Pecten (biology)

Pectines are comb-like structures, widely found in the biological world. They occur, for example, on the underside of scorpions, where they are used as sense organs. In ducks they are placed on the sides of the bill and serve both as food-strainer and as a comb for preening. The avian eye also contains a structure called a pecten oculi, which is a comb-like projection of the retina. It is thought to enhance nutrition for the cells of the retina. Whales have a similar comb-like structure called baleen.

"Pectinate" means supplied with a comb-like structure and is reflected in numerous specific names as "pectinata", "pectinatus" or "pectinatum", or in specific epithets e.g. Murex pecten.

Biology

Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, evolution, distribution, and taxonomy. Modern biology is a vast and eclectic field, composed of many branches and subdisciplines. However, despite the broad scope of biology, there are certain general and unifying concepts within it that govern all study and research, consolidating it into single, coherent fields. In general, biology recognizes the cell as the basic unit of life, genes as the basic unit of heredity, and evolution as the engine that propels the synthesis and creation of new species. It is also understood today that all organisms survive by consuming and transforming energy and by regulating their internal environment to maintain a stable and vital condition.

Subdisciplines of biology are defined by the scale at which organisms are studied, the kinds of organisms studied, and the methods used to study them: biochemistry examines the rudimentary chemistry of life; molecular biology studies the complex interactions among biological molecules; botany studies the biology of plants; cellular biology examines the basic building-block of all life, the cell; physiology examines the physical and chemical functions of tissues, organs, and organ systems of an organism; evolutionary biology examines the processes that produced the diversity of life; and ecology examines how organisms interact in their environment.

Biology (journal)

Biology is a quarterly, peer-reviewed, open access, scientific journal covering research on all aspects of biology. It was established in 2012 and is published by MDPI. The editor-in-chief is Chris O'Callaghan (University of Oxford). The journal publishes reviews, research papers, and communications.

Subject Areas

This journal covers all topics related to biology. More detail about the journal and its scope is available in the first editorial. Research fields of interest include, but are not limited to:

Biology: The Unity and Diversity of Life

Biology: The Unity and Diversity of Life is a college-level introductory biology textbook that covers basic biochemistry, anatomy, taxonomy, evolution, biotechnology and ecology. The book is designed to create in students a broad foundation of knowledge in biology and is frequently used in AP Biology classes in American high schools. Each book includes an interactive CD-ROM with links to additional instructional material. Like many textbooks new versions are printed every few years and reflect new gains in scientific knowledge. The book is published by Brooks/Cole and is currently in its twelfth edition. It was primarily compiled by Cecie Starr and Ralph Taggart with pictures and illustrations by Lisa Starr.

The book was translated into few languages, among others into Hebrew, published by the Open University of Israel.

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Pecten

Pecten may refer to:

See also

Pecten oculi

The pecten or pecten oculi is a comb-like structure of blood vessels belonging to the choroid in the eye of a bird. It is a non-sensory, pigmented structure that projects into the vitreous body from the point where the optic nerve enters the eyeball. The pecten is believed to both nourish the retina and control the pH of the vitreous body. High level of enzyme alkaline phosphatase activity in pecten oculi, has been linked to transport of nutrient molecules from highly vascularized pecten oculi into vitreous and then into retinal cells for nourishment. It is present in all birds and some reptiles.

In the vertebrate eye, blood vessels lie in front of the retina, partially obscuring the image. The pecten helps to solve this problem by greatly reducing the number of blood vessels in the retina and leading to the extremely sharp eyesight of birds such as hawks. The pigmentation of the pecten is believed to protect the blood vessels against damage from ultraviolet light. Stray-light absorption by melanin granules of pecten oculi is also considered to give rise to small increments in temperature of pecten and eye; this may offer increased metabolic rate to optimize eye physiology in low temperatures at high-altitude flights. The structure varies across bird species and is conical in the kiwi, vaned in the ostrich and pleated in most other birds.

Pecten (genus)

Pecten is a genus of large scallops or saltwater clams, marine bivalve mollusks in the family Pectinidae, the scallops. This is the type genus of the family.

This genus is known in the fossil record from the Cretaceous period to the Quaternary period (age range: from 70.6 to 0.012 million years ago.). Fossil shells within this genus have been found all over the world.

Etymology

The name Pecten is from the Latin word for a comb or rake. Since 1904, a Pecten shell has been used as the basis of the logo of Shell petroleum company.

Species

Species in the genus Pecten include: