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A similar, but more directed version of kinesis is taxis    : the directed movement towards or away from a stimulus. This movement can be in response to light (phototaxis), chemical signals (chemotaxis), or gravity (geotaxis) and can be directed toward (positive) or away (negative) from the source of the stimulus. An example of a positive chemotaxis is exhibited by the unicellular protozoan Tetrahymena thermophila . This organism swims using its cilia, at times moving in a straight line, and at other times making turns. The attracting chemotactic agent alters the frequency of turning as the organism moves directly toward the source, following the increasing concentration gradient.

Fixed action patterns

A fixed action pattern    is a series of movements elicited by a stimulus such that even when the stimulus is removed, the pattern goes on to completion. An example of such a behavior occurs in the three-spined stickleback, a small freshwater fish ( [link] ). Males of this species develop a red belly during breeding season and show instinctual aggressiveness to other males during this time. In laboratory experiments, researchers exposed such fish to objects that in no way resemble a fish in their shape, but which were painted red on their lower halves. The male sticklebacks responded aggressively to the objects just as if they were real male sticklebacks.

Photo shows a white fish with a reddish bottom on top. Below the fish is a diamond-shaped object that resembles a fishing lure; it is white on the top and red on the bottom, with an eye at the front.
Male three-spined stickleback fish exhibit a fixed action pattern. During mating season, the males, which develop a bright red belly, react strongly to red-bottomed objects that in no way resemble fish.

Migration

Migration is the long-range seasonal movement of animals. It is an evolved, adapted response to variation in resource availability, and it is a common phenomenon found in all major groups of animals. Birds fly south for the winter to get to warmer climates with sufficient food, and salmon migrate to their spawning grounds. The popular 2005 documentary March of the Penguins followed the 62-mile migration of emperor penguins through Antarctica to bring food back to their breeding site and to their young. Wildebeests ( [link] ) migrate over 1800 miles each year in search of new grasslands.

Photo shows a heard of wildebeests crossing a river.
Wildebeests migrate in a clockwise fashion over 1800 miles each year in search of rain-ripened grass. (credit: Eric Inafuku)

Although migration is thought of as innate behavior, only some migrating species always migrate (obligate migration). Animals that exhibit facultative migration can choose to migrate or not. Additionally, in some animals, only a portion of the population migrates, whereas the rest does not migrate (incomplete migration). For example, owls that live in the tundra may migrate in years when their food source, small rodents, is relatively scarce, but not migrate during the years when rodents are plentiful.

Foraging

Foraging is the act of searching for and exploiting food resources. Feeding behaviors that maximize energy gain and minimize energy expenditure are called optimal foraging behaviors, and these are favored by natural section. The painted stork, for example, uses its long beak to search the bottom of a freshwater marshland for crabs and other food ( [link] ).

Questions & Answers

Oh, how's is it going..
Brian Reply
not too good
Monique
hy
Adeola
hi
Imamkasim
hi
Veronica
Any one else taking Bio 1406 with Stephanie Martin?
Veronica
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iyota
Part of compound microscope
Bakish Reply
a. body b. stage clip c. adjacent knob d. arm e. eye piece
Kpodo
How do u know when you want to urinate
Akpo Reply
how do you know when you want to urinate
Akpo
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Coded
As the bladder fills up .. the signals are sent to the brain specifying that its filling up and should be emptied and the fuller it gets, the more signals/ alerts are sent to brain ...leading to the urge to urinate .... to go pee
Khalida
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Coded
hello
Issiya
hi
Abigail
I want the this ecologycal terms
Catherine Reply
what are enzymes
Alvin Reply
enzymes are organic catalysts which speed the rate of chemical reaction but it's self is not used up in the process
Azeezah
what is fertilization
Ofosu Reply
fusion of male and famele gametes
Biology
fusion of female and male gametes.
Biology
form zygote to eggs
Ahmad
also known as syngamy
RESHMA
why is water called a polar molecule
Jabari Reply
enzyme that not found in mitochondria
Mukesh Reply
Internal carotid arteries
Anjola Reply
A closed circulatory system is a closed-loop system, in which blood is not free in a cavity. Blood is separate from the bodily interstitial fluid and contained within blood vessels. In this type of system, blood circulates unidirectionally from the heart around the systemic circulatory route, and th
Peter Reply
food
Ramatulai
Is DNA a proteins or genetic materials ?
Bisallah
what is meiosis
Ram Reply
meiosis is a reduction Division in which four hapliod off springs are produced
Nandanee
what is electrochemical gradient?
Joneth Reply
what is mitosis?
Aliness Reply
(cytology) the division of cell nucleus in which the genome is copied and separated into two identical halves.it is normally follow by cell division
Adekunle
it Is the division of the mother cell into two daughter cells,genetically identical to each other and to their parent cell
Joneth
it is a study of living organisms
Prudence Reply
What are other types of cell
ATAMA Reply
plant and animal cell
Jessy
prokaryotic and eukaryotic cell
Joneth
meaning inside and outside cells
Joneth

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Source:  OpenStax, Biology. OpenStax CNX. Feb 29, 2016 Download for free at http://cnx.org/content/col11448/1.10
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