Transcript Developmental Biology 8/e

BIOL 370 – Developmental Biology
Topic #5
A Brief Overview of Plant Development
Lange
Please note that these PowerPoint lectures are based
upon material in the 8th edition of the Gilbert textbook.
The chapter is no longer included in more recent
editions of the textbook. However, as the topic is of
importance, we are covering aspects of it in our class.
As the 8th edition is no longer in print, the chapter
(labeled “Chapter 20” as it was referred to in the 8th
edition) can be found as a .pdf on our website if you
would like to read the chapter upon which this lecture
is based.
Plants have haplodiplontic life cycles that involve mitotic divisions in both the haploid and diploid
generations
Life cycle of an angiosperm, represented here by a pea plant (genus Pisum) (Part 1)
Life cycle of an angiosperm, represented here by a pea plant (genus Pisum) (Part 2)
(A) Pollen grains have intricate surface patterns (B) A pollen grain consists of a cell within a cell
The mature pollen-grain has a double wall, a thin delicate wall of
unaltered cellulose (the endospore or intine) and a tough outer
cuticularized exospore or exine. The exine often bears spines or warts, or
is variously sculptured, and the character of the markings is often of value
for identifying genus, species.
The carpel consists of the stigma, the style, and an ovary containing one or more ovules
The embryo sac is the product of three mitotic divisions of the haploid megaspore; it comprises
seven cells and eight haploid nuclei
Self-incompatibility
Calcium and pollen tube tip growth
Angiosperm embryogenesis (Part 1)
Angiosperm embryogenesis (Part 2)
End.