Structures of flowering plants are well-adapted to varied environments, including water.
The body of a vascular plant is organized into two general kinds of organs: a Root System (the roots) and a Shoot System (the stems and leaves) . These organs all contain tissue systems, but they differ in the way the cells are specialized to carry out different functions.
Roots, stems, and leaves are the vegetative organs of plants; flowers, seeds, and fruits are reproductive structures.
Root System
A plant's root system is underground.The root system is primary root plus the branch roots.
It is generally equal in the size of the shoot systems, the part above ground.
Root systems have the following functions:
- Roots anchor a plant in soil and give support.
- Roots absorb water and minerals from soil, root hairs are central to this process.
* Root hairs are numerous to increase the absorptive surface of a root.
* Transplanting plants damages a plant when the root hairs are torn off.
* Water and nutrients absorbed are distributed to the plant.
* Roots produce hormones the must be distributed to the plant.
Perennials "Die Back" to regrow the next season; root of herbaceous perennials store food (carrots, sweet potatoes)
Shoot System
The shoot system is above ground and includes the organs such as leaves, stems, and the branches.
Stems
1. The stem forms the main axis of the plant, along with lateral branches.
2. Upright stems produce leaves and array them to be exposed to as much as possible.
3. A node occurs where a leaf attaches to the stem and an internode is the region between nodes; nodes and internodes identify a stem even if it is underground.
4. The stem has a vascular tissue to transport water and minerals from the roots and the sugar form leaves.
5. Nonliving cells from a continuous pipeline through vascular tissue.
6. A cylindrical stem expands in girth and length; trees use woody tissues to strengthen stems.
7. Stems may function in storage : cactus stems store water and tubers are horizontal stems that store nutrients.
Leaves
1. A leaf is the major organ of photosynthesis in most plants.
2. Leaves receive water from roots by way of the stem.
3. Broad, thin leaves have a maximum surface area to absorb CO2 and collect solar energy.
4. A blade is the wide portion of a leaf with the most photosynthetic tissues.
5. The petiole is a stalk that attaches a leaf blade to the stem.
6. the leaf axil is the upper acute angle between petiole and stem where an axillary (lateral) bud originates.
7. Some leaves protect buds, attach to objects (tendrils), store food (bulbs), or capture insects.
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Questions:
1. Name the two general kinds of organs of a plant?
2. Name one function of the following : Root - Leaves - Stems
3. What is Perennial ?
4. Why the stem has a a vascular tissue?
Stems
1. The stem forms the main axis of the plant, along with lateral branches.
2. Upright stems produce leaves and array them to be exposed to as much as possible.
3. A node occurs where a leaf attaches to the stem and an internode is the region between nodes; nodes and internodes identify a stem even if it is underground.
4. The stem has a vascular tissue to transport water and minerals from the roots and the sugar form leaves.
5. Nonliving cells from a continuous pipeline through vascular tissue.
6. A cylindrical stem expands in girth and length; trees use woody tissues to strengthen stems.
7. Stems may function in storage : cactus stems store water and tubers are horizontal stems that store nutrients.
Leaves
1. A leaf is the major organ of photosynthesis in most plants.
2. Leaves receive water from roots by way of the stem.
3. Broad, thin leaves have a maximum surface area to absorb CO2 and collect solar energy.
4. A blade is the wide portion of a leaf with the most photosynthetic tissues.
5. The petiole is a stalk that attaches a leaf blade to the stem.
6. the leaf axil is the upper acute angle between petiole and stem where an axillary (lateral) bud originates.
7. Some leaves protect buds, attach to objects (tendrils), store food (bulbs), or capture insects.
-=-=-=-=-=-=-=-=-=-=-
Questions:
1. Name the two general kinds of organs of a plant?
2. Name one function of the following : Root - Leaves - Stems
3. What is Perennial ?
4. Why the stem has a a vascular tissue?
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