What makes a plant? • Plants are unique because they make their own food by photosynthesis. Photosynthesis is a process of taking energy from the sun and using it to create sugars (food) that they use to grow. • Also, all plants have cell walls with cellulose and chlorophyll (makes it green). All plants have roots, leaves, and stems. However, all plants do not have flowers.
Plant Classification Plants are found on land, in oceans, and in fresh water. They have been on Earth for millions of years. Plants were on Earth before animals and currently number about 260,000 species. Three features distinguish plants from animals: (1)Plants have chlorophyll, a green pigment necessary for photosynthesis; (2)Their cell walls are made sturdy by a material called cellulose; and (3)They are fixed in one place (they don’t move).
Plants are classified in two ways:-The first way is Non-Vascular or Vascular. Non-Vascular Plants • This means the plants do not have true roots or stems, but are anchored in the ground by small, root like structures. They also have leaf-like structures to make their food, but the leaves are not true leaves because they do not have veins. Finally, these types of plants absorb nutrients and water from their surroundings. (So they are usually short ranging from a few millimeters to centimeters.)
Plants are classified in two ways:-The first way is Non-Vascular or Vascular. Vascular Plants • Vascular plants have tissue that supports the plants and carries water and food. Their roots, stems, and leaves all contain vascular tissue. The two types of vascular tissue are xylem (carries water and nutrients from roots to other parts of plant) and phloem (carries food from leaves to rest of plant). Vascular plants vary from angiosperms, to gymnosperms to deciduous to coniferous.
Plant ClassificationThe second way plants are classified is angiosperm or gymnosperm. • Plants are not only classified by non-vascular or vascular, they can also be classified by whether they produce flowers (angiosperm) or do not produce flowers (gymnosperm). • Finally, they can be further classified by angiosperms that are deciduous (lose leaves when fall comes) or gymnosperms that are coniferous (needles).
Gymnosperms • Gymnosperms have naked seeds. This means that their seeds are not protected by a seed coat. So reproduction is easy. A male pine cone becomes covered with pollen. Pollen contains sperm. Ovules grown on the female cones that contain eggs. Mature male cones release pollen grains. (Yellow Dust) Oh No…. Pollen season. The dust settled on the ovules of female cones. Sperm from the pollen fertilizes the eggs and seeds develop. When seeds are mature, the cone separates and releases the seed which have wings. The seed settles and a new gymnosperm begins to grow.
Gymnosperms Conifers Pine Tree • Most of the gymnosperms we see are coniferous. Conifers are a type of plant that have needles and cones. These types of gymnosperms do not lose their needles when the seasons change. They have a vascular system, but do not produce flowers. The other type of gymnosperms look like palm trees and are usually found in tropical regions.
Angiosperms • Angiosperms are plants that have seeds protected by a fruit. This makes it possible for them to live in all parts of the world. Reproduction is a little different than gymnosperms. When a fruit is in bloom, insects go to it and pollinate it. Sperm in the pollen fertilize the egg in the flower. The egg becomes a seed and the gets carried by wind or animals and begins to grow.
Plant Classification Angiosperms Images • These plants with flowers are the most developed of the plant species. They have advantages because they produce flowers. One advantage is the fruit/seed packaging, this encourages animals to help them reproduce. The other advantage is that the wind or animals allows them to grow in more areas because they spread their seeds further.