Lesson Notes By Weeks and Term - Senior Secondary 2

TERM – 1^ST TERM

WEEK TWO

Class: Senior Secondary School 2

Age: 16 years

Duration: 40 minutes of 5 periods each

Date:

Subject: Biology

Topic: TRANSPORT SYSTEM 1

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

1. Define transport system
2. Identify the importance of diffusion and osmosis to transport system.

iii. Discuss transport system in higher organisms.

1. Identify the materials for transport

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

INSTRUCTIONAL MATERIALS: Videos, loud speaker, textbook, pictures

INSTRUCTIONAL PROCEDURES

PERIOD 1-2

NOTE

TRANSPORT SYSTEM

A transport system in refers to the network of structures and processes that facilitate the movement of substances within an organism. This system ensures the distribution of essential materials, such as nutrients, gases, hormones, and waste products, to and from cells. The efficiency of a transport system is crucial for the proper functioning, growth, and maintenance of an organism.

In animals, the circulatory system, comprising the heart, blood vessels, and blood, is a prominent example of a transport system. It transports oxygen, nutrients, and other vital substances throughout the body.

In plants, the vascular system, which includes xylem and phloem, serves as the transport system. Xylem transports water and minerals from the roots to the rest of the plant, while phloem transports sugars produced during photosynthesis to various plant tissues.

Importance of diffusion and osmosis to transport system

Diffusion and osmosis are fundamental processes that play crucial roles in various transport systems, ensuring the movement of substances within and between cells. Here's their importance:

1. Cellular Nutrient Exchange: Here diffusion allows small molecules, such as oxygen and nutrients, to move freely across cell membranes. Cells obtain necessary substances for energy production and metabolic processes through diffusion.
2. Waste Removal: In waste removal, diffusion facilitates the movement of waste products, like carbon dioxide, out of cells. This is essential for maintaining proper cellular function and preventing the buildup of harmful substances.
3. Water Regulation: Osmosis controls the movement of water across cell membranes. Cells maintain their shape and function by regulating the balance of water through osmotic processes.
4. Plant Nutrition and Hydration: Osmosis is vital for the absorption of water and minerals by plant roots. This process helps in maintaining turgor pressure, which is crucial for plant structure and support.
5. Gas Exchange in Respiratory Systems: Diffusion enables the exchange of gases, such as oxygen and carbon dioxide, in respiratory systems. This is critical for supplying oxygen to tissues and removing carbon dioxide, a byproduct of cellular respiration.
6. Circulatory Systems: Diffusion aids in the movement of gases and nutrients across blood vessel walls. In capillaries, substances like oxygen and nutrients diffuse from the blood to surrounding tissues, while waste products move into the blood.

Transport system in larger organisms (plants and animals)

In larger organisms, the transport system is more complex and typically involves specialized structures to facilitate the movement of substances throughout the body.

 Plants

1. Vascular System:

   - Xylem: Transports water and minerals from the roots to the rest of the plant. It is a unidirectional transport.

   - Phloem: Transports sugars produced during photosynthesis from leaves to other plant tissues. It can transport in both directions.

2. Root System:

   - Root Hairs: Increase the surface area for water and mineral absorption.

3. Stomata:

   - Pores on leaves and stems that regulate gas exchange, allowing the plant to take in carbon dioxide for photosynthesis and release oxygen.

Animals

The transport system in animals involves the coordination of various structures and processes to move essential substances throughout the body. The primary systems responsible for this transport are the circulatory, respiratory, digestive, excretory, and endocrine systems:

1. Circulatory System:

   - Heart: Pumps blood to circulate throughout the body.

   - Blood Vessels (Arteries, Veins, Capillaries): Arteries carry oxygenated blood away from the heart, veins return deoxygenated blood to the heart, and capillaries facilitate nutrient and gas exchange at the tissue level.

2. Respiratory System:

   - Lungs (in mammals): Facilitate the exchange of oxygen and carbon dioxide between the air and the bloodstream.

3. Digestive System:

   - Stomach and Intestines: Involved in the digestion and absorption of nutrients.

   - Liver and Pancreas: Produce enzymes and substances that aid in digestion.

4. Excretory System:

   - Kidneys: Filter blood, remove waste products, and regulate water and electrolyte balance.

   - Urinary System: Includes the ureters, bladder, and urethra for the storage and elimination of urine.

5. Endocrine System:

   - Endocrine Glands (e.g., Thyroid, Pancreas): Secrete hormones that regulate various physiological processes, and these hormones are transported by the circulatory system.

6. Immune System:

   - White Blood Cells: Play a crucial role in defending the body against pathogens.

   - Lymphatic System: Supports immune function and returns excess fluid from tissues to the bloodstream.

 Importance of Transport System

1. Nutrient Distribution: In Circulatory System (Animals) / Vascular System (Plants), transport system ensures the efficient distribution of nutrients, oxygen, and hormones to cells and tissues.
2. Waste Removal: Transport system facilitates the removal of metabolic waste products from cells.
3. Gas Exchange: It's enables the exchange of oxygen and carbon dioxide in animals, while facilitating the exchange of gases, allowing for photosynthesis and respiration.
4. Temperature Regulation: It's helps distribute heat throughout the body in animals and assists in the transport of water, contributing to temperature regulation.
5. Fluid Balance: It maintains fluid balance by regulating water and electrolyte levels in animals, while assisting in maintaining turgor pressure, crucial for plant structure.

 Materials for Transport Structures

1. Arteries (Animals): Arteries have three layers - the tunica externa, tunica media, and tunica intima. Materials include, Elastic fibers (for flexibility), smooth muscle cells (for vessel contraction), collagen (provides strength).
2. Veins (Animals): Veins have similar layers to arteries but with thinner walls. Materials for transport include, Collagen, elastic fibers, smooth muscle cells, valves (to prevent backflow of blood).
3. Vascular Bundles (Plants):

- Xylem: Materials for transport in xylem include, Tracheids and vessel elements (conduct water), fibers (provide structural support).

- Phloem: Materials are, sieve tube elements (transport sugars), companion cells (support sieve tube function), fibers.

EVALUATION: 1. What is transport system

2. Discuss the importance of diffusion and osmosis to transport system
3. Identify 3 materials for transport

CLASSWORK: As in evaluation

CONCLUSION: The teacher commends the students positively