Home Economics - Junior Secondary 1 - The human body IV

TERM: 1^ST TERM

WEEK: 6

CLASS: Junior Secondary School 1

AGE: 12 years

DURATION: 40 minutes each for 2 periods

DATE:

SUBJECT: Home economics

TOPIC: The human body IV

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

1.) Discuss the structure and parts of the skin

2.) State the functions of the skin

3.) Outline the care and grooming of the skin

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

INSTRUCTIONAL MATERIALS: Recommended Home economics textbooks for Junior Secondary School 1

INSTRUCTIONAL PROCEDURES: PERIOD 1-2:

NOTE

THE HUMAN BODY

Structure and Parts of the Skin:

The skin is the largest organ of the body and serves as a protective barrier between the internal body and the external environment. It consists of three main layers:

1. Epidermis:

• The outermost layer of the skin.
• Structure: Composed of several sub-layers of cells. The outermost layer consists of dead, keratinized cells that are continuously shed and replaced.
• Functions: Acts as the first line of defense against environmental threats like bacteria, UV rays, and pollutants. The epidermis also contains melanocytes that produce melanin, the pigment responsible for skin color.

2 Dermis:

• The middle layer of the skin, beneath the epidermis.
• Structure: Made up of connective tissue, including collagen and elastin fibers, which provide strength and elasticity. The dermis contains blood vessels, nerves, hair follicles, sweat glands, and sebaceous (oil) glands.
• Functions: Supports and nourishes the epidermis, enables skin elasticity and strength, and helps regulate body temperature through sweat production and blood flow.

3 Hypodermis (Subcutaneous Layer):

• The deepest layer of the skin, located beneath the dermis.
• Structure: Composed mainly of fat and connective tissue.
• Functions: Insulates the body, stores energy in the form of fat, and provides cushioning to protect internal organs and bones.

Functions of the Skin:

The skin has several important functions that help maintain overall body health:

1 Protection:

• Acts as a barrier to protect the internal organs from harmful microorganisms, chemicals, and physical damage (e.g., abrasions, UV radiation).

2 Temperature Regulation:

• Through sweat production and regulation of blood flow, the skin helps maintain a stable internal body temperature. When the body is hot, sweat evaporates from the skin to cool it, and when the body is cold, blood vessels constrict to preserve heat.

3 Sensory Reception:

• The skin contains sensory receptors that detect touch, pain, pressure, and temperature, sending signals to the brain to interpret various sensations.

4 Excretion:

• The skin excretes waste products like urea, salts, and excess water through sweat glands.

5 Vitamin D Synthesis:

• The skin produces vitamin D when exposed to sunlight, which is essential for calcium absorption and bone health.

6 Immune Function:

• The skin contains immune cells, like Langerhans cells, which help detect and fight off infections and pathogens.

Care and Grooming of the Skin:

1 Cleanse Regularly:

• Gently cleanse the skin using a mild soap or cleanser suitable for your skin type (oily, dry, sensitive). This helps remove dirt, oil, and dead skin cells without stripping the skin of its natural oils.

2 Moisturize:

• Use a moisturizer to keep the skin hydrated and prevent dryness. Choose a moisturizer based on your skin type, and apply it after cleansing to lock in moisture.

3 Protect from the Sun:

• Always use sunscreen with a broad-spectrum SPF of at least 30, even on cloudy days, to protect the skin from harmful UV rays that cause premature aging and increase the risk of skin cancer.

4 Exfoliate:

• Regular exfoliation (1-2 times a week) helps remove dead skin cells and promotes the growth of new, healthy skin. Use gentle exfoliants suited to your skin type to avoid irritation.

5 Hydrate and Nourish:

• Drink plenty of water to keep the skin hydrated from the inside out. A balanced diet with vitamins and minerals also promotes healthy skin.

6 Avoid Harsh Chemicals:

• Avoid skin products that contain harsh chemicals, fragrances, or alcohol, which can irritate the skin or lead to dryness. Opt for products with natural ingredients if you have sensitive skin.

7 Sleep and Stress Management:

• Proper sleep and stress management are crucial for skin health. Stress and lack of sleep can lead to skin problems like acne, eczema, and premature aging.

EVALUATION:

1. Describe the three main layers of the skin and explain the function of each layer.
2. What role does the skin play in regulating body temperature, and how does it perform this function?
3. List and explain at least three functions of the skin that contribute to overall body health.
4. What are the key steps in proper skin care and grooming, and why is each step important?
5. How does the skin protect the body from external environmental factors, and what are some common ways to enhance this protection?

CLASSWORK: As in evaluation

CONCLUSION: The teacher marks their books and commends them positively