INGLES

 :  TEACHER  MARGARITA 

We present united protista.

                             
Valentina Anzola Orrego

 

protist kingdom All unicellular organisms are placed under the Protist Kingdom. The term Protista was first used by Ernst Haeckel in the year 1886. This kingdom forms a link between other kingdoms of plants, animals and fungi. Protists represent an important step in early evolution. Early protists evolved probably 1.7 billion years ago. Protista members are primarily aquatic in nature. It is a very large group comprising at least 16 phyla. Many protists, such as algae are the primary producers in the aquatic ecosystem, some protists are responsible for serious human diseases such as malaria and sleeping sickness

Kingdom Protista Definition

Kingdom Protista is a diverse group of eukaryotic organisms. The protists are unicellular, some are colonial or multicellular, which have no specialized tissue organization. Simple cellular organization distinguishes protists from other eukaryotes. The cell body of the protists contains a nucleus that is well defined and organelles attached to the membrane. Some have flagella or cilia of locomotion. Reproduction in protists is both asexual and sexual.

General characteristics of the Protista Kingdom are the following:
• They are simple eukaryotic organisms.
• Most organisms are unicellular, some are colonial and some are multicellular like algae.
• Most protists live in water, some in moist soil or even the body of plants and humans.
• These organisms are eukaryotic, as they have a membrane-bound core and endomembrane systems.
• They have mitochondria for cellular respiration and some have chloroplasts for photosynthesis.
• The nuclei of protists contain multiple strands of DNA, the number of nucleotides are significantly lower than complex eukaryotes.
• The movement is often by flagella or cilia.
• Protists are multicellular organisms, not a plant, animal or fungus.
• Breathing - cellular respiration is an aerobic process mainly, but some that live in the mud under the ponds or in the digestive tract of the animals are strict facultative anaerobes.
• Nutrition - which can be both hetreotrophic or autotrophic.
• The flagellates are feeding the filter, some protists feed by the process of endocytosis (formation of food vacuole because it envelops a bacterium and extends its cell membrane).
• Reproduction, - some species have a complex life cycle that involves multiple organisms. Example: Plasmodium. Some reproduce sexually and others asexually.
• They can reproduce by mitosis and some are capable of meiosis by sexual reproduction.
• They form cysts in adverse conditions.
• Some protists are pathogens of animals and plants. Example: Plasmodium falciparum causes malaria in humans.
• Protists are the main components of plankton.
Classification Protista Unido
 of cytoplasm known as pseudopodia. The pseudopod is used for movement and feeding. During the formation of the pseudopodia the cytoplasm flows in the lobe causing the lobe to 'exude' and grow. Because of this the pedopodians have a 'blob like appearance. Example: Amoeba, foraminiferofauna benthic.


                                 

Phylum Mas tigophora (Zooflagellata) - These protozoa move with the help of the flagella. Most of them are parasites. Many flagellates are seen in the intestine of humans, in termites and other animals, some flagellates are harmful. Example: Trypanosoma gambiense causes sleeping sickness in cattle and humans.

                                                    

Phylum Ciliophora (ciliates) - The protozoa of this phylum move with hair like structures called cilia. The cilia stick out of their cells. The movement of the cilia is like rowing, it swings back and forth for the movement and rapid beat of the cilia causes the movement of the organism. Cilia is also used to sweep food particles in the body. Example: Paramecium - It is a ciliate protozoan found in freshwater and ponds. It is commonly known as the animal shoe cule.

                                   

Phylum Sporozoa - All members of this phylum have no mobility and parasitic. They form spores and hence their name sporozoa. They lack structures of locomotion and are carried in their hosts by their bodily fluids. Many sporozoans cause serious diseases in humans. Example: Plasmodium - this parasite that causes malaria in humans.

Plant-like protists - ALGAE

similar plant protists have chlorophyll like that of plants. The green substance in their cells that allows them to photosynthesis bu food. They produce and release oxygen like plants. It is believed to be the most oxygen supply on Earth is from the protists of similar plants. Protists similar to plants are the main source of food and primary producers for aquatic organisms.


Phylum Chlorophyta (green algae) - Green algae include unicellular and multicellular algae. They are mostly fresh water. The body is similar to a talus blade. They have cellulose and pectin cell walls. The food is reserve starch that is stored in pyrenoids. Example: Spirogyra - is a unicellular green alga,

                                                      

                 Mariana Herrera Osorio

 HABITAD: 

None of its representatives is fully adapted to exist in the air, so those that are not directly aquatic, are developed in humid terrestrial environments or the internal environmet of other organisms. Cellular organization: Eukaryotes (cells with nucleus), unicellular or multicellular. Larger, brown algae of the genus laminaria, can measure tens of meters, but microscopic forms predominate

MANUELA MORALES VARGAS

.THE PROTIST KINGDOM HAS PLAYED A CENTRAL ROLE IN THE ORIGIN AND EVOLUTION OF THE EUKARYOTIC.  SEVERAL GROUPS OF EUKARYOTES INDEPENDENTLY DEVELOPED  MULTICELLULARITY HAVING AS ORIGIN A PROTIST: ANIMALS, FUNGI, PLANTS, RED ALGAE AND BROWN ALGAE

DESPITE THIS DEFINITION PROVIDED BY THE DICTIONARY OF THE ROYAL SPANISH ACADEMY (RAE), THERE ARE EXPERTS WHO ALSO INCLUDE MULTICELLULAR ORGANISMS IN THE PROTIST KINGDOM

 IN THIS SENSE, ALL THE ORGANISMS OF EUKARYOTIC TYPE THAT, BY THEIR CHARACTERISTICS, DO NOT FORM PART OF THE KINGDOMS OF THE FUNGI, THE PLANTS AND THE ANIMALS, WOULD COMPOSE THE PROTISTA KINGDOM. THESE DIFFERENCES OF CRITERIA MEAN THAT THERE IS NO SINGLE DEFINITION OF THE PROTIST REALM. BIOLOGISTS DO NOT END UP AGREEING ON WHICH ORGANISMS ARE PROTISTS AND WHICH ORGANISMS SHOULD NOT BE INCLUDED IN THIS CLASSIFICATION

LIVING ORGANISMS THAT HAVE A SINGLE EUKARYOTIC CELL ARE QUALIFIED AS PROTISTS. THE PROTIST KINGDOM, THEREFORE, IS THAT FORMED BY THIS CLASS OF LIVING BEINGS.   PROTIST KINGDOM DESPITE THIS DEFINITION PROVIDED BY THE DICTIONARY OF THE ROYAL SPANISH ACADEMY (RAE), THERE ARE EXPERTS WHO ALSO INCLUDE MULTICELLULAR ORGANISMS IN THE PROTIST REALM. IN THIS SENSE, ALL THE ORGANISMS OF EUKARYOTIC TYPE THAT, BY THEIR CHARACTERISTICS, DO NOT FORM PART OF THE KINGDOMS OF THE FUNGI, THE PLANTS AND THE ANIMALS, WOULD COMPOSE THE PROTISTA KINGDOM. THESE DIFFERENCES OF CRITERIA MEAN THAT THERE IS NO SINGLE DEFINITION OF THE PROTIST REALM. BIOLOGISTS DO NOT END UP AGREEING ON WHICH ORGANISMS ARE PROTISTS AND WHICH ORGANISMS SHOULD NOT BE INCLUDED IN THIS CLASSIFICATION

THERE ARE THOSE WHO DIVIDE THE PROTIST KINGDOM INTO THREE SUBREGIONS: ARCHAEZOA, EUGLENOZOA AND PROTOZOA. IN THE SUBREINO

MARIA PAZ ACOSTA HIDALGO

Asexual Reproduction

Cellular division: It is the reproduction applied by amoebas and other simple organisms, they produce offspring asexual reproduction method is by spores, it is common in protists similar to fungi, in this case there is a multiple division that gives rise to even a hundred cells with the ability to develop as new protists.

Gemmation: In this case the son nucleus adheres to the cytoplasm of its mother cell (the edge of the cell), at the moment of separation, it will start with a part of the cytoplasm. It is common in ciliates and in Tritrichomonas.

Sexual reproduction: When there is environmental stress, that is, circumstances that require ability to adapt to the environment (impossible through asexual reproduction) protists are forced to exchange genetic material.

In this case two stem cells are required for a meiosis process where each will form half of the genetic material of the daughter cell (haploid gametes), then join them forming a zygote. without the need for genetic material contributed by another individual.

The protist kingdom comprises a huge variety of eukaryotic organisms, mainly unicellular and some simple multicellular forms. Photosynthetic protists are classified into six groups according to their pigmentation.

Diatoms and brown-gold algae are unicellular organisms and usually reproduce asexually, but in some cases they also do so by syngamy (the union of gametes in fertilization).

Green algae have often complex reproductive cycles. In species with sexual cycles, gametes of opposite mating types may be similar in size and structure (isogamy), different in size but both mobile (anisogamy) or different in size and one of them usually the largest, not mobile (oogamy ).

Some green algae have alteration of generations, in which a haploid phase alternates with a diploid. The first produces haploid gametes that fuse to form the zygote. The zygote produces spores (a single cell that, unlike a gameta, can produce an adult organism without being combined with another cell) by meiotic division. In organisms with alteration of generations, the haploid spore germinates.

Mucilaginous molds also reproduce by the formation of spores. Water molds do it both sexually and asexually.

The other two groups of photosynthetic protists are brown and red algae, and dinoflagellata.