IB Grade-12 Biology | Theme D: Continuity and Change by Prakhar Chauhan | Learn Smarter
K12 Students

Academics

AI-Powered learning for Grades 8–12, aligned with major Indian and international curricula.

Academics

Grades

Grade 8 Grade 9 Grade 10 Grade 11 Grade 12

Curriculum

CBSE ICSE IB
Professionals

Professional Courses

Industry-relevant training in Business, Technology, and Design to help professionals and graduates upskill for real-world careers.

Professional Courses
Games

Interactive Games

Fun, engaging games to boost memory, math fluency, typing speed, and English skills—perfect for learners of all ages.

games
Typing
Memory
Math
English Adventures
Knowledge
Theme D: Continuity and Change

The chapter explores essential biological processes including DNA replication, protein synthesis, and cell division, highlighting key molecular mechanisms and their implications for genetics and inheritance. It further discusses gene expression, water potential in cells, reproduction, and the principles of natural selection and ecosystem dynamics. The interactions between species and their environment, along with the challenges posed by climate change, are presented as vital concepts in understanding biological continuity and change.

Enroll to start learning

You’ve not yet enrolled in this course. Please enroll for free to listen to audio lessons, classroom podcasts and take mock test.

Sections

  • 1

    Molecules

    This section discusses molecules with a focus on DNA replication, protein synthesis, and mutations.

    Learning Practice

  • 1.1

    Dna Replication

    DNA replication is the semi-conservative process by which a cell duplicates its DNA, ensuring each daughter cell receives an exact copy.

    Learning Practice

  • 1.2

    Protein Synthesis

    Protein synthesis is the process by which cells convert genetic information from DNA into functional proteins through transcription and translation.

    Learning Practice

  • 1.3

    Mutation And Gene Editing

    This section covers the impacts of mutations on DNA sequences and explores gene editing techniques like CRISPR-Cas9.

    Learning Practice

  • 2

    Cells

    Cell division is essential for growth, repair, and reproduction, comprising nuclear division and cytokinesis.

    Learning Practice

  • 2.1

    Cell And Nuclear Division

    Cell and nuclear division is essential for growth, repair, and reproduction, involving processes like mitosis and meiosis.

    Learning Practice

  • 2.2

    Gene Expression (Hl Only)

    Gene expression is the process through which genetic information is translated into functional gene products, primarily proteins.

    Learning Practice

  • 2.3

    Water Potential

    Water potential is a crucial concept in biology that indicates the direction of water movement in plants and cells.

    Learning Practice

  • 3

    Organisms

    This section covers reproduction, inheritance, and homeostasis in organisms, explaining key biological processes that ensure species continuity and the transmission of genetic information.

    Learning Practice

  • 3.1

    Reproduction

    Reproduction is the biological process by which organisms produce offspring, ensuring the continuity of species.

    Learning Practice

  • 3.2

    Inheritance

    Inheritance involves the transmission of genetic information from parents to offspring, determining traits across generations.

    Learning Practice

  • 3.3

    Homeostasis

    Homeostasis refers to the processes that maintain a stable internal environment within an organism.

    Learning Practice

  • 4

    Ecosystems

    Ecosystems involve interactions between organisms and their environment, highlighting concepts like natural selection, ecological stability, and the effects of climate change.

    Learning Practice

  • 4.1

    Natural Selection

    Natural selection drives the gradual evolution of species through advantageous traits over generations.

    Learning Practice

  • 4.2

    Stability And Change

    Ecosystems experience both stability and change over time due to ecological succession, resilience, and biodiversity.

    Learning Practice

  • 4.3

    Climate Change

    Climate change refers to long-term alterations in temperature, precipitation, and other atmospheric conditions, resulting from various anthropogenic factors.

    Learning Practice

References

Untitled document (12).pdf

Class Notes

Memorization

What we have learnt

  • DNA replication is a semi-c...
  • Protein synthesis involves ...
  • Mutations and gene editing ...

Final Test

Revision Tests