Air Sacs
Thin-walled sacs or spaces which function as a part of the respiratory system in birds, fishes, insects, and mammals.
Air
Yolk Sac
The first of four extra-embryonic membranes to form during EMBRYOGENESIS. In REPTILES and BIRDS, it arises from endoderm and mesoderm to incorporate the EGG YOLK into the DIGESTIVE TRACT for nourishing the embryo. In placental MAMMALS, its nutritional function is vestigial; however, it is the source of INTESTINAL MUCOSA; BLOOD CELLS; and GERM CELLS. It is sometimes called the vitelline sac, which should not be confused with the VITELLINE MEMBRANE of the egg.
Reindeer
A genus of deer, Rangifer, that inhabits the northern parts of Europe, Asia, and America. Caribou is the North American name; reindeer, the European. They are often domesticated and used, especially in Lapland, for drawing sleds and as a source of food. Rangifer is the only genus of the deer family in which both sexes are antlered. Most caribou inhabit arctic tundra and surrounding arboreal coniferous forests and most have seasonal shifts in migration. They are hunted extensively for their meat, skin, antlers, and other parts. (From Webster, 3d ed; Walker's Mammals of the World, 5th ed, p1397)
Larynx
A tubular organ of VOICE production. It is located in the anterior neck, superior to the TRACHEA and inferior to the tongue and HYOID BONE.
Dinosaurs
Air Pollutants
Any substance in the air which could, if present in high enough concentration, harm humans, animals, vegetation or material. Substances include GASES; PARTICULATE MATTER; and volatile ORGANIC CHEMICALS.
Air Pollution
The presence of contaminants or pollutant substances in the air (AIR POLLUTANTS) that interfere with human health or welfare, or produce other harmful environmental effects. The substances may include GASES; PARTICULATE MATTER; or volatile ORGANIC CHEMICALS.
Poultry Diseases
Diseases of birds which are raised as a source of meat or eggs for human consumption and are usually found in barnyards, hatcheries, etc. The concept is differentiated from BIRD DISEASES which is for diseases of birds not considered poultry and usually found in zoos, parks, and the wild.
Endolymphatic Sac
Neck Muscles
The neck muscles consist of the platysma, splenius cervicis, sternocleidomastoid(eus), longus colli, the anterior, medius, and posterior scalenes, digastric(us), stylohyoid(eus), mylohyoid(eus), geniohyoid(eus), sternohyoid(eus), omohyoid(eus), sternothyroid(eus), and thyrohyoid(eus).
Respiratory System
The tubular and cavernous organs and structures, by means of which pulmonary ventilation and gas exchange between ambient air and the blood are brought about.
Thorax
Anal Sacs
Turkeys
Embolism, Air
Blocking of a blood vessel by air bubbles that enter the circulatory system, usually after TRAUMA; surgical procedures, or changes in atmospheric pressure.
Air Microbiology
The presence of bacteria, viruses, and fungi in the air. This term is not restricted to pathogenic organisms.
Finches
Common name for small PASSERIFORMES in the family Fringillidae. They have a short stout bill (BEAK) adapted for crushing SEEDS. Some species of Old World finches are called CANARIES.
Songbirds
PASSERIFORMES of the suborder, Oscines, in which the flexor tendons of the toes are separate, and the lower syrinx has 4 to 9 pairs of tensor muscles inserted at both ends of the tracheal half rings. They include many commonly recognized birds such as CROWS; FINCHES; robins; SPARROWS; and SWALLOWS.
Diving
Poultry
Domesticated birds raised for food. It typically includes CHICKENS; TURKEYS, DUCKS; GEESE; and others.
Trachea
The cartilaginous and membranous tube descending from the larynx and branching into the right and left main bronchi.
Acoustic Impedance Tests
Objective tests of middle ear function based on the difficulty (impedance) or ease (admittance) of sound flow through the middle ear. These include static impedance and dynamic impedance (i.e., tympanometry and impedance tests in conjunction with intra-aural muscle reflex elicitation). This term is used also for various components of impedance and admittance (e.g., compliance, conductance, reactance, resistance, susceptance).