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In radial section, two tracheids of a coniferous wood species are shown. A series of bordered pits are also appearing in each tracheid. A tracheid of oak shows pits along the walls. It has no perforation plates. Angiosperms have both tracheids and vessel elements. [1] A tracheid is a long and tapered lignified cell in the xylem of vascular ...
Air enters the respiratory systems of insects through a series of external openings called spiracles. These external openings, which act as muscular valves in some insects, lead to the internal respiratory system, a densely networked array of tubes called tracheae. This network of transverse and longitudinal tracheae equalizes pressure ...
The tracheal system branches into progressively smaller tubes, here supplying the crop of the cockroach. Scale bar, 2 mm. The word trachea is used to define a very different organ in invertebrates than in vertebrates. Insects have an open respiratory system made up of spiracles, tracheae, and tracheoles to transport metabolic gases to and from ...
The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and plants. The anatomy and physiology that make this happen varies greatly, depending on the size of the organism, the environment in which it lives and its evolutionary ...
A bronchus (/ ˈ b r ɒ ŋ k ə s / BRONG-kəs; pl.: bronchi, / ˈ b r ɒ ŋ k aɪ / BRONG-ky) is a passage or airway in the lower respiratory tract that conducts air into the lungs.The first or primary bronchi to branch from the trachea at the carina are the right main bronchus and the left main bronchus.
In birds, some temperature control occurs in the respiratory system. [16] Water vapor heats cool air during inhalation in the trachea, and increases its humidity. [16] The resulting evaporative water loss varies greatly and depends on several factors including air sac pressure and the subsequent rate of air flow through the trachea.
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Upper respiratory system, with the nasopharynx, oropharynx and laryngopharynx labeled at left. The upper portion of the pharynx, the nasopharynx, extends from the base of the skull to the upper surface of the soft palate. [2] It includes the space between the internal nares and the soft palate and lies above the oral cavity.