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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

If Jane was in room(B) while her mother Stella was in room (Y). Jane was cooking fish, her mother came to smell the good scent, By what process did her mother came to smell the scent
Neimar Reply
Is it a serious question?
Ehsan Reply
what's the question
Joseph
how many days do a bean seed take to germinate
Nando
what is DNA
Yahaya Reply
genetic information
MG
Deoxyribonucliec acid (DNA) is the cell's hereditary material that contains instructions for growth, development and reproduction.
Joseph
ok
oly
what's different between sex and gender
oly
Are there differences between sex and gender?
Theo
lol
Andrew
describe an experiment to show that plants require light for photosynthesis
Diyara Reply
uuh... putting a plant in a dark closet... and another in a light enviroment?
Anastasiya
What's an amoeba
Bigger Reply
An amoeba is a cell or an organism that has the ability to ulter it's shape.
Joseph
An amoeba has an irregular shape and it changes constantly,it's a unicellular organism belong to a group called protists it has a pseudopodia used for locomotion and ingestion...
Emmanuel
amoeba is an organism that has an inregular shape which changes constantly
Cashizz
amoeba is an unicellular organism that uses pseudopodia,it does not have a constant shape
Alohan
what is the difference between DNA and RNA
Alohan
DNA with oxygenated but RNA without oxygenated
qax
what is the mode of nutrition of fungi
Survive
asexual
qax
amoeba are protozoa with one cell and no fixed shape
James
heterotrophic and outrotrophic
qax
what is the between arteries and capillary
qax
arteries>arterioles>capillaries. decrease in size and thus pressure
Anastasiya
DNA deossoribonucleic acid. RNA ribonucleic acid. The difference between the two lies in a lack of one oxygen on the sugar in DNA. Also: in DNA the azotate bases are Guanine, Citosine, Adenine and TIMINE base, the latter is replaced by URACILE in RNA. DNA formes a double helix structure...
Anastasiya
... while RNA form is usually a single stand line, but it can form loops etc
Anastasiya
what is a zygote?
Darius Reply
zygote is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information necessary to form a new individual.
MG
A zygote is an organism formed after fertilization
Neimar
how do plants form a zygote
Paclina Reply
What is zygote
Van
what is zygote
Darius
Zygote is located inside the ovule, which is present in the ovary.
MG
zygote is a eukaryotic cell formed by a fertilization event between two gametes. The zygote's genome is a combination of the DNA in each gamete, and contains all of the genetic information necessary to form a new individual.
MG
Okay
Van
what is biology?
Aadan Reply
biology is the study of living n non living organism
Kelsia
what is procotist?
Kelsia
Biology is the branch of science that deals with the study of living and non living things
Neimar
Describe at least two major changes to the animal phylogenetic tree that have come about due to molecular or genetic findings.
Tamala Reply
what is herbarium sheet
Ramreichon Reply
Which of the following is not a characteristics of all living organisms? A. Excretion B. Photosynthesis C. Reproduction D. Respiration
Abel
B.
Anastasiya
B photosynthesis
Survive
general equation for photosynthesis
Ojasope Reply
6CO2 + 6H2O + solar energy= C6H1206+ 6O2
Anastasiya
meaning of amino Acids
AJAYI Reply
An aminoacid is a base unit molecule for proteins. It s formed by a central Carbon, to which are attached: an amminic Group, a carbossilic Group, an H hydrogen, and an R group ( which varies for each different aminoacid). Glycin is the only aminoacid to have for an R group a simple H hydrogen.
Anastasiya
H NH2-C-COOH R this is the not ionized form but usually they are ionized, with NH+ and COO-
Anastasiya
The R group, the lateral Chain, is responsible for the characteristics of the aminoacid.
Anastasiya
* NH2+
Anastasiya
J=1 jar daq
Van
a diagram of an adult mosquito
mubarak Reply
what are white blood cells
Mlungisi Reply
white blood cell is part of the immune system. that help fight the infection.
MG
what about tissue celss
Mlungisi
Cells with a similar function, form a tissue. For example the nervous tissue is composed by cells:neurons and glia cells. Muscle tissue, is composed by different cells.
Anastasiya
white blood cells are components of blood that help the body fight diseases
Neimar
I need further explanation coz celewi anything guys,,,
Calvin Reply
hey guys
Isala
on what?
Anastasiya
hie
Lish
Yes
ANDY
Please define mitosis for me
Juliet
mitosis is a process where a single cell divides into two identical daughter cells(cell division)
Sani
Kk
Juliet
yes
Sani
What about meiosis
Juliet
Meiosis is a process that produces gametes. From a single cell, 4 daughter cells (gametes) are formed.
Anastasiya
What is a tissue respiration
Juliet

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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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