Seedless vascular plants reproduce via spores but, unlike non-vascular plants (hornworts, mosses, and liverworts) have a vascular system with xylem and phloem, which transport water and nutrients (Figure ). They do not produce flowers, fruits, or seeds. There are two major…
Non-vascular plants are a diverse group of plants with approximately 20,000 living species presenting a wide geographical distribution, ranging from tropical forests to high-latitude tundra, to high mountain ranges. They are the most ancient group of land plants, being the…
Before embarking on the exploration of the different groups of plants, let’s introduce the concept of alternation of generations in plant life cycles, which is inherited from the green algal ancestors of land plants. Alternation of generations means that plants…
All living organisms on Earth are divided into three domains (groups): Bacteria, Archaea, and Eukarya. Bacteria and Archaea are grouped in an informal category called prokaryotes, small unicellular organisms (smaller than the tip of a needle) that lack a nucleus…
Seeds are contained inside fruits. This is a good characteristic that you can use to differentiate between a fruit and another plant part. If it has seeds then it is a fruit (e.g. tomato, watermelon, pepper). If it does not…
A fruit is the swollen ovary of the flower, the last step in the process of sexual reproduction of flowering plants. After seeds are formed through fertilization, the tissue around those seeds starts to grow, forming the fruit. Fruits help…
The process of sexual reproduction in plants consists of several chronological steps: As with animals, for sexual reproduction to happen in plants the sperm needs to join the egg. The sperm of plants is contained in the pollen grains, therefore…
Angiosperms (flowering plants) are the only group of plants to produce flowers. Flowers are rather diverse, coming in different colors, sizes, and shapes (Figure ). Some have fragrances to attract pollinators and many offer pollen and nectar to reward the pollinator’s…
Leaves are the main site of photosynthesis. A typical leaf consists of a blade (the broad part of the leaf, also called the lamina) and a petiole (the stalk that attaches the leaf to a stem). The arrangement of leaves on a stem, known…
Learning Objective Identify common leaf modifications and their functions, including storage leaves, succulent leaves, spines, tendrils, phyllodes, showy bracts, plantlets, and insect traps. The structure and function of a leaf can be modified over the course of evolution as a…