Lesson Notes By Weeks and Term v4 - SHS 1
ESSENTIALS FOR SURVIVAL
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ESSENTIALS FOR SURVIVAL
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Subject: General Science
Class: SHS 1
Term: 1st Term
Week: 16
Grade code: 2.2.1.LI.3
Strand code: 2
Sub-strand code: 1
Content standard code: 2.2.1.CS.1
Indicator code: 2.2.1.LI.3
Theme: PROCESSES FOR LIVING
Subtheme: ESSENTIALS FOR SURVIVAL
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Just as our communities need a system to manage waste like the Zoomlion trucks that collect rubbish from our homes, our bodies also have a vital waste management system. This is the excretory system, with the kidneys acting as the main "waste treatment plant." When this system fails or has problems, it can lead to serious health issues. In Ghana, lifestyle choices, diet, and access to clean water can all impact the health of our excretory system. Understanding these disorders is not just for passing exams; it is essential knowledge for living a long and healthy life for ourselves and our families.
Part A: A Quick Reminder of the Healthy Excretory System
Before we discuss the problems (disorders), let's remember the key players in a healthy system. Kidneys (2): Bean-shaped organs that are the primary filters. They remove a waste product called urea from the blood, along with excess water and salts, to form urine. They are crucial for balancing water and salt levels in the body. Ureters (2): Tubes that carry urine from the kidneys to the bladder. Bladder (1): A muscular sac that stores urine, allowing urination to be infrequent and voluntary. Urethra (1): A tube through which urine passes from the bladder out of the body.
The main function is osmoregulation (balancing water and salt) and excretion (removing metabolic wastes). When this process is disrupted, disorders occur. Part B: Common Disorders of the Excretory System
We will evaluate three common and important disorders. For each, we will look at what it is, its causes, symptoms, effects, and management. Disorder 1: Kidney Stones (Renal Calculi) What are they? Kidney stones are hard, solid deposits made of minerals and salts that form inside the kidneys. They can be as small as a grain of sand or as large as a golf ball. Small stones may pass out of the body in urine without pain, but larger stones can get stuck in the ureter, causing severe pain and blocking the flow of urine. Common Causes: Dehydration: Not drinking enough water is a primary cause. When you are dehydrated, your urine becomes more concentrated, allowing minerals like calcium and uric acid to crystallize and form stones. This is a major risk in Ghana, especially during the hot, dry harmattan season. Diet: Diets high in protein, sodium (salt, e.g., in 'koobi' or processed foods), and sugar increase the risk. Certain foods like spinach and groundnuts are high in oxalates, which can contribute to stone formation in some people. Medical Conditions: Obesity, certain genetic diseases, and urinary tract infections can make stone formation more likely. Symptoms: Severe, sharp pain in the side and back, below the ribs. Pain that spreads to the lower abdomen and groin. Pain that comes in waves and fluctuates in intensity. Pain or burning sensation during urination. Pink, red, or brown urine (due to blood). Frequent need to urinate or urinating in small amounts. Evaluation of Management: Prevention (Most Effective): The best strategy is prevention. This involves drinking plenty of water (2-3 litres a day), reducing intake of salty and sugary foods, and eating a balanced diet. Treatment (for existing stones): Small Stones: Drink lots of water to flush the stone out. Pain medication may be prescribed. Large Stones: Medical procedures may be needed, such as using shock waves to break the stones into smaller pieces (lithotripsy) or surgery to remove them. Disorder 2: Urinary Tract Infections (UTIs) What are they? A UTI is an infection in any part of the urinary system—kidneys, ureters, bladder, or urethra. Most infections involve the lower urinary tract (the bladder and urethra). They are more common in females due to their shorter urethra, which makes it easier for bacteria to enter the bladder. Common Causes: Bacteria: The main cause is bacteria, most commonly *Escherichia coli* (*E. coli*), entering the urinary tract. Poor Hygiene: Wiping from back to front after using the toilet can transfer bacteria from the anus to the urethra. Holding Urine: Not urinating when you feel the urge can allow bacteria to multiply in the bladder. Symptoms: A strong, persistent urge to urinate. A burning sensation when urinating. Passing frequent, small amounts of urine. Urine that appears cloudy or has a strong smell. Pelvic pain in women. Evaluation of Management: Prevention: Good personal hygiene is key. Drink plenty of water to flush out bacteria. Urinate soon after feeling the urge. For females, wiping from front to back is crucial. Treatment: UTIs are typically treated with antibiotics prescribed by a doctor. It is very important to complete the full course of antibiotics, even if symptoms improve, to ensure the infection is completely cleared. An untreated UTI can spread to the kidneys and cause a more serious infection (pyelonephritis). Disorder 3: Kidney Failure (Renal Failure) What is it? This is a very serious condition where the kidneys lose their ability to filter waste products from the blood effectively. Waste products and excess fluid build up in the body, which can be life-threatening. Kidney failure can be acute (sudden) or chronic (happening over time). Common Causes: Chronic Diseases: The leading causes in Ghana are hypertension (high blood pressure) and diabetes. Over time, these conditions damage the small blood vessels in the kidneys. Infections: Severe, untreated infections can damage the kidneys. Medications and Toxins: Overuse of certain pain medications (non-steroidal anti-inflammatory drugs - NSAIDs) and the use of unverified herbal concoctions can be toxic to the kidneys. Physical Injury: Direct, severe injury to the kidneys. Symptoms (often subtle until advanced): Swelling in legs, ankles, or feet (edema). Reduced amount of urine. Persistent nausea and loss of appetite. Fatigue and weakness. Shortness of breath. Confusion and difficulty concentrating. Evaluation of Management: Prevention: Manage underlying conditions like diabetes and high blood pressure through medication, diet, and exercise. Avoid self-medication and use herbal remedies with extreme caution, preferably under expert guidance. Regular health check-ups are vital. Treatment (very complex and expensive): Dialysis: A medical procedure to artificially filter the blood. The patient's blood is passed through a machine (dialyzer) to remove waste and then returned to the body. This must be done several times a week and is a lifelong commitment unless a transplant is done. Kidney Transplant: A surgical procedure to replace the failed kidney with a healthy one from a donor. This is the best long-term solution but is limited by the availability of donor organs and high cost.