Presentation on theme: "Dr. Najat Abdulwahab Bukhari Lecture 12. University Vision and Mission Vision: To be a world-class university and a leader in developing Saudi Arabias."— Presentation transcript:
Dr. Najat Abdulwahab Bukhari Lecture 12
University Vision and Mission Vision: To be a world-class university and a leader in developing Saudi Arabias knowledge economy Mission: To provide students with a quality education, conduct valuable research, serve the national and international societies and contribute to Saudi Arabias knowledge economy through learning, creativity, the use of current and developing technologies and effective international partnership.
Vision: upgrading the academic and research to keep pace with scientific progress and requirements of society. Mission: Development of Academic process and develop scientific research through strategic planning and a clear vision for science and technology at the country level. As well as training of national cadres, and the introduction of a methodology developed to meet the different needs of society, and to serve the various research and developmental projects in the community Botany department Vision and Mission
Course Description Topics to be Covered TopicNo of Weeks Contact hours - Historical review of plant taxonomy (industrial, natural, evolution) 12 - Nomenclature12 - Classic taxonomy (morphological taxonomy of vegetation and floral characters – Fruits and seed characters Key to taxonomical unites.12 - Fertilization and seed formation22 - The different kinds of fruits22 - The sexual differentiations of flowers and their fertilization 22 14
Floral formula Floral formula is a summary of the structure and components of a flower using symbols and numbers. The parts of the flower are represented by: K (for calyx) C (for corolla) P (for perianth) A (for androecium) G (for gynoecium) The symbol G has a line above it to indicate an inferior ovary and a line beneath it to indicate a superior ovary
The sexuality of the flower is represented by the standard symbols for males () and females (). Bisexual The symbols representing symmetry include: ygomrphic Actinomorphic Zygomorphic "M" for a monoecious system and "D" when dioecious. (PM) polygamomonoecious (PD)polygamodioecious
indicates an indefinite number of parts (more than 12). ( ) If the parts are fused. ….+…. if they are in separate groups * = staminode; a sterile stamen = ovary inferior to insertion point of the other whorls. G = ovary superior to insertion point of other floral whorls = ovary inferior to superior - variation exists
The structure of a flower is composed by the previous floral formula and appropriate symbols and the placentation type within the ovary. Any descriptive terms can be added to describe an important floral character such as the sub- calex or sterile stamens, etc......
How to dissect a flower Using the above rules we can follow these steps and the observations: Floral Diagram: Floral diagram is the stylized cross sections of flowers that represent the floral whorls as viewed from above, showing the arrangement and number of parts in a flower, ovary is drawn as a cercal in the centre. Posterior side Peduncle.
In the case of florets the focus is to the large flower (axis of the rest of the flowers). If exists the bract is drawn at the bottom of the paint, to the Anterior side of the flower. The floral whorls represented by circles.
Longitudinal Section 1- parts of flower drawn by order of parts on the pedicles. 2- taking in consecration the ratio of the lengths of these parts maintaining the proportions of the real lengths.
Positions of sepals and petals do not represent the sector in the longitudinal and represent only the full parts and the fusion places of docking between the parts to each other while maintaining the ratio The longitudinal sector shows the stamens position. Whether its out of pedicel or. And shows the various shapes of calyx.
Floral Diagram Symbols II
Sample floral diagrams
Sample Floral Diagrams Described
Distribution of sex in flowers Poly sexual Mult sexual Poly gamy Multi sexual flowers, male and female flowers Bi sexual Dio gamy Some flowers formed having stamens and pistils : Mono sexual Mono gamay Mixed pollination Allo gamy
Mono sexual Mono gamy 2- Dioecious Having the male and female organs in separate and distinct individuals; having separate sexes Phoenix dactylifera 1- Monoecious Having separate male flowers and female flowers on the same plant, as in corn Zea mays
Bi sexual 2- Dichogam the condition of having stamens and pistils mature at different times Allo gamy followed with Auto gamy 1- Homogamy the condition of having stamens and pistils mature at the same time Two situations:
Homogamy Cleisto gamy Failure of a flower to open, stamens and styles mature self pollination. Chasmo gamy A flower which is chasmogamous opens and exposes the stamens and styles.
Dichogam Protogamy Stamens mature before styles. As in strawberry. Protandry Styles mature before stamens. Compound family