5a.+Plant+Hormones

> //“The growth and development of a plant are influenced by genetic factors, external environmental factors, and chemical hormones inside the plant. Plants respond to many environmental factors such as light, gravity, water, inorganic nutrients, and temperature.” ~ Biology Online ~ Growth and Plant Hormones .// How does a seed ‘know’ when to germinate? How does a tree ‘know’ when to start changing leaf colour and drop it’s leaves for winter? How does a plant ‘know’ which direction to grow leaves and roots and where the light is? How does a plant ‘know’ when to produce flowers and what colour they should be? Instead of having a brain, central nervous system and endocrine system that co-ordinate communication, every plant cell can produce hormones (growth substances) that are transported throughout the plant via diffusion from cell to cell and through the xylem and phloem. ( How mobile are plant hormones?). Botanists recognize five major groups of hormones: Although plants usually appear not to move, time-lapse photography shows that plants do, in fact, move and sometimes quite quickly. There are different types of movement, tropisms and nastic movements:  Draw up a table with three columns, with each of the key concepts above in the first column, a definition in the second column and an example in the third column. You can get your information from these resources: Use digital tools to create a labelled image showing the different plant hormones, where they act (leaves, stems, roots, fruits, flowers etc) and what they do.
 * auxins
 * gibberellins
 * ethylene
 * cytokinins
 * abscisic acids
 * phototropism
 * thigmotropism
 * geotropism (or gravitropism)
 * chemotropism
 * thigmonastic movements
 * seasonal responses
 * <span style="background-color: #ffffff; color: #333333; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14.3999996185303px;">photoperiodism
 * <span style="background-color: #ffffff; color: #333333; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14.3999996185303px;"> Plant Hormones on Wikipedia
 * <span style="background-color: #ffffff; color: #333333; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14.3999996185303px;"> Growth and Plant Hormones on Biology Online
 * <span style="background-color: #ffffff; color: #333333; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14.3999996185303px;"> Plant hormones by Mary Wuerth on YouTube
 * <span style="background-color: #ffffff; color: #333333; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14.3999996185303px;"> Plant hormones by Brightstorm on YouTube
 * <span style="background-color: #ffffff; color: #333333; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14.3999996185303px;"> Plant hormones on Slideshare
 * <span style="background-color: #ffffff; color: #333333; font-family: Georgia,'Times New Roman',Times,serif; font-size: 14.3999996185303px;"> Botany lesson on Plant hormones on Slideshare