In this lesson our instructor talks about plant hormones and tropisms. First, she discusses plant cell signaling, auxins, cytokinins and gibberellins. She then lectures on ethylene, abscisic acid, tropisms, phytochromes and photoperiodism. Four complete example videos complete this lesson.
are produced in the apical meristem of plants and stimulate stem
elongation and phototropism as well as fruit development.
Indoleacetic acid (IAA), an auxin, occurs naturally in plants.
Cytokinins are produced in the
roots of plants and stimulate cell division and differentiation and
play a role in apical dominance.
Gibberellins promote the
elongation of plant stems and are responsible for the rapid growth
of a floral stalk, which is known as bolting.
Ethylene is a hormone that is a
gas. It stimulates fruit ripening, leaf abscission and promotes
apoptosis of plant cells.
Abscisic Acid (ABA) promotes
seed dormancy, preventing seeds from germinating until conditions
are favorable. ABA also stimulates the closure of stomata in leaves
when conditions are dry.
A tropism is a response in
which a plant turns toward or away from a stimulus. Types of tropism
include phototropism, gravitropism and thigmotropism.
Plant Hormones and Tropisms
Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.
The book and CD package include three full length practice exams that are presented with all questions answered and explained. The author also presents detailed reviews of all test topics and includes multiple-choice and free-response questions with answers at the end of each topic's chapter.
This book has a great topic-by topic breakdown of the 14 must-know principles with sample questions and answers for each of the subjects. Laboratory Review includes a focused review of all 12 AP laboratory exercises. Included in this is 2 full length practice tests that stimulate the actual test along with answers and complete explanations.
This book includes a comprehensive biology test topic review, covering everything from photosynthesis to genetics to evolution. Cracking the AP Biology also includes testing strategies for the grid-in and essay section, great guidance on writing a high-scoring essay, and two full length practice exams with detailed explanations.