Plant

• A plant has three vegetative parts: the leaf, stem and roots
• The leaf is the main photosynthetic organ
• The stem can also do photosynthesis because it contains chloroplasts, but its main function is to elongate the plant to maximize photosynthesis
• The roots absorbs minerals, water, and often stores carbohydrates and other reserves
• There are two kinds of plants: With flower (monocots & dicots) and No flower (moss and ferns)
• Parenchyma, collenchyma, and sclerenchyma cells are considered as simple plant cells. While, Xylem and Phloem are considered complex plant cells.
• The difference between sclerenchyma and collenchyma is that sclerenchyma is tough and collenchyma is flexible. And upon maturity (reaching the max height), sclerenchyma cells die while collenchyma still lives
• Xylem cells conduct water and die upon maturity. They contain tracheids which conducts water through pits and they have a smaller diameter compared to vessel elements. Vessel elements conducts water AND minerals through pits and perforated end walls.
• Phloem cells conduct food & nutrients. They contain sieve tubes which conduct dissolved sugars and other organic compounds while companion cells transfer materials into and out of sieve tube elements
• There are 2 types of plant tissues: Meristematic and permanent. Meristematic tissues are consisted of undifferentiated cells (young cells) that are capable of cellular division. While Permanent tissues are tissues that lost the ability to divide. They also exist with the same appearance until old age.
• There are 2 types of permanent tissue: simple and complex (uses the simple & complex plant cells). These tissues are the components of ground (simple permanent), vascular (complex permanent), and dermal (simple permanent) tissues.
• Ground tissues includes cells specialized for functions such as storage (parenchyma), photosynthesis (parenchyma), support, short-distance transport, and metabolic processes.
• Dermal tissues are the plant's outer covering. In non-woody plants, it is usually a single tissue called the epidermis, a layer of tightly packed cells that secretes fatty substances and are transparent parenchyma cells. In leaves and most stems, the cuticle, a waxy epidermal coating, helps prevent water loss. The pores in the cuticle are called stomata which help exchange gases between the atmosphere and the plant. Guard cells open and close the stomata.
• Vascular tissues facilitate the transport of materials through the plant and to provide mechanical support.
• Plant growth occurs at meristems
• Meristematic tissues help in the production of new cells (through cellular division) and are actively dividing to increase its length & diameter.
• The apical meristem increases the length of plants and this is in the form of primary growth (vertical growth). It is found in the tips of stems and roots
• The intercallary meristem increases branches and leaves through primary growth (vertical growth). And it is found in the base of leaves and internodes
• The lateral meristem increases the diameter of plants and this is called secondary growth (horizontal/width growth) It is found in the sides of stems and roots.
• Plastids sotres glucoses via photosynthesis.