dart2
New Member
I have been learning alot from this site and wanted to share this link. I wanted to understand the entire plant germination process further and this movie hit the mark. The site is full of amazing Time-lapse plant movies. 
Although our lives depend on plants for virtually everything that keeps us alive (oxygen, food, fibers, lumber, fuel, etc), their lives remain a secret to most of us. The reason is simple - plants live on a different time-scale from ours. Although not usually obvious in the relatively hyperactive activities of humans, plants are in constant motion as they develop, search for light and nutrients, avoid predators, exploit neighbors, and reproduce.
Time-lapse photography allows us to easily see the movements of plants and clearly demonstrates that plants are living organisms capable of some extraordinary things. Time-lapse photography is done by capturing a series of images at intervals ranging from seconds to hours apart. When the images are viewed in rapid succession, much like a flip book, the effect is to compress into a short period, the changes that occurred over a relatively long period of time. The movies on this site show a variety of plants living out their dynamic lives. While we especially hope this site provides material that may captivate the interest of budding plant biologists, even the seasoned plant biologists will find interesting material. New movies will be added to the site as we make or obtain them. However, since making time-lapse movies requires considerable patience, time, and some luck, the rate at which new movies will appear is unpredictable. Other educational material are also becoming available on the site. In the meantime, we hope you enjoy the material that is available now.
This site is intended to serve as a resource for nonprofit educational use. Feel free to include a link to this site in your web page or copy movies for in-class presentations. However, copies of the movies may not be included on other web sites. In some circumstances, "for-profit" use may be arranged (higher resolution versions of some movies are available). The rights to the contents of this site belong to Roger P. Hangarter and Indiana University unless otherwise indicated.
Seed germination
For non-dormant seeds, germination starts when a seed is provided with water as long as the temperature is appropriate. The uptake of water by dry seed is called imbibition (imbibition means to drink: seeds imbibe water, you do not imbibe seeds). As seeds imbibe water, they expand and enzymes and food supplies become hydrated. Hydrated enzymes become active and the seed increase its metabolic activities to produce energy for the growth process. In addition, the water causes turgor pressure to increase in the cells and they are able to enlarge.
As you will see in the movies of germinating seeds, the first part of the seedling to emerge from the seed coat is the root (also called the radical). The emergence of the root is typically used as the first indication that a seed is viable. Eventually the shoot will also expand and emerge from the seed.
If germination occurs in darkness, root growth slows after the shoot emerges and shoot elongation accelerates. This behavior increases the chance that the seedling will emerge from soil into the light where it will be able to obtain energy from sunlight by photosynthesis. Once a seedling emerges into the light, the plant undergoes dramatic changes such as turning green and producing leaves. This light-dependent developmental transformation is called photomorphogenesis.
©2000 Roger P. Hangarter and Indiana University. All rights reserved.
Created for nonprofit educational use
by
Roger P. Hangarter
Indiana University, Department of Biology, 915 E 3rd St, Bloomington, IN 47405
by
Roger P. Hangarter
Indiana University, Department of Biology, 915 E 3rd St, Bloomington, IN 47405
Although our lives depend on plants for virtually everything that keeps us alive (oxygen, food, fibers, lumber, fuel, etc), their lives remain a secret to most of us. The reason is simple - plants live on a different time-scale from ours. Although not usually obvious in the relatively hyperactive activities of humans, plants are in constant motion as they develop, search for light and nutrients, avoid predators, exploit neighbors, and reproduce.
Time-lapse photography allows us to easily see the movements of plants and clearly demonstrates that plants are living organisms capable of some extraordinary things. Time-lapse photography is done by capturing a series of images at intervals ranging from seconds to hours apart. When the images are viewed in rapid succession, much like a flip book, the effect is to compress into a short period, the changes that occurred over a relatively long period of time. The movies on this site show a variety of plants living out their dynamic lives. While we especially hope this site provides material that may captivate the interest of budding plant biologists, even the seasoned plant biologists will find interesting material. New movies will be added to the site as we make or obtain them. However, since making time-lapse movies requires considerable patience, time, and some luck, the rate at which new movies will appear is unpredictable. Other educational material are also becoming available on the site. In the meantime, we hope you enjoy the material that is available now.
This site is intended to serve as a resource for nonprofit educational use. Feel free to include a link to this site in your web page or copy movies for in-class presentations. However, copies of the movies may not be included on other web sites. In some circumstances, "for-profit" use may be arranged (higher resolution versions of some movies are available). The rights to the contents of this site belong to Roger P. Hangarter and Indiana University unless otherwise indicated.
Seed germination
For non-dormant seeds, germination starts when a seed is provided with water as long as the temperature is appropriate. The uptake of water by dry seed is called imbibition (imbibition means to drink: seeds imbibe water, you do not imbibe seeds). As seeds imbibe water, they expand and enzymes and food supplies become hydrated. Hydrated enzymes become active and the seed increase its metabolic activities to produce energy for the growth process. In addition, the water causes turgor pressure to increase in the cells and they are able to enlarge.
As you will see in the movies of germinating seeds, the first part of the seedling to emerge from the seed coat is the root (also called the radical). The emergence of the root is typically used as the first indication that a seed is viable. Eventually the shoot will also expand and emerge from the seed.
If germination occurs in darkness, root growth slows after the shoot emerges and shoot elongation accelerates. This behavior increases the chance that the seedling will emerge from soil into the light where it will be able to obtain energy from sunlight by photosynthesis. Once a seedling emerges into the light, the plant undergoes dramatic changes such as turning green and producing leaves. This light-dependent developmental transformation is called photomorphogenesis.
©2000 Roger P. Hangarter and Indiana University. All rights reserved.
