Unit 7 of AP Biology delves into the fascinating world of plants, covering their structure, growth, and reproduction. Mastering this unit is crucial for success on the AP exam. This post provides a comprehensive overview of key concepts and presents multiple-choice questions (MCQs) to test your understanding. We'll explore the intricacies of plant anatomy, the processes driving growth and development, and the diverse reproductive strategies employed by plants.
Key Concepts Covered in AP Biology Unit 7:
This unit focuses on several interconnected themes. Understanding the relationships between these themes is crucial for success. We'll break down the key areas:
1. Plant Structure and Function:
- Meristems: Understand apical and lateral meristems, their roles in primary and secondary growth, and the resulting tissue types. Knowing the differences between parenchyma, collenchyma, and sclerenchyma cells is vital.
- Vascular Tissues: Master the structure and function of xylem (tracheids and vessel elements) and phloem (sieve-tube elements and companion cells). Understand water transport (cohesion-tension theory) and sugar transport (pressure-flow hypothesis).
- Plant Organs: Develop a solid grasp of the structure and function of roots, stems, and leaves, including adaptations for specific environments. Understand the role of each tissue type within each organ.
2. Plant Growth and Development:
- Hormones: Learn the roles of auxins, gibberellins, cytokinins, abscisic acid, and ethylene in regulating plant growth, development, and responses to environmental stimuli. Understand their interactions and effects on cell elongation, division, and differentiation.
- Tropisms: Comprehend phototropism, gravitropism, and thigmotropism, including the underlying mechanisms involving hormone distribution and differential growth.
- Photoperiodism: Understand the role of phytochrome in regulating flowering and other developmental processes in response to day length.
3. Plant Reproduction:
- Alternation of Generations: Master the life cycle of plants, understanding the alternation between sporophyte (diploid) and gametophyte (haploid) generations.
- Flower Structure: Learn the structure of a flower, including the roles of sepals, petals, stamens (anthers and filaments), and carpels (stigma, style, and ovary).
- Pollination and Fertilization: Understand the various methods of pollination (wind, water, animals) and the processes of both pollination and fertilization, leading to seed development.
- Seed Germination: Understand the environmental factors that affect seed germination and the process of embryo development.
- Asexual Reproduction: Understand vegetative propagation and other forms of asexual reproduction in plants.
AP Biology Unit 7 MCQ Practice Questions:
Now, let's test your knowledge with some practice MCQs. Remember to analyze your answers and review the relevant concepts if needed.
1. Which of the following tissues is responsible for the primary growth of a plant? (a) Sclerenchyma (b) Vascular cambium (c) Apical meristem (d) Cork cambium
2. The cohesion-tension theory explains the movement of: (a) Sugars in the phloem (b) Water in the xylem (c) Hormones in the parenchyma (d) Ions in the apoplast
3. Which plant hormone is primarily responsible for promoting fruit ripening? (a) Auxin (b) Gibberellin (c) Cytokinin (d) Ethylene
4. The process by which plants respond to the length of day and night is known as: (a) Gravitropism (b) Phototropism (c) Thigmotropism (d) Photoperiodism
5. In the alternation of generations, the diploid generation is called the: (a) Gametophyte (b) Sporophyte (c) Zygote (d) Gamete
Answer Key: 1. (c), 2. (b), 3. (d), 4. (d), 5. (b)
This is just a starting point. Thorough review of your textbook, class notes, and additional practice questions are essential for mastering this unit. Good luck with your AP Biology studies!
