37 - 37 Regulation of Plant Growth 37 Regulation of Plant...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon
37 Regulation of Plant Growth
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
37 Regulation of Plant Growth How Does Plant Development Proceed? What Do Gibberellins Do? What Does Auxin Do? What Do Cytokinins, Ethylene, Abscisic Acid, and Brassinosteroids Do? How Do Photoreceptors Participate in Plant Growth Regulation?
Background image of page 2
CPS 37.1 The vegetative parts of dicots that do not show secondary growth a. Have cell division in lateral meristems b. Have dormant apical meristems c. Have cell division only in apical meristems- shoot and root tips d. Have woody stems e. Die
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
37.1 How Does Plant Development Proceed? Four factors regulate plant growth: Environmental cues: light; day length Receptors such as photoreceptors Hormones The plant’s genomes
Background image of page 4
37.1 How Does Plant Development Proceed? Much recent progress in understanding plant growth and development has come from studies of Arabidopsis thaliana- green yeast It is used as a model organism—it is small, matures quickly , and its genomes have been fully sequenced. Mutants provide insights into mechanisms of hormones and receptors .
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
HOW PLANTS GROW Cell division takes place only in meristems , the plant equivalent of stem cells. Meristimatic tissue is undifferentiated. Meristems in non-woody plants are located at the tips (apical meristems) of the shoots and roots. Plants with wood and bark also contain lateral meristems and result in secondary growth. Cell expansion occurs by the uptake of water and maturation (differentiation) occurs after expansion.
Background image of page 6
37.1 How Does Plant Development Proceed? Hormones : regulatory chemicals that act at low concentrations at sites often quite distant from where they were produced. Each plant hormone is produced in many cells, and has multiple roles. … Interactions can be complex.
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Table 37.1 Plant Growth Hormones
Background image of page 8
37.1 How Does Plant Development Proceed? Photoreceptors are involved in many developmental processes. They are pigments associated with proteins. Light acts directly on photoreceptors, which in turn regulate development.
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
37.1 How Does Plant Development Proceed? Plants make use of signal transduction pathways —sequences of biochemical reactions by which a cell responds to a stimulus. Protein kinase cascades amplify responses to signals just as they do in other organisms.
Background image of page 10
37.1 How Does Plant Development Proceed? Seeds are dormant —the cells do not divide, expand, or differentiate. As the seed begins to germinate , it takes up water . The growing embryo obtains chemical building blocks by digesting the food stored in the seed. Germination is completed when the radicle (embryonic root) emerges. Now called a seedling .
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
If the seedling germinates underground, it must elongate rapidly, and cope with darkness for a time. A series of photoreceptors directs this
Background image of page 12
Image of page 13
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/22/2008 for the course BIOLOGY 020.152 taught by Professor Pearlman during the Spring '08 term at Johns Hopkins.

Page1 / 56

37 - 37 Regulation of Plant Growth 37 Regulation of Plant...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online