Summary

• Description:

  The PDF document comprises Form 4 Biology notes on Reception, Response, and Co-ordination in Plants and Animals.

  The topics and sub-topics covered in the document include:

  • Introduction to Irritability
    • Defines key concepts such as irritability, stimulus, response, reception, and co-ordination as fundamental characteristics of living organisms.
  • Reception and Response in Plants
    • Tropisms: Detailed explanations of directional growth movements in response to stimuli, including phototropism (light), geotropism (gravity), hydrotropism (water), chemotropism (chemicals), and thigmotropism (touch). The role of auxins in causing these responses is highlighted.
    • Tactic and Nastic Movements: Differentiates between tactic movements (directional movement of a whole organism) and nastic movements (non-directional response of a plant part).
    • Plant Hormones: Discusses the effects of auxins on plant growth, such as apical dominance, development of adventitious roots, and parthenocarpy (fruit formation without fertilization).
  • Reception and Response in Animals
    • The Nervous System: Covers the components of the central and peripheral nervous systems. It details the structure and function of the three types of neurons (sensory, motor, and intermediate) and explains the transmission of nerve impulses across a synapse.
    • The Human Brain and Spinal Cord: Describes the major parts of the brain (cerebrum, cerebellum, medulla oblongata) and their functions in coordinating body activities.
    • Reflex Actions: Explains the simple reflex arc and the concept of conditioned (learned) reflexes.
    • The Endocrine System: Discusses the role of hormones as chemical messengers. A comprehensive table outlines the major endocrine glands, the hormones they secrete (e.g., insulin, adrenaline, thyroxine), their functions, and the effects of over-secretion or under-secretion. A comparison between the nervous and endocrine systems is also provided.
    • Drug Abuse: Lists the harmful effects of various drugs on human health.
  • The Sense Organs
    • The Human Eye: Provides a detailed, labeled diagram and explains the structure and function of each part. It covers the process of accommodation (focusing on near and distant objects) and common eye defects (short-sightedness, long-sightedness) and their correction.
    • The Human Ear: Describes the structure of the outer, middle, and inner ear. It explains the mechanism of hearing and the role of the semicircular canals in maintaining balance and posture. Common ear defects and their causes are also mentioned.
  • Practical Activities
    • Includes guides for hands-on experiments to investigate tactic responses, tropisms in seedlings, the phenomenon of etiolation, the blind spot in the human eye, and the knee-jerk reflex.

  These notes are comprehensive, neatly organized, and printable, making them an excellent resource for students studying the complex systems of response and co-ordination. They are also highly suitable for teachers to use for lesson preparation, providing clear explanations, diagrams, and practical activity guides to enhance learning.

• File Size:

  479.91 KB
• Length:

  27 pages
• Category:

  Lesson Notes
• Level:

  Form 4
• Subject:

  BIOLOGY
• Posted By:

  Caleb_Peter

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