The Plant Kingdom The oldest and most simple photosynthetic organisms on earth are algae. The multicellular algae are separated into divisions based on their photosynthetic pigments, food storage products, and cell-wall components. The three major groups include: Brown algae Red algae Green algae
The Plant Kingdom
Non-Vascular Moss
Non-Vascular Liverwort Hornwort
The Plant Kingdom
The Plant Kingdom – structure of a leaf 1. Xylem – responsible for moving water and minerals from roots to shoots 2. Phloem – carries substances synthesized by the plant, including sugars, amino acids, and hormones.
The Plant Kingdom – Vascular system The vascular tissue system is responsible for transport of water, minerals, sugars, and plant hormones. There are primarily two types of vascular tissues found in plants: 1. Xylem – responsible for moving water and minerals from roots to shoots. Typically they make up of non-living tissue… 2. Phloem – carries substances synthesized by the plant, including sugars, amino acids, and hormones. Phloem cells are however all living… why? Note that this system is continuous throughout the plant, from the roots all the way to the smallest of the leaves…
The Plant Kingdom – Reproduction Alternation of Generations
The Plant Kingdom – Reproduction Bryophytes:
The Plant Kingdom – Reproduction Ferns:
The Plant Kingdom – Reproduction Gymnosperms:
The Plant Kingdom – Angiosperm Reproduction
The Plant Kingdom – Angiosperm Reproduction
The Plant Kingdom – Angiosperm Reproduction
The Plant Kingdom – Angiosperm Reproduction
The Plant Kingdom – Angiosperm Reproduction So why are angiosperms so successful?
The Plant Kingdom How do plants defend themselves against herbivores? Mechanical defenses: Waxy cuticle – prevents bacterial and fungal growth Hairy or sticky leaves – discourage caterpillars and other tiny herbivores Spines, thorns, and prickles – fend off larger mammalian herbivores Chemical defenses: Thousands of different compounds are produced and used by plants. Some of these chemicals include some of the most powerful drugs known to humans (e.g. caffeine, nicotine, cocaine, morphine, etc.)
The Plant Kingdom Review of some major concepts in plants: Plants are multicellular, photosynthetic eukaryotes. Plants evolved from a green algal ancestor All plants alternate between sporophyte and gametophyte generations Major trends in evolution of the plant kingdom * growing independence from liquid water * increasing size and independence of the sporophyte generation Non-vascular plants include mosses and liverworths… they lack true leaves and roots… why? Xylem is a vascular tissue for conducting water and minerals; phloem is a vascular tissue for conducting foods. Gymnosperms and angiosperms possess seeds; ferns do not Non-vascular plants and ferns depend on liquid water for fertilization
The Plant Kingdom Review of some major concepts in plants (cont.): The pollen of seed plants has evolved mechanisms for dispersal, so liquid water is not needed for the transfer of male gametes. Gymnosperms have a life cycle in which naked seeds are produced on the scales of cones Angiosperms are distinguished by the production of flowers and fruits.