Learn about Growth and Development in Plants and Animals in Class 12 Biology. Understand primary and secondary growth in plants, growth correlations, abnormal development, regeneration, and embryonic induction. In animals, explore fertilization, notochord, and mesoderm formation.
This exam-focused guide helps students prepare easily for Punjab Board Biology exams with clear and concise notes.
📥 Download Class 12 Biology Unit 19 – Growth and Development Notes PDF
Skip to PDF contentGet complete and exam-focused Class 12 Biology Unit 19 – Growth and Development notes in one PDF. These notes are specially prepared for Punjab Board students to help you study easily and score better in exams.
👉 Download PDF: Class 12 Biology Unit 19 – Growth and Development Notes PDF
- Covers Growth in Plants and Animals
- Includes Primary & Secondary Growth, Regeneration, Abnormal Development
- Explains Fertilization, Notochord, and Mesoderm Formation
- Exam-focused & Students-friendly
❓ FAQs – Class 12 Biology Unit 19 Notes
Q1: What is the main difference between primary and secondary growth?
Primary growth increases length (apical meristem), while secondary growth increases thickness (vascular cambium).
Q2: Define regeneration. Give one example.
Regeneration is the replacement of lost or damaged parts. Example: Starfish regrowing its arm.
Q3: What is embryonic induction?
It is when one group of cells influences nearby cells to develop into specific tissues or organs.
Q4: What is the role of the notochord?
The notochord provides support in early embryo development and helps in organizing body structure.
Q5: What is abnormal development?
Abnormal development is faulty growth or differentiation that can cause deformities or unusual structures.
📝 MCQs – Growth and Development
Q1: Primary growth in plants is due to:
- Vascular cambium
- Apical meristem ✅
- Intercalary meristem
- Cork cambium
Q2: Secondary growth in plants results in:
- Increase in length
- Increase in thickness ✅
- Formation of flowers
- Seed germination
Q3: Regeneration refers to:
- Growth in length
- Replacement of lost or damaged parts ✅
- Formation of flowers
- Increase in thickness
Q4: Embryonic induction is:
- Rapid cell division
- Influence of one group of cells on nearby cells to differentiate ✅
- Formation of seeds
- Secondary growth
Q5: Which meristem is responsible for secondary growth in plants?
- Apical meristem
- Intercalary meristem
- Vascular cambium ✅
- Root cap
Q6: Fertilization is important because:
- It increases plant thickness
- It combines male and female gametes to form a zygote ✅
- It regenerates lost parts
- It forms the notochord