When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Tracheid - Wikipedia

    en.wikipedia.org/wiki/Tracheid

    The fossil record shows three different types of tracheid cells found in early plants, which were classified as S-type, G-type and P-type. The first two of them were lignified and had pores to facilitate the transportation of water between cells. The P-type tracheid cells had pits similar to extant plant tracheids.

  3. Vascular plant - Wikipedia

    en.wikipedia.org/wiki/Vascular_plant

    Botanists define vascular plants by three primary characteristics: Vascular plants have vascular tissues which distribute resources through the plant. Two kinds of vascular tissue occur in plants: xylem and phloem. Phloem and xylem are closely associated with one another and are typically located immediately adjacent to each other in the plant.

  4. Vessel element - Wikipedia

    en.wikipedia.org/wiki/Vessel_element

    The presence of vessels in xylem has been considered to be one of the key innovations that led to the success of the flowering plants. It was once thought that vessel elements were an evolutionary innovation of flowering plants, but their absence from some basal angiosperms and their presence in some members of the Gnetales suggest that this hypothesis must be re-examined; vessel elements in ...

  5. Trachea - Wikipedia

    en.wikipedia.org/wiki/Trachea

    The trachea (pl.: tracheae or tracheas), also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all animals lungs. The trachea extends from the larynx and branches into the two primary bronchi.

  6. Endoderm - Wikipedia

    en.wikipedia.org/wiki/Endoderm

    the trachea, bronchi, and alveoli of the lungs: General: Endocrine glands and organs: the lining of the follicles of the thyroid gland and the epithelial component of the thymus (i.e. thymic epithelial cells). Auditory system: the epithelium of the auditory tube and tympanic cavity: Urinary system: the urinary bladder and part of the urethra

  7. Xylem - Wikipedia

    en.wikipedia.org/wiki/Xylem

    Different plant species can have different root pressures even in a similar environment; examples include up to 145 kPa in Vitis riparia but around zero in Celastrus orbiculatus. [ 13 ] The primary force that creates the capillary action movement of water upwards in plants is the adhesion between the water and the surface of the xylem conduits.

  8. Tracheole - Wikipedia

    en.wikipedia.org/wiki/Tracheole

    Tracheal system of the mite Stigmaeus humilis (C. L. Koch). Anthonie Cornelis Oudemans, 1913. Tracheole (trā'kē-ōl') is a fine respiratory tube of the trachea of an insect or a spider, part of the respiratory system. Tracheoles are about 1 μm in diameter, and they convey oxygen to cells while providing a means for carbon dioxide to escape.

  9. Organ system - Wikipedia

    en.wikipedia.org/wiki/Organ_system

    Plants have two major organs systems. Vascular plants have two distinct organ systems: a shoot system, and a root system. The shoot system consists stems, leaves, and the reproductive parts of the plant (flowers and fruits). The shoot system generally grows above ground, where it absorbs the light needed for photosynthesis. The root system ...