Summary

• Description:

  The PDF document comprises Form 3 Biology notes on Growth and Development.

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

  • Concept of Growth and Development
    • Defines growth as the permanent quantitative increase in size and development as the qualitative increase in complexity of an organism.
    • Outlines early embryonic development from a zygote to a blastocyst and the process of cell differentiation.
    • Compares growth in plants (localized at meristems) and animals (occurs throughout the body).
  • Measurement and Patterns of Growth
    • Explains how growth is measured using parameters like height and mass, which can be plotted to form a growth curve.
    • The Sigmoid Growth Curve: Describes the S-shaped curve typical for most organisms, detailing its four phases: lag, exponential (log), decelerating, and plateau (stationary).
    • Intermittent Growth Curve: Discusses the step-like growth pattern seen in arthropods, which is due to the shedding of their exoskeleton (moulting or ecdysis).
  • Growth and Development in Plants
    • The Seed: Covers the structure of monocotyledonous and dicotyledonous seeds.
    • Dormancy: Explains seed dormancy, its causes (e.g., chemical inhibitors, hard seed coats), and methods for breaking it (e.g., scarification).
    • Germination: Details the conditions necessary for germination (water, oxygen, suitable temperature) and describes the two main types: epigeal and hypogeal germination.
    • Primary and Secondary Growth: Explains primary growth (increase in length) from apical meristems and secondary growth (increase in girth) from cambium, leading to the formation of annual rings.
    • Plant Hormones: Discusses the roles of auxins, gibberellins, cytokinins, ethylene, and abscisic acid in regulating various aspects of plant growth, including apical dominance.
  • Growth and Development in Animals
    • Focuses on development in insects, distinguishing between complete metamorphosis (egg, larva, pupa, adult) and incomplete metamorphosis (egg, nymph, adult).
    • Explains the role of hormones, such as ecdysone and juvenile hormone, in controlling metamorphosis and moulting.
  • Practical Activities
    • Includes guides for projects and experiments, such as measuring plant growth, investigating seed structures, determining the conditions necessary for germination, and demonstrating apical dominance.

  These notes offer a detailed and structured overview of growth and development in both plants and animals. They are neatly organized, printable, and include clear explanations, diagrams, and practical activities, making them an excellent resource for students preparing for exams and for teachers planning their lessons.

• File Size:

  1.29 MB
• Length:

  23 pages
• Category:

  Lesson Notes
• Level:

  Form 3
• Subject:

  BIOLOGY
• Posted By:

  Caleb_Peter

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