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: 13
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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This lesson focuses on the disorders that can affect our excretory system, particularly the kidneys. The excretory system acts as the body's essential waste management and water balancing system. In Ghana, lifestyle diseases like hypertension and diabetes are on the rise, and these are major causes of kidney problems. Understanding these disorders, their causes, and how to prevent them is crucial for maintaining personal health and for understanding major public health challenges in our communities. This lesson will equip learners with the knowledge to make informed health choices and to "evaluate" or make judgements about the seriousness and management of these conditions.
A. Quick Recap: The Healthy Excretory System
Before we discuss what can go wrong, let's remember the key players and their jobs. Organs: The main organs are the two kidneys, the ureters (tubes), the urinary bladder (storage bag), and the urethra (exit tube). Main Function of Kidneys: Filtration: They act like a very fine sieve or filter, cleaning your blood. They remove a waste product called urea, excess salts, and excess water. Regulation: They control the amount of water in your body (osmoregulation) and maintain the correct balance of salts and minerals (ions). Urine Formation: The filtered waste (urea, excess water, and salts) becomes urine. Analogy: Think of the kidneys as the workers at a water purification plant, cleaning the body's "water supply" (blood). The ureters are the pipes leading to a storage tank (the bladder), and the urethra is the final tap. B. Common Disorders of the Excretory System
When this system is not working well, it leads to serious health problems. Let's evaluate three major ones. Kidney Stones (Nephrolithiasis) What They Are: These are hard, solid masses that form in the kidneys. They are made of crystallised minerals and salts that are normally found in urine. They can be as small as a grain of sand or as large as a small stone (pebble). How They Form (The Cause): Kidney stones form when your urine becomes too concentrated. This allows minerals like calcium, oxalate, and uric acid to crystallise and stick together. Primary Cause: Dehydration (not drinking enough water). When you don't drink enough, your urine is more concentrated, like a thick soup instead of a clear broth, making it easier for crystals to form. Other Causes: Diet: A diet very high in salt, sugar, and protein can increase the risk. Genetics: Sometimes, it runs in families. Medical Conditions: Certain infections or conditions can increase the risk. Symptoms: Severe, sharp pain in the back, side, or lower abdomen. This pain can come in waves. Pain or a burning sensation during urination. Urine that looks pink, red, or brown (due to blood). Cloudy or bad-smelling urine. Frequent need to urinate. Prevention and Management: Prevention is Key: DRINK PLENTY OF WATER! Aim for 2-3 litres per day. In our hot Ghanaian climate, this is very important. Your urine should be light yellow or clear. Dietary Changes: Reduce your intake of salty foods (e.g., some processed foods, koobi) and manage your protein intake. Management: Small stones may pass on their own with lots of water and pain medication. Larger stones may require medical procedures to break them up or remove them surgically. Urinary Tract Infections (UTIs) What They Are: An infection in any part of the urinary system—kidneys, ureters, bladder, or urethra. Most UTIs involve the lower urinary tract (the bladder and urethra). The Cause: UTIs are typically caused by bacteria, most commonly *Escherichia coli* (*E. coli*), which normally live in the digestive system. These bacteria can enter the urethra and travel up to the bladder, where they multiply. UTIs are more common in females because their urethra is shorter, making it easier for bacteria to reach the bladder. Symptoms: A strong, persistent urge to urinate. A burning feeling or pain when urinating. Passing frequent, small amounts of urine. Urine that appears cloudy. Pelvic pain in women. Prevention and Management: Good Hygiene: Wiping from front to back after using the toilet to prevent bacteria from the anus from entering the urethra. Hydration: Drinking plenty of water helps to flush bacteria out of the urinary system. Urination Habits: Urinating soon after you feel the urge; don't hold it in for too long. Management: UTIs are treated with antibiotics prescribed by a doctor or a nurse at a clinic. It is important to complete the full course of medication even if you start feeling better. Kidney Failure (Renal Failure) What It Is: This is the most serious condition. It occurs when the kidneys lose their ability to filter waste products from the blood effectively. It can be Acute (happens suddenly) or Chronic (happens gradually over months or years). We will focus on Chronic Kidney Disease (CKD). The Causes (Very important in the Ghanaian context): Hypertension (High Blood Pressure): Uncontrolled high blood pressure damages the small blood vessels in the kidneys over time, making them unable to filter blood properly. This is a leading cause in Ghana. Diabetes (Type 2): High blood sugar levels damage the filtering units of the kidneys (the nephrons). This is another leading cause. Infections: Untreated infections like glomerulonephritis (inflammation of the kidney's filters) can lead to failure. Misuse of Drugs: Overuse of certain painkiller drugs (NSAIDs) can damage the kidneys. Use of Unverified Herbal Concoctions: Some herbal medicines can be toxic to the kidneys (nephrotoxic) and cause severe damage. It is dangerous to take remedies without knowing what they contain or their effect on the body. Symptoms: Symptoms are often not noticeable until the damage is advanced. Swelling (edema) in the legs, ankles, or feet. Constant tiredness and lack of energy (fatigue). Shortness of breath. Nausea and vomiting. Reduced amount of urine. Management: Early Stages: Managing the underlying cause (controlling blood pressure and blood sugar), dietary changes (low salt, low potassium). Advanced Stages (End-Stage Renal Disease): Dialysis: A medical procedure where a machine acts as an artificial kidney to filter the blood. It is very expensive and time-consuming (patients often need it 3 times a week for several hours). Kidney Transplant: A surgical procedure to place a healthy kidney from a donor into the patient's body. This is a major surgery and also very costly and requires lifelong medication.
Guided Practice (With Solutions)