorbing nutrients from the digested food. The digested food enters the large intestine, or colon, where water and salts are reabsorbed. Any undigested food is expelled out of the body as waste. The Skeletal System — The skeletal system is made up of over 200 bones. It protects the body's internal organs, provides support for the body and gives it shape, and works with the muscular system to move the body. In addition, bones can store calcium and produce red and white blood cells. The Muscular System — The muscular system includes more than 650 tough, elastic pieces of tissue. The primary function of any muscle tissue is movement. This includes the movement of blood through the arteries, the movement of food through the digestive tract, and the movement of arms and legs through space. Skeletal muscles relax and contract to move the bones of the skeletal system. The Excretory System — The excretory system removes excess water, dangerous substances, and wastes from the body. The excretory system also plays an important role in maintaining body equilibrium, or homeostasis. The human excretory system includes the lungs, sweat glands in the skin, and the urinary system (such as the kidneys and the bladder). The body uses oxygen for metabolic processes. Oxygen metabolism results in the production of carbon dioxide, which is a waste matter. The lungs expel carbon dioxide through the mouth and nose. The liver converts toxic metabolic wastes, such as ammonia, into less harmful susbtances. Ammonia is converted to urea, which is then excreted in the urine. The skin also expels urea and small amounts of ammonia through sweat. The skin is embedded with sweat glands. These glands secrete sweat, a solution of water, salt, and wastes. The sweat rises to the skin's surface, where it evaporates. The skin maintains homeostasis by producing sweat in hot environments. Sweat production cools and prevents excessive heating of the body. Each kidney contains about a million tiny structures called nephrons, which filter the blood and collect waste products, such as urea, salts, and excess water that go on to become urine. The Endocrine System — The endocrine system is involved with the control of body processes such as fluid balance, growth, and sexual development. The endocrine system controls these processes through hormones, which are produced by endocrine glands. Some endocrine glands include the pituitary gland, thyroid gland, parathyroid gland, adrenal glands, thymus gland, ovaries in females, and testes in males. The Immune System — The immune system is a network of cells, tissues, and organs that defends the body against foreign invaders. The immune system uses antibodies and specialized cells, such as T-cells, to defend the body from microorganisms that cause disease. The Reproductive System — The reproductive system includes structures, such as the uterus and fallopian tubes in females and the penis and testes in males, that allow humans to produce new offspring. The reproductive system also controls certain hormones in the human body that regulate the development of sexual characteristics and determine when the body is able to reproduce. The Integumentary System — The integumentary system is made up of a person's skin, hair, and nails. The skin acts as a barrier to the outside world by keeping moisture in the body and foreign substances out of the body. Nerves in the skin act as an interface with the outside world, helping to regulate important aspects of homeostasis, such as body temperature. Interacting Organ Systems The organ systems work together to perform complex bodily functions. The functions of regulation, nutrient absorption, defense, and reproduction are only possible because of the interaction of multiple body systems. Regulation All living organisms must maintain homeostasis, a stable internal environment. Organisms maintain homeostasis by monitoring internal conditions and making adjustments to the body systems as necessary. For example, as body temperature increases, skin receptors and receptors in a region of the brain called the hypothalamus sense the change. The change triggers the nervous system to send signals to the integumentary and circulatory systems. These signals cause the skin to sweat and blood vessels close to the surface of the skin to dilate, actions which dispel heat to decrease body temperature. Both the nervous system and the endocrine system are typically involved in the maintenance of homeostasis. The nervous system receives and processes stimuli, and then it sends signals to body structures to coordinate a response. The endocrine system helps regulate the response through the release of hormones, which travel through the circulatory system to their site of action. For example, the endocrine system regulates the level of sugar in the blood by the release of the hormones insulin, which stimulates uptake of glucose by cells, and glucagon, which stimulates the release of glucose by the liver. The nervous and endocrine systems interact with the excretory system in the process of osmoregulation, the homeostatic regulation of water and fluid balance in the body. The excretory system expels excess water, salts, and waste products. The excretion of excessive amounts of water can be harmful to the body because it reduces blood pressure. If the nervous system detects a decrease in blood pressure, it stimulates the endocrine system to release antidiuretic hormone. This hormone decreases the amount of water released by the kidneys to ensure appropriate blood pressure. Appropriate levels of carbon dioxide in the blood are also maintained by homeostatic mechanisms that involve several organ systems. Excess carbon dioxide, a byproduct of cellular respiration, can be harmful to an organism. As blood circulates throughout the body, it picks up carbon dioxide waste from cells and transports it to the lungs, where it is exhaled while fresh oxygen is inhaled. If the concentration of carbon dioxide in the blood increases above a certain threshold, the nervous system directs the lungs to increase their respiration rate to remove the excess carbon dioxide, which ensures that the levels of carbon dioxide in the blood are maintained at appropriate levels. In this way, the circulatory, respiratory, and nervous systems work together to limit the level of carbon dioxide in the blood. Nutrient Absorption To absorb nutrients from food, the nervous, digestive, muscular, excretory, and circulatory systems all interact. The nervous system controls the intake of food and regulates the muscular action of chewing, which mechanically breaks down food. As food travels through the stomach and intestines, the digestive system structures release enzymes to stimulate its chemical breakdown. At the same time, the muscular action, called peristalsis, of the muscles in the wall of the stomach help churn the food and push it through the digestive tract. In the intestines, nutrients from food travel across the surfaces of the villi. The nutrients are then picked up by the blood, and the circulatory system transports the nutrients throughout the cells of the body. The endocrine system releases hormones, such as insulin, that control the rate at which certain body cells use nutrients. Any excess minerals, such as calcium, in the blood are deposited in and stored by the skeletal system. Waste products produced by the use of nutrients, as well as the leftover solid waste from the digestion of food, exit the body through the excretory system. Throughout the process of nutrient absorption, the nervous system controls the muscles involved in digestion, circulation, and excretion. Defense Several body systems interact to defend the body from external threats. The body's first line of defense is the integumentary system, which provide a physical barrier that prevents pathogens from entering the body. The skin of the integumentary system also contains receptors for pain, temperature, and pressure. If an unpleasant stimulus is encountered, these receptors send signals to the central nervous system. In response, the central nervous system sends commands to the muscles to move the body part away from the stimulus. In this way, the integumentary, nervous, and muscular systems interact to prevent damage to the body. In the event of a break in the skin, the nervous, immune, lymphatic, and circulatory systems work together to repair the wound and protect the body from pathogens. When the skin is broken, specialized blood cells called platelets form a clot to stop the bleeding. These platelets also release chemicals that travel through the circulatory system and recruit cells, like immune system cells, to repair the wound. These immune cells, or white blood cells, are transported by the circulatory and lymphatic systems to the site of the wound, where they identify and destroy potentially pathogenic cells to prevent an infection. Some lymphocytes, white blood cells produced by the lymphatic system, also produce antibodies to neutralize specific pathogens. All of the white blood cells involved in the body's response were originally produced in the bone marrow of the skeletal system. If an infection does occur

creatinine, Uric Acid, Urea, and ammonia, non protein nitrogen

10.4 - The Haber Process & Use of NPK Fertilizers