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Watch this video to see how plants respond to a stimulus—from opening to light, to wrapping a tendril around a branch, to capturing prey.

Reproduction

Single-celled organisms reproduce by first duplicating their DNA, and then dividing it equally as the cell prepares to divide to form two new cells. Multicellular organisms often produce specialized reproductive germline cells that will form new individuals. When reproduction occurs, genes containing DNA are passed along to an organism’s offspring. These genes ensure that the offspring will belong to the same species and will have similar characteristics, such as size and shape.

Growth and development

Organisms grow and develop following specific instructions coded for by their genes. These genes provide instructions that will direct cellular growth and development, ensuring that a species’ young ( [link] ) will grow up to exhibit many of the same characteristics as its parents.

A photograph depicts a mother cat nursing three kittens: one has an orange and white tabby coat, another is black with a white foot, while the third has a black and white tabby coat.
Although no two look alike, these kittens have inherited genes from both parents and share many of the same characteristics. (credit: Rocky Mountain Feline Rescue)

Regulation

Even the smallest organisms are complex and require multiple regulatory mechanisms to coordinate internal functions, respond to stimuli, and cope with environmental stresses. Two examples of internal functions regulated in an organism are nutrient transport and blood flow. Organs (groups of tissues working together) perform specific functions, such as carrying oxygen throughout the body, removing wastes, delivering nutrients to every cell, and cooling the body.

Homeostasis

A photos shows a white, furry polar bear.
Polar bears ( Ursus maritimus ) and other mammals living in ice-covered regions maintain their body temperature by generating heat and reducing heat loss through thick fur and a dense layer of fat under their skin. (credit: “longhorndave”/Flickr)

In order to function properly, cells need to have appropriate conditions such as proper temperature, pH, and appropriate concentration of diverse chemicals. These conditions may, however, change from one moment to the next. Organisms are able to maintain internal conditions within a narrow range almost constantly, despite environmental changes, through homeostasis    (literally, “steady state”)—the ability of an organism to maintain constant internal conditions. For example, an organism needs to regulate body temperature through a process known as thermoregulation. Organisms that live in cold climates, such as the polar bear ( [link] ), have body structures that help them withstand low temperatures and conserve body heat. Structures that aid in this type of insulation include fur, feathers, blubber, and fat. In hot climates, organisms have methods (such as perspiration in humans or panting in dogs) that help them to shed excess body heat.

Energy processing

Photo shows a California condor in flight with a tag on its wing.
The California condor ( Gymnogyps californianus ) uses chemical energy derived from food to power flight. California condors are an endangered species; this bird has a wing tag that helps biologists identify the individual. (credit: Pacific Southwest Region U.S. Fish and Wildlife Service)

Questions & Answers

I want more mcqs please
Uday Reply
more what?
Everine
what is meant by the term decarboxylation
Lolem
explain the role natural selection in the evolution of organisms
Lolem
the population produces more than What the environment can support. some organisms adapt well to the environment than others. the less adapted ones disappear leaving the more adapted in the environment.
ATIKPO
What are the Advantage of electron microscope over light microscope?
Liticia Reply
an electronic microscope uses electronic so it's more efficient
Cosmas
It helps to view specimen accurately
ATIKPO
what are nymph nodes?
Lydia Reply
what imeosis
Martin
because the surface tension is tight like a skin
david Reply
k
Lydia
what is genetic
Nad Reply
what is écosystème
Nad
what is écosystème
Nad
what is écosystème
Nad
what is écosystème
Nad
discuss adaptations of flight in birds
Cassim Reply
what is an enzymes
Joseph Reply
mention two types of metabolic
Joseph
what is a cell?
Joseph
is the biological catalyst that speed up chemical reaction in the living thing
Cassim
an enzymes is a biological catalyst that speed up a chemical reaction in living organisms and it is protein in nature
Idah
enzymes are protein that act as biological catalysts
Maria
what agglutriation
Idah
enzymes are biological catalysts that speed up the chemical reactions in a living organism
Ainamani
what is antecology
Isaac
agglutination is the process by which rhesus factor of blood react during blood transfusion
Paul
Enzymes are biological catalysts, proteins in nature, functioning to increase the rate of chemical reactions and remain unchanged at the end of the reaction.
Everine
Be4 transfusions are performed, a major cross-match made by mixing serum frm the recipient wizblood cells frm the donor.If the types don't match eg if the donor z type A,and recipient z type B,the recipient's antibodies attach 2 the donor's red blood cells and form bridges thatcoz the cells2clump.
Everine
Enzymes are organic catalyst that speeds up the rate or chemical rxn without, being alterect in the process
Henry
an enzyme is a biological catalyst that speed up chemical reactions.
ATIKPO
1.anabolism 2.catabolism
ATIKPO
a cell is the basic functional and structural unit of a living organism.
ATIKPO
what are the two types of sugar contents in carbohydrate?
Jimmy
what is photosynthesis
Conast Reply
photosynthesis is the process by which green plants manufacture their own food from water and carbon dioxide using sunlight as a source of their energy releasing oxygen as a by-product.
Everine
what is the function of thé utérus
Nad
what are runners
Godfrey Reply
what is an environment
Bwambale Reply
diagrams are not indicated, why?
Simon Reply
diagrams for what?
Everine
A vaccination is a treatment which makes the body stronger against an infection. The body fights infections using the immune system, which is made up of millions upon millions of cells including T cells and B cells.
Nworie
define the term immunity
Everine
can simply defined as an exemption from an attack
Nworie
is the ability of an organism to resist a particular infection or toxin by a specific antibodies or sensitized white blood cells
Adeb
what is a blood group?
Lydia
A blood group is any different type that human blood can be separated into for medical purposes.
Everine
It is the body ability to resist infection .
ATIKPO
difference between cell and cell membrane
Sunday Reply
cell is a basic unit of living body however cell membrane is a protective layer of cell.
Suhail
very good
Everine
which topic would you like to discuss today?
Everine
vaccine
Nworie
what do you understand by the term vaccine?
Everine
guy I need the answer of this question what occurs during photosynthesis
REAL Reply
Photosynthesis is the process that plants use to convert light into food. During this process, plants create carbohydrates starting with only carbon dioxide and water. Sunlight provides the energy that makes photosynthesis possible.
Stanley
@Stanley,that's how I could as well put it
Evans
what are different between genotype and phenotype
Martha Reply
what is light microscope and electronic microscope
Martha
what occurs during photosynthesis
Martha
what are importance of biology
Martha
what is the meaning of computer science
Martha
genotype is the genetical constitution of the gene
Ainamani
what is ecology
Adeyemo Reply
what is zoology
Adeyemo
zoology branch of biology that study animals
Moses
a branch of biology which deals with the study of animals
Anita

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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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