MUTUAL RELATIONS OF ORGANISMS IN NATURE

Výukový materiál EK 01 - 21Tvůrce: Ing. Marie Jiráková

Tvůrce anglické verze: Mgr. Milan SmejkalProjekt: S anglickým jazykem do dalších

předmětůRegistrační číslo: CZ.1.07/1.1.36/03.0005

Tento projekt je spolufinancován ESF a SR ČR

RELATIONSHIPS BETWEEN ORGANISMS Relations between individuals of one

species - intraspecific Relations between individuals of

different species - interspecific

RELATIONSHIPS BETWEEN ORGANISMS Competition Basic relationship Fight for the life conditions - water, space,

light, food Between individuals of the same species

and other species Among the individuals of one species -

a fight for a territory - singers - competition for a selection of a partner - deer fights

RELATIONSHIPS BETWEEN ORGANISMS

It is often true, that the one who comes the first is the „winner“ - trees – „ Finders keepers“

Plants can compete with each other by means of the roots, they also can use secretions – wormwood, couch. This competition may lead to suppression of other species, or to establish a state of equilibration

Species can exist one next to another => coexistence

RELATIONSHIPS BETWEEN ORGANISMS Predation: Among the species One body becomes a prey to the other Predator x pray Predator – carnivore or herbivore Carnivore kills the prey, herbivore may not kill the

organism => protective measures Plants - substances that advise the predator - onion - spiny outgrowths on the leaves and stems Animals - colour, smelling feces

RELATIONSHIPS BETWEEN ORGANISMS

Parasitism: Organisms sponge on the bodies or the

metabolic products of other organisms A special type of predation Parasite x host Real parasite (holoparasite) -

heterotrophs Hemiparasite –autotrophs – only

needs minerals from the host - mistletoe

RELATIONSHIPS BETWEEN ORGANISMS Ectoparasites (external) x endoparasites (internal) They feed on the body fluids, tissues, body

parts ... Some organisms are parasites only at a certain

stage of development For example. A flea: a larva lives freely and eat

organic residues and the adults feed on blood Endoparasites – Schistosoma haematobium -

blood flukes =>cystitis Ectoparasites – fleas, lice, ticks

RELATIONSHIPS BETWEEN ORGANISMS A lot of parasites are pathogens Especially those feeding on body fluids In the Middle Ages there were fleas

that carried the plague bacteria Today, for example ticks, which can

transmit viruses that cause meningitis and bacteria that are causing Lyme disease

RELATIONSHIPS BETWEEN ORGANISMS Symbiosis: Fixed coexistence of two species Mutually beneficial co-existence -

growing, food, reproduction Lichen - sponge + green algae Legume plants + bacteria can bind

nitrogen

RELATIONSHIPS BETWEEN ORGANISMS Protocooperation : The relationship between pollinators

and plants Comparatively free link They feed on plant juices + pollinating

plants Sometimes only one species of an

insect can pollinate certain plants

RELATIONSHIPS BETWEEN ORANISMS Cooperation: Cooperation of individuals A bird honeyguide feeds on honey and

beeswax in most species and it can break even bee nests. Its screaming is heard by baboons or honey badgers and they can take honey from the nest.

Or a bird honeyguide + natives

WORKSHEET - QUESTIONS

What is a hemiparasite? Why are species in the wild competing? What is symbiosis? What are the types of parasites? What is the coexistence of a sponge

with green algae in a lichen?

SOURCES

BRANIŠ, Martin. Základy ekologie a ochrany životního prostředí: učebnice pro střední školy. 3., aktualiz. vyd. Praha: Informatorium, 2004, 203 s. ISBN 80-733-3024-5.