Endocrine disruptorEndocrine disruptors, sometimes also referred to as hormonally active agents, endocrine disrupting chemicals, or endocrine disrupting compounds are chemicals that can interfere with endocrine (or hormonal) systems. These disruptions can cause cancerous tumors, birth defects, and other developmental disorders. Found in many household and industrial products, endocrine disruptors "interfere with the synthesis, secretion, transport, binding, action, or elimination of natural hormones in the body that are responsible for development, behavior, fertility, and maintenance of homeostasis (normal cell metabolism).
Adrenal cortexThe adrenal cortex is the outer region and also the largest part of an adrenal gland. It is divided into three separate zones: zona glomerulosa, zona fasciculata and zona reticularis. Each zone is responsible for producing specific hormones. It is also a secondary site of androgen synthesis. The adrenal cortex comprises three main zones, or layers that are regulated by distinct hormones as noted below. This anatomic zonation can be appreciated at the microscopic level, where each zone can be recognized and distinguished from one another based on structural and anatomic characteristics.
Hybrid (biology)In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a chimera. Hybrids are not always intermediates between their parents (such as in blending inheritance), but can show hybrid vigor, sometimes growing larger or taller than either parent.
Androgen deficiencyAndrogen deficiency is a medical condition characterized by insufficient androgenic activity in the body. Androgenic activity is mediated by androgens (a class of steroid hormones with varying affinities for the androgen receptor), and is dependent on various factors including androgen receptor abundance, sensitivity and function. Symptoms of the condition in males consist of loss of libido, impotence, infertility, shrinkage of the testicles, penis, and prostate, diminished masculinization (e.g.
Androgen insensitivity syndromeAndrogen insensitivity syndrome (AIS) is a difference in sex development involving hormonal resistance due to androgen receptor dysfunction. It affects 1 in 20,000 to 64,000 XY (karyotypically male) births. The condition results in the partial or complete inability of cells to respond to androgens. This unresponsiveness can impair or prevent the development of male genitals, as well as impairing or preventing the development of male secondary sexual characteristics at puberty.
Bird vocalizationBird vocalization includes both bird calls and bird songs. In non-technical use, bird songs are the bird sounds that are melodious to the human ear. In ornithology and birding, songs (relatively complex vocalizations) are distinguished by function from calls (relatively simple vocalizations). The distinction between songs and calls is based upon complexity, length, and context. Songs are longer and more complex and are associated with territory and courtship and mating, while calls tend to serve such functions as alarms or keeping members of a flock in contact.
GnathostomataGnathostomata (ˌnæθoʊ-'stɒmətə; from Greek: γνάθος (gnathos) "jaw" + στόμα (stoma) "mouth") are the jawed vertebrates. Gnathostome diversity comprises roughly 60,000 species, which accounts for 99% of all living vertebrates, including humans. In addition to opposing jaws, living gnathostomes have true teeth (a characteristic which has subsequently been lost in some), paired appendages (pectoral and pelvic fins, arms, legs, wings, etc.
Partial androgen insensitivity syndromePartial androgen insensitivity syndrome (PAIS) is a condition that results in the partial inability of the cell to respond to androgens. It is an X linked recessive condition. The partial unresponsiveness of the cell to the presence of androgenic hormones impairs the masculinization of male genitalia in the developing fetus, as well as the development of male secondary sexual characteristics at puberty, but does not significantly impair female genital or sexual development.
Animal communicationAnimal communication is the transfer of information from one or a group of animals (sender or senders) to one or more other animals (receiver or receivers) that affects the current or future behavior of the receivers. Information may be sent intentionally, as in a courtship display, or unintentionally, as in the transfer of scent from predator to prey with kairomones. Information may be transferred to an "audience" of several receivers. Animal communication is a rapidly growing area of study in disciplines including animal behavior, sociology, neurology and animal cognition.
AgnathaAgnatha ('ægnəθə,_æg'neɪθə; ) is an infraphylum of jawless fish in the phylum Chordata, subphylum Vertebrata, consisting of both present (cyclostomes) and extinct (conodonts and ostracoderms) species. Among recent animals, cyclostomes are sister to all vertebrates with jaws, known as gnathostomes. Recent molecular data, both from rRNA and from mtDNA as well as embryological data, strongly supports the hypothesis that living agnathans, the cyclostomes, are monophyletic.
