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Egyptian Slit-faced Bat
The Egyptian slit-faced bat (''Nycteris thebaica'') is a species of slit-faced bat broadly distributed throughout Africa and the Middle East. It is a species of microbat in the family Nycteridae. Six subspecies are known. Description The Egyptian slit-faced bat gets its name from a deep slit that runs from the base of the ears to the nostrils, between the nose leaves. The bats typically weigh , with females weighing up to . The wings are broad, with a wingspan of and a low aspect ratio, allowing for high maneuverability and the ability to hover close to the ground. The dorsal surface is dusky to reddish brown, while the underside is white to whitish gray. This bat has lighter fur than other members of the nycterid family. It has a long tail, reaching to . Distribution and habitat This species is able to thrive in a variety of tropical and temperate habitats throughout Africa and the Arabian Peninsula. A specimen of an Egyptian silt-faced bat was found on the island of Corf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. Other ways of defining species include their karyotype, DNA sequence, morphology (biology), morphology, behaviour, or ecological niche. In addition, palaeontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. About 14% of these had been described by 2011. All species (except viruses) are given a binomial nomenclature, two-part name, a "binomen". The first part of a binomen is the name of a genus to which the species belongs. The second part is called the specific name (zoology), specific name or the specific ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shrubland
Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominance (ecology), dominated by shrubs, often also including grasses, herbaceous plant, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It may be the mature vegetation type in a particular region and remain stable over time, or it may be a transitional community that occurs temporarily as the result of a disturbance, such as fire. A stable state may be maintained by regular natural disturbance such as fire or browsing (predation), browsing. Shrubland may be unsuitable for human habitation because of the danger of fire. The term was coined in 1903. Shrubland species generally show a wide range of adaptations to fire, such as heavy seed production, lignotubers, and fire-induced germination. Botanical structural form In botany and ecology a shrub is defined as a much-branched woody plant less than 8 m high, usually with many plant stem, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Large Slit-faced Bat
The large slit-faced bat (''Nycteris grandis'') is a species of slit-faced bat with a broad distribution in forest and savanna habitats in West, Central, and East Africa. ''N. marica'' (Kershaw, 1923), is the available name for the southern savanna species if it is recognized as distinct from this species. Description This bat is long and weighs less than (same for male and female). The name of this species comes from the furrow down its face. The furrow is partially covered by its nose-leaf. It has a reddish brown to gray fur on the back and upper areas. The torso is pale grey. Phylogeny The phylogeny of ''N. grandis'' is relatively unstable, but its closest relatives are ''N. hispida'' and ''N. aurita''. ''N. grandis'' can be easily distinguished by its size, as it is substantially larger than other members of the Nycteridae family. It has been suggested that there be a species subdivision established between ''N. grandis'' in Tanzania and Central Africa (''N. marica'') and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torpor
Torpor is a state of decreased physiological activity in an animal, usually marked by a reduced body temperature and metabolic rate. Torpor enables animals to survive periods of reduced food availability. The term "torpor" can refer to the time a hibernator spends at low body temperature, lasting days to weeks, or it can refer to a period of low body temperature and metabolism lasting less than 24 hours. The word comes from the early 13th century, originating from the Latin, ''torpor'', to be numb or sluggish. Animals that undergo torpor include birds (hummingbirds, notably strisores) and some mammals, including many marsupial species, rodent species (such as mice), and bats. During the active part of their day, such animals maintain normal body temperature and activity levels, but their metabolic rate and body temperature drop during a portion of the day (usually night) to conserve energy. Some animals seasonally go into long periods of inactivity, with reduced body temperat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hibernation
Hibernation is a state of minimal activity and metabolic reduction entered by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It is most commonly used to pass through winter months – called overwintering. Although traditionally reserved for "deep" hibernators such as rodents, the term has been redefined to include animals such as bears and is now applied based on active metabolic suppression rather than any absolute decline in body temperature. Many experts believe that the processes of daily torpor and hibernation form a continuum and use similar mechanisms. The equivalent during the summer months is aestivation. Hibernation functions to conserve energy when sufficient food is not available. To achieve this energy saving, an endothermic animal decreases its metabolic rate and thereby its body temperature. Hibernation may last days, weeks, or months—depending on t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterothermic
Heterothermy or heterothermia (from Greek ἕτερος ''heteros'' "other" and θέρμη ''thermē'' "heat") is a physiological term for animals that vary between self-regulating their body temperature, and allowing the surrounding environment to affect it. In other words, they exhibit characteristics of both poikilothermy and homeothermy. Definition Heterothermic animals are those that can switch between poikilothermic and homeothermic strategies. These changes in strategies typically occur on a daily basis or on an annual basis. More often than not, it is used as a way to dissociate the fluctuating metabolic rates seen in some small mammals and birds (e.g. bats and hummingbirds), from those of traditional cold blooded animals. In many bat species, body temperature and metabolic rate are elevated only during activity. When at rest, these animals reduce their metabolisms drastically, which results in their body temperature dropping to that of the surrounding environment. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gestation Period
In mammals, pregnancy is the period of reproduction during which a female carries one or more live offspring from implantation in the uterus through gestation. It begins when a fertilized zygote implants in the female's uterus, and ends once it leaves the uterus. Fertilization and implantation During copulation, the male inseminates the female. The spermatozoon fertilizes an ovum or various ova in the uterus or oviducts, and this results in one or multiple zygotes. Sometimes, a zygote can be created by humans outside of the animal's body in the artificial process of in-vitro fertilization. After fertilization, the newly formed zygote then begins to divide through mitosis, forming an embryo, which implants in the female's endometrium. At this time, the embryo usually consists of 50 cells. Development After implantation A blastocele is a small cavity on the center of the embryo, and the developing embryonary cells will grow around it. Then, a flat layer cell forms on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythrocytes
Red blood cells (RBCs), referred to as erythrocytes (, with -''cyte'' translated as 'cell' in modern usage) in academia and medical publishing, also known as red cells, erythroid cells, and rarely haematids, are the most common type of blood cell and the vertebrate's principal means of delivering oxygen () to the body tissue (biology), tissues—via blood flow through the circulatory system. Erythrocytes take up oxygen in the lungs, or in fish the gills, and release it into tissues while squeezing through the body's capillary, capillaries. The cytoplasm of a red blood cell is rich in hemoglobin (Hb), an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million hemoglobin molecules. The cell membrane is composed of proteins and lipids, and this structure provides properties essential for physiological Cell (biology), cell function such as erythrocyte deformabil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endocytosis
Endocytosis is a cellular process in which Chemical substance, substances are brought into the cell. The material to be internalized is surrounded by an area of cell membrane, which then buds off inside the cell to form a Vesicle (biology and chemistry), vesicle containing the ingested materials. Endocytosis includes pinocytosis (cell drinking) and phagocytosis (cell eating). It is a form of active transport. History The term was proposed by Christian de Duve, De Duve in 1963. Phagocytosis was discovered by Élie Metchnikoff in 1882. Pathways Endocytosis pathways can be subdivided into four categories: namely, receptor-mediated endocytosis (also known as clathrin-mediated endocytosis), caveolae, pinocytosis, and phagocytosis. * Clathrin-mediated endocytosis is mediated by the production of small (approx. 100 nm in diameter) vesicles that have a morphologically characteristic coat made up of the cytosolic protein clathrin. Clathrin-coated vesicles (CCVs) are found in vir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placenta
The placenta (: placentas or placentae) is a temporary embryonic and later fetal organ that begins developing from the blastocyst shortly after implantation. It plays critical roles in facilitating nutrient, gas, and waste exchange between the physically separate maternal and fetal circulations, and is an important endocrine organ, producing hormones that regulate both maternal and fetal physiology during pregnancy. The placenta connects to the fetus via the umbilical cord, and on the opposite aspect to the maternal uterus in a species-dependent manner. In humans, a thin layer of maternal decidual ( endometrial) tissue comes away with the placenta when it is expelled from the uterus following birth (sometimes incorrectly referred to as the 'maternal part' of the placenta). Placentas are a defining characteristic of placental mammals, but are also found in marsupials and some non-mammals with varying levels of development. Mammalian placentas probably first evolved abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uterus Duplex
A uterine malformation is a type of female genital malformation resulting from an abnormal development of the Müllerian duct(s) during embryogenesis. Symptoms range from amenorrhea, infertility, recurrent pregnancy loss, and pain, to normal functioning depending on the nature of the defect. Types The American Fertility Society (now American Society of Reproductive Medicine) Classification distinguishes: ; Class I—Müllerian agenesis (absent uterus). : This condition is represented by the hypoplasia or the agenesis (total absence) of the different parts of the uterus: :* Vaginal hypoplasia or agenesis :* Cervical hypoplasia or agenesis :* Fundal hypoplasia or agenesis (absence or hypoplasia of the fundus of the uterus) :* Tubal hypoplasia or agenesis (absence or hypoplasia of the fallopian tubes) :* Combined hypoplasia the agenesis of different part of the uterus :This condition is also called Mayer-Rokitansky-Kuster-Hauser syndrome. The patient with MRKH syndrome will ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaginal Canal
In mammals and other animals, the vagina (: vaginas or vaginae) is the elastic, muscular reproductive organ of the female genital tract. In humans, it extends from the vulval vestibule to the cervix (neck of the uterus). The vaginal introitus is normally partly covered by a thin layer of mucosal tissue called the hymen. The vagina allows for copulation and birth. It also channels menstrual flow, which occurs in humans and closely related primates as part of the menstrual cycle. To accommodate smoother penetration of the vagina during sexual intercourse or other sexual activity, vaginal moisture increases during sexual arousal in human females and other female mammals. This increase in moisture provides vaginal lubrication, which reduces friction. The texture of the vaginal walls creates friction for the penis during sexual intercourse and stimulates it toward ejaculation, enabling fertilization. Along with pleasure and bonding, women's sexual behavior with other people c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
