Lesson Notes By Weeks and Term - Senior Secondary 2

TERM – 2^ND TERM

WEEK NINE

Class: Senior Secondary School 2

Age: 16 years

Duration: 40 minutes of 5 periods each

Date:

Subject: Biology

Topic: REGULATION OF INTERNAL ENVIRONMENT

SPECIFIC OBJECTIVES: At the end of the lesson, pupils should be able to

1. Define homeostasis
2. Identify the organs and processes of homeostasis.

iii. Describe the structure, functions and diseases of the kidney

1. Discuss the effects of kidney diseases and their remedies

INSTRUCTIONAL TECHNIQUES: Identification, explanation, questions and answers, demonstration, videos from source

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

NOTE

REGULATION OF INTERNAL ENVIRONMENT

Homeostasis is the physiological process through which an organism maintains a stable internal environment, despite external changes. It involves a series of mechanisms and feedback loops that regulate various physiological parameters such as temperature, pH, and concentrations of ions and gases within a narrow range, conducive to the proper functioning of cells and tissues.

Organs and Processes Involved in Homeostasis

1. Brain (Hypothalamus): The brain acts as the control center for homeostasis, receiving and processing information from the body.

   - Processes: Regulates body temperature, thirst, hunger, and circadian rhythms.

2. Endocrine System (Hormones):

   - Organs: Glands like the pituitary, thyroid, adrenal glands.

   - Processes: Release hormones that regulate metabolism, blood sugar, salt balance, and stress responses.

3. Nervous System:

   - Organs: Brain and peripheral nerves.

   - Processes: Nerve impulses transmit information quickly for rapid responses, e.g., reflex actions.

4. Kidneys: Regulate water and ion balance, and remove waste products from the blood.

   - Processes: Filtration, reabsorption, and secretion to maintain proper blood composition.

5. Liver: Metabolic regulation and detoxification.

   - Processes: Controls blood glucose levels, stores and releases nutrients, detoxifies harmful substances.

6. Lungs: Regulate oxygen and carbon dioxide levels in the blood.

   - Processes: Breathing (respiration) controls gas exchange.

7. Skin: Regulates body temperature through sweat production and vasodilation/constriction of blood vessels.

   - Processes: Cooling the body through evaporation of sweat, or conserving heat through vasoconstriction.

8. Pancreas: Regulates blood sugar levels.

   - Processes: Releases insulin to lower blood sugar and glucagon to raise it.

9. Blood: Transports nutrients, gases, and waste products.

    - Processes: Maintains pH balance, osmotic pressure, and temperature.

 Structure of the Kidney

The kidneys are bean-shaped organs located in the back of the abdominal cavity, one on each side of the spine. Each kidney consists of three main regions: the renal cortex (outer region), renal medulla (middle region), and renal pelvis (inner region). The functional unit of the kidney is the nephron, which is responsible for filtering blood and forming urine.

Function of the Kidney

1. Filtration: The nephrons filter blood, removing waste products, excess ions, and water.
2. Reabsorption: Essential substances like water, glucose, and ions are reabsorbed into the bloodstream.
3. Secretion: Additional waste products are actively transported into the urine.
4. Regulation of Blood Pressure: The kidneys help control blood pressure by adjusting the volume of blood and releasing the enzyme renin.
5. Erythropoiesis Regulation: Produces and releases erythropoietin, stimulating red blood cell production.

Common Kidney Diseases

1. Chronic Kidney Disease (CKD): Gradual loss of kidney function over time.
2. Acute Kidney Injury (AKI): Sudden and temporary loss of kidney function, often due to severe dehydration or other underlying conditions.
3. Kidney Stones: Hard deposits of minerals and salts that form in the kidneys and may cause pain and blockage.
4. Polycystic Kidney Disease (PKD): Genetic disorder leading to the formation of fluid-filled cysts in the kidneys.
5. Urinary Tract Infections (UTIs): Infections affecting the kidneys, ureters, bladder, or urethra.

Effects of Kidney Diseases

1. Decreased Filtration: Impaired ability to filter waste from the blood, leading to a buildup of toxins.
2. Fluid and Electrolyte Imbalance: Disruption in water and electrolyte regulation.
3. Hypertension: Kidney dysfunction can contribute to high blood pressure.
4. Anemia: Reduced production of erythropoietin affects red blood cell production.
5. Bone Disorders: Imbalance in calcium and phosphorus levels can affect bone health.
6. Cardiovascular Complications: Increased risk of heart-related problems due to fluid and electrolyte imbalances.

Possible Remedies and Treatments

1. Medication: Depending on the specific kidney disease, medications may be prescribed to manage symptoms or slow the progression.
2. Dietary Changes: A controlled diet may help manage conditions like hypertension, diabetes, or kidney stones.
3. Fluid Management: Proper hydration is crucial, but fluid intake may need adjustment based on the type of kidney disease.
4. Dialysis: For advanced kidney failure, dialysis may be necessary to perform the functions of the kidneys artificially.
5. Kidney Transplant: In cases of severe kidney damage, transplantation may be considered.

EVALUATION: 1. Define Homeostasis

2. Discuss 4 organs and processes involved in homeostasis
3. Describe the possible remedies and treatment for kidney diseases.
4. Identify 4 Effects of kidney diseases.

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively