What is biology ?
simple meaning of biology is study of life (living things )
biology is the greek language word not english
biology = bio +logy
bio = living things or life
logy = study
biology = study of living things
History of biology
Aristotle starts the classification of living organisms into two types
1. plants
2. animals
primitive biology scientists are galen and aristotle.
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we got primitive descriptive records regarding biology from aristotle and galen
before Aristotle we don't have any imformation in the form of description.
aristotle is consider to be as father of biology
aristotle is the only responsible person who start the living organisms classification
according to aristotle living things are two types based on their habitate 1. plant 2. animal
but however after wards we invented so many species which show both plant and animal characters.
now the question is " in which category we have to include these newly invented species "
after wards there are so many classifications are announced among them whittaker five kingdom classification is populared.
whittaker five kingdom classification
Plantae :Plants, also called green plants (Viridiplantae in Latin), are living organisms of the kingdom Plantae including such multicellular groups as flowering plants, conifers, ferns and mosses, as well as, depending on definition, the green algae, but not red or brown seaweeds like kelp, nor fungi or bacteria.
PARTS OF LEAVE :
TYPES OF LEAVES :
Venation: the vascular tissues in leaves forms a system of veins. In dicots the veins form a closed network called netted or reticulate venation. In monocots the larger veins are parallel to each other called parallel venation.
PARTS OF FLOWER :
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TYPE OF FLOWERS :
Below, we have listed 39 different types of flowers which florists often use to help you understand the common types of flowers which are sent when you buy flowers.
TYPES OF OVARIES :
'
The terminology of the positions of ovaries is determined by the insertion point, where the other floral parts (perianth and androecium) come together and attach to the surface of the ovary. [1] If the ovary is situated above the insertion point, it is superior; if below, inferior.
An ovary becomes superior during anthesis (flower formation) when the upper portion of the ovary grows more than the lower part[citation needed].
More specifically, a half-inferior ovary has nearly equal portions of ovary above and below the insertion point. Other varying degrees of inferiority can be described by other fractions. For instance, a "one-fifth inferior ovary" has approximately one fifth of its length under the insertion point. Likewise, only one quarter portion of a "three-quarters inferior ovary" is above the insertion.
TYPE OF FLOWERS :
Types of Flowers
Florists often use a wide variety of flowers when creating an arrangement. Normally, a bouquet will consist of the featured or main blooms and an assortment of filler flowers to accent the main blooms. Florists often try to explain what certain flowers look like to their customers over the phone, but this can be a difficult process.Below, we have listed 39 different types of flowers which florists often use to help you understand the common types of flowers which are sent when you buy flowers.
Alstroemeria Friendship |
Amaryllis Splendid beauty |
Anemone Anticipation |
Anthurium Hospitality |
Aster Patience |
Birds of Paradise Joyfulness |
Bouvardia Enthusiasm |
Carnations Pride and beauty |
Cushion Chrysanthemum Fidelity |
Daisy Fidelity |
Standard Chrysanthemum Fidelity |
Daffodil Chivalry |
Delphinium Heavenly |
Freesia Innocence |
Gladiolus Strength of character |
Heather Admiration |
Hyacinth Constancy |
Hydrangea Heartfelt |
Iris My compliments |
Larkspur Levity |
Lilac Youthful innocence |
Asiatic Lily Majesty |
Oriental Lily Majesty |
Lisianthus Outgoing |
Cymbidium Orchid A belle |
Dendrobium Orchid A belle |
Oncidium Orchid A belle |
Phalaenopsis Orchid A belle |
Peony Bashful |
King Protea Daring |
Queen Annes Lace Sanctuary |
Ranunculus Radiant |
Roses Love |
Snapdragon Desire |
Statice Remembrance |
Stock Lasting beauty |
Sunflower Pure thoughts |
Sweet Pea Delicate pleasure |
Tulips Declaration of love |
TYPES OF OVARIES :
'
Classification based on position
Superior ovary
A superior ovary is an ovary attached to the receptacle above the attachment of other floral parts. A superior ovary is found in types of fleshy fruits such as true berries, drupes, etc. A flower with this arrangement is described as hypogynous. An example is Hypericum calycinum.An ovary becomes superior during anthesis (flower formation) when the upper portion of the ovary grows more than the lower part[citation needed].
Inferior ovary
An inferior ovary lies below the attachment of other floral parts. A pome is a type of fleshy fruit that is often cited as an example, but close inspection of some pomes (such as Pyracantha) will show that it is really a half-inferior ovary. Flowers with inferior ovaries are termed epigynous. Some examples of flowers with an inferior ovary are orchids (inferior capsule), Fuchsia (inferior berry), Asteraceae (inferior achene-like fruit, called a cypsela).Half-inferior ovary
A half-inferior ovary (also known as “half-superior”, “subinferior,” or “partially inferior,”) is embedded or surrounded by the receptacle.[2] This occurs in flowers of the Lythraceae family, which includes the Crape Myrtles. Such flowers are termed perigynous or half-epigynous. In some classifications, half-inferior ovaries are not recognized and are instead grouped with either the superior or inferior ovaries.More specifically, a half-inferior ovary has nearly equal portions of ovary above and below the insertion point. Other varying degrees of inferiority can be described by other fractions. For instance, a "one-fifth inferior ovary" has approximately one fifth of its length under the insertion point. Likewise, only one quarter portion of a "three-quarters inferior ovary" is above the insertion.
plants are divided into two categories
1. flowering plants called phanerogams
2. Non-flowering plants called cryptogams
flowering plants (phanerogams ) : a) angiosperms
b) gymnosperms
a) angiosperms : the seeds are enclosed in the fruits.
example : mango, papaya etc.
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B) gymnosperms : seeds are not enclosed in the fruits . the seeds are exposed as cones etc.
ex : cycas, pinus
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NON-FLOWERING PLANTS( CRYPTOGAMS ) : A) THALLOPHYTES
B) BRYOPHYTA
C) PTERIDOPHYTA
A) THALLO PHYTES : The thallophytes are a polyphyletic group of non-mobile organisms traditionally described as "relatively simple plants" or "lower plants" with undifferentiated bodies (thalli). They were a defunct division of Kingdom Plantae, the Thallophyta (or Thallobionta) that included fungus and algae, and lichens occasionally bacteria and the Myxomycota.They have a hidden reproductive system and hence they are also called cryptogamae.
NORMAL THALLOPHYTES WHICH WE COMMONLY SEE IS
1. POND WATER
2. CHLAMYDOMONAS
3. SPYROGYRA
B) BRYOPHYTES : Bryophyte is a traditional name used to refer to all embryophytes (land plants) that do not have true vascular tissue and are therefore called 'non-vascular plants'.[1] Some bryophytes do have specialized tissues for the transport of water; however since these do not contain lignin, they are not considered to be true vascular tissue.[2] Currently bryophytes are thought not to be a natural or monophyletic group; however the name is convenient and remains in use as a collective term for mosses, hornworts, and liverworts. Bryophytes produce enclosed reproductive structures (gametangia and sporangia), but they produce neither flowers nor seeds, reproducing via spores. The term bryophyte comes from Greek βρύον, bryon, "tree-moss, oyster-green" + φυτόν - phyton "plant".
NORMAL BRYOPHYTES WHICH WE CAN SEE IS 1. WET WALL
2. MOIST SOIL
3. MOSS PLANT
PTERIDO PHYTA :
3. MOSS PLANT
PTERIDO PHYTA :
a division of flowerless green plants that comprises the ferns and their relatives.
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MOST COMMON PTERIDOPHYTA IS FERNS
FUNGI :
The Kingdom Fungi includes some of the most important organisms, both in terms of their ecological and economic roles. By breaking down dead organic material, they continue the cycle of nutrients through ecosystems. In addition, most vascular plants could not grow without the symbiotic fungi, or mycorrhizae, that inhabit their roots and supply essential nutrients. Other fungi provide numerous drugs (such as penicillin and other antibiotics), foods like mushrooms, truffles and morels, and the bubbles in bread, champagne, and beer.
Fungi also cause a number of plant and animal diseases: in humans, ringworm, athlete's foot, and several more serious diseases are caused by fungi. Because fungi are more chemically and genetically similar to animals than other organisms, this makes fungal diseases very difficult to treat. Plant diseases caused by fungi include rusts, smuts, and leaf, root, and stem rots, and may cause severe damage to crops. However, a number of fungi, in particular the yeasts, are important "model organisms" for studying problems in genetics and molecular biology.
- Division Pteridophyta: classes Filicopsida (ferns), Sphenopsida (horsetails), and Lycopsida (clubmosses)
MOST COMMON PTERIDOPHYTA IS FERNS
FUNGI :
The Kingdom Fungi includes some of the most important organisms, both in terms of their ecological and economic roles. By breaking down dead organic material, they continue the cycle of nutrients through ecosystems. In addition, most vascular plants could not grow without the symbiotic fungi, or mycorrhizae, that inhabit their roots and supply essential nutrients. Other fungi provide numerous drugs (such as penicillin and other antibiotics), foods like mushrooms, truffles and morels, and the bubbles in bread, champagne, and beer.
Fungi also cause a number of plant and animal diseases: in humans, ringworm, athlete's foot, and several more serious diseases are caused by fungi. Because fungi are more chemically and genetically similar to animals than other organisms, this makes fungal diseases very difficult to treat. Plant diseases caused by fungi include rusts, smuts, and leaf, root, and stem rots, and may cause severe damage to crops. However, a number of fungi, in particular the yeasts, are important "model organisms" for studying problems in genetics and molecular biology.
A group of fungi called dermatophytes degrade keratin. They exist on the dead skin of humans provided other environmental conditions are met. They become a problem for the host when the skin remains moist and warm for long periods. Each fungus appears to have specific hosts and is found in specific locations in most cases. However, given sufficient inoculum and appropriate conditions, many dermatophytes can swap hosts and locations.
Many of you will be infected by one of these fungi at some time during your life. Tinea and ringworm are the common names given to the disease caused by dermatophytes. The names are usually associated with the place or shape of the infection reaction. The fungus causes distress because the metabolites it releases cause an allergic or immunological reaction. Removal of the infection removes the response.
The fungi are found in three anamorphic genera of Ascomycota; Trichophyton, Epidermophyton and Microsporum. They transfer from host to host usually as infected skin cells. Thus treatment of the condition and removal of the inoculum are necessary for control of epidemics. For instance, flakes of skin may lodge in carpet of bedrooms or on wet floors of change rooms. The fungi rarely cause significant problems.
Candida may also cause surface infection, but is dealt with below where its properties will be discussed.
Protista:
Some members of Kingdom Protista are unicellular, others are colonial, and yet others are multicellular. Note that in the colonial forms, all the cells are similar with similar, generalized functions, whereas in the truly multicellular species, the “body” of the organism consists of a variety of types of cells, each type with its own specialized function. These organisms are all eukaryotes (they have a true nucleus). They all need some kind of a water-based environment--which can be fresh or marine water, snow, damp soil, polar bear hairs--in which to live. All are aerobic and have mitochondria to do cellular respiration, and some have chloroplasts and can do photosynthesis. Most of them reproduce or grow by mitosis, and some reproduce by meiosis and fertilization. Many can form cysts in adverse conditions. Protists are a major component of plankton.
Protists are grouped into three major, unofficial categories based on means by which they obtain nutrition. These are the Protozoa, the Algae, and the Fungus-like Protists. For some reason, botanists use the word “Division” to mean the same taxonomic level as “Phylum”, and since, way back everything was lumped in as either a plant or an animal, taxonomists who study Kingdom Protista (and those who study Kingdom Fungi) also still use the word “Division” to mean “Phylum”, so for example, when “Division Rhizopoda” is listed below, that means the same thing as saying “Phylum Rhizopoda”.
Protozoa:
These protists are animal-like, especially in their nutrition. They ingest their food by phagocytosis. Some have mouth-like structures into which the prey is put while others use pseudopodia to move and to engulf prey. Typical prey include bacteria and other smaller one-celled organisms.- Division Rhizopoda:
An example of a member of this Division is genus Amoeba, a fresh-water dweller. Protists in this group are unicellular and have pseudopodia. Some secrete shells around themselves, while others do not. None of them have flagella, cilia, or meiosis. Entamoeba histolytica is a parasitic form that causes amoebic dysentery. These colonize the colon and feed on bacteria, causing symptoms that range from mild diarrhea to dysentery. Typically periods of watery diarrhea, often containing blood, may alternate with constipation, and often there is flatulence and abdominal cramping. Entamoeba can be directly spread (anal sex), or indirectly spread (by drinking contaminated water). Fresh fruits and vegetables may be unsafe if fertilized with human feces, watered with contaminated water, or prepared by a person with it on his/her hands.
- Division Apicomplexa:
- These are all parasites and form tiny, infectious spores. All have complex life cycles. An example is Plasmodium vivax, which causes malaria, for which certain species of mosquitoes are the secondary host. It is also possible to become infected with Plasmodium parasites from a transfusion from an infected person or if a drug addict shares a syringe with an infected person. One stage in this complicated life cycle grows in the mosquito, the next stage in the newly-infected person’s liver, and the next stage invades the person’s red blood cells, rupturing the RBCs as the parasites leave to invade other cells. Symptoms include cyclical alternating chills, fever, and sweating which at first, can be mistaken for flu. While usually less than 1% of the RBCs are infected, often malaria causes anemia due to the smaller number of RBCs. Often the spleen and liver become enlarged as they try to deal with the dying RBCs. Malaria is treated with extract from the quinine tree. Remember that people with sickle-cell are more resistant because when a malaria parasite enters a RBC, the RBC sickles, killing the parasite, thereby preventing it from multiplying and spreading.
- Division Zoomastigophora:
This Division contains some organisms which are free-living, others which are symbionts, and yet others which are parasites. An example of a symbiotic member of this Division is the protozoans which live in the gut of termites and digest cellulose in the wood the termites eat. An example of a parasitic form would be Trypanosoma gambiense, which causes African sleeping sickness and is spread by the bite of the tsetse fly. Symptoms include irregular fever, general swelling of the lymph nodes, skin eruptions, and areas of painful local swelling. Eventually CNS symptoms like tremors, headache, apathy, and convulsions appear and become worse, leading to eventual coma and death. Early on, the parasites are found in blood and lymph, but later only in the person’s cerebrospinal fluid.
- Division Ciliophora:
An example of an organism in this Division is Paramecium. These protozoans are solitary, fresh water organisms and use cilia to move. They have probably the most complex structure and organization of all cells. Rather than one nucleus, they have a larger macronucleus and several smaller micronuclei. They use a form of sexual reproduction called conjugation in which some of the micronuclei are exchanged between the two individuals involved.
Algal Protists
These protists are photosynthetic; their nutrition is plant-like. Almost all of them have chlorophyll A, most have chlorophyll C, but only a few have chlorophyll B. They also have a variety of carotenoids and other pigments, and frequently they are grouped into Divisions based on similarities in pigments.- Division Dinoflagellata:
- These are abundant in plankton, occasionally occurring in large numbers. They can occasionally become so numerous that the water looks red, thus this algal bloom (meaning there are large numbers of them, having nothing to do with flowers, which they do not have) is called Red Tide. Because Dinoflagellates are toxic to humans, it is not safe to eat “shellfish” (clams, etc.) collected where Red Tide is occurring (the Protists get inside the clam shell and cannot be easily removed). Dinoflagellates are bioluminescent, that is, they are able to produce light like lightening bugs, and at night during Red Tide, the crests of the ocean waves appear to glow in the dark.
- Division Euglenophyta:
Probably the best-known example of this Division is genus Euglena. Each of these organisms has a flagellum on its anterior end, and this is used to propel the organism. They have chloroplast and, when in the light, do photosynthesis. If they are not in the light, they can also obtain nutrition by phagocytosis. To help them sense light (which they then move toward), Euglena have a light-sensitive “eyespot” or stigma near their anterior ends. This is not a true eye, in that it cannot do any image formation, but rather it is a photoreceptor which senses the light level in the organism’s environment.
- Division Chlorophyta:
- These protists are also known as the “green algae.” Their
chloroplasts and the pigments therein are similar to plants (this is
about the only group of algae with chlorophyll
B), thus it is thought that the green algae may be the evolutionary
ancestors of plants. Various species of green algae may be found in a
variety of environments including both fresh and salt water, damp soil,
the surface of snow, and within other
organisms (lichens, hydra, polar bear hair).
Chlamydomonas are unicellular and contain an eyespot (stigma), a chloroplast, two flagella, and a nucleus. Volvox are colonial and often contain darker green daughter colonies inside. Each cell posesses two flagella, enabling the colony to be mobile. There is an intercellular matrix holding the colony of cells together. Ulva is called Sea Lettuce. This is truely multicellular, with a division of labor among the various cells, and is macroscopic. The “body” is two cells thick, and there is a specially-modified “holdfast” to anchor the organism to the ocean floor. Its life cycle includes both 1n and 2n stages (see below). Closterium is a member of the sub-group called the Desmids. Some desmids form colonies, but Closterium is solitary. Its nucleus is in the center with a cone-shaped chloroplast on each side. Each chloroplast contains a series of starch-storage organelles called pyrenoids In living Closterium, each end of the cell bears a small vacuole containing several gypsum grains which “dance” by Brownian motion. Spirogyra are colonial, being organized into long filaments. Each cell contains a spiral chloroplast with pyrenoids (used to store starch) and a nucleus. They have conjugation--a type of sexual reproduction in which the contents of the male gamete cell go over into the female cell.
Many green algae, especially the multicellular ones, have both sexual and asexual stages in their life cycles, thus we must re-introduce the idea of Alternation of Generations we discussed along with meiosis. When we first discussed Alternation of Generations, we looked at a very simple diagram in which adults produced 1n gametes by meiosis, and those gametes joined by syngamy to form a new 2n generation. In reality in algae and plants, there are a few more stages in the process, thus we now need to re-visit this cycle. The 2n generation, which in humans is called an “adult,” in algae and plants is called a sporophyte because it produces spores. Within specialized reproductive structures in/on the bodies of the sporophyte, meiosis occurs to reduce the chromosome number from 2n to 1n, thus the spores which are produced are 1n. Each spore germinates and grows into a new, independent, 1n organism (which often looks totally different than the 2n generation). These 1n organisms are called gametophytes because they produce the gametes (eggs and sperm), which are still 1n. An egg and sperm unite by syngamy increasing the chromosome number from 1n to 2n, and forming a zygote which is 2n. The zygote grows into the sporophyte, and the cycle starts over. Various of the green algae go through this cycle as do members of the next two groups, the brown and red algae. Plants also go through this same cycle with some interesting modifications we will discuss later.
- Division Phaeophyta:
- These organisms are commonly known as the “brown algae.” They are multicellular and live in marine, temperate zone, costal areas. They all have a form of sexual reproduction with alternation of generations. One member of this Division with which you may be familiar is Kelp, which actually can be any of several species of seaweed in the genera Fucus and/or Laminaria. Brown algae are used in many cultures as human food, and are good sources of iodine. We need iodine for our thyroid glands, and if a person doesn’t enough iodine in his/her diet (most commonly in inland areas where iodine is not added to salt), the thyroid gland enlarges in an attempt to keep making enough thyroid hormone (which doesn’t do any good because what it’s lacking is the iodine needed to make the hormone). This enlarged thyroid is called a goiter. Laminaria also has an interesting gynecological use. If a woman is scheduled for some medical procedure for which the doctor needs access to the inside of her uterus, often a day or so beforehand, rolled-up, dried pieces of Laminaria are inserted into the opening of the woman’s cervix. As the seaweed absorbs water from her body fluids, it gently and slowly expands, gradually stretching the cervix. Thus, by the time her surgery is scheduled, her cervix has been dilated slowly and gently rather than the doctor having to forcibly and quickly (thus painfully) stretch the cervix open minutes beforehand.
- Division Rhodophyta:
- These are called the “red algae.” They also are multicellular and marine-dwelling, but are more typically found in tropical zones and deeper in the ocean. They also go through alternation of generations, Many of these (such as the Nori used in sushi) are used by humans as food, and are also good sources of iodine.
Fungus-like Protists
- Division Myxomycota:
- These organisms are called “slime molds.” They are fungus-like in their nutrition in that they absorb nutrients from their environment. Their “body” structure is unusual in that the nuclei undergo mitosis, but there is no cytokinesis--there are no individual cells with one nucleus each. Rather, the “body” is a giant, multinucleate mass of cytoplasm. Slime molds are mobile: they move by amoeboid movement, in other words, like a giant Amoeba with giant pseudopodia. They live in decayed wood and move around in between the fibers, ingesting bacteria, etc. by phagocytosis.
- Classification of protista :
- normally protista are divided into three group based on the locomotion
- Nutrition in some different types of protists is variable. In flagellates, for example, filter feeding
may sometimes occur where the flagella find the prey. Other protists
can engulf bacteria and digest them internally, by extending their cell membrane around the food material to form a food vacuole. This is then taken into the cell via endocytosis (usually phagocytosis; sometimes pinocytosis).
Nutritional types in protist metabolism Nutritional type Source of energy Source of carbon Examples Phototrophs Sunlight Organic compounds or carbon fixation Algae, Dinoflagellates or Euglena Organotrophs Organic compounds Organic compounds Apicomplexa, Trypanosomes or Amoebae Reproduction
Some protists reproduce sexually (gametes), while others reproduce asexually (binary fission).
Some species, for example Plasmodium falciparum, have extremely complex life cycles that involve multiple forms of the organism, some of which reproduce sexually and others asexually.[13] However, it is unclear how frequently sexual reproduction causes genetic exchange between different strains of Plasmodium in nature and most populations of parasitic protists may be clonal lines that rarely exchange genes with other members of their species.[14] -
flagella group
- Monera :
- Monera is the primitive unicellular micro organism. it can survive extreme hot as well as cold conditions.
- Monera (/məˈnɪərə/ mə-NEER-ə) is a kingdom that contains unicellular organisms without a nucleus (i.e., a prokaryotic cell organization), such as bacteria. The kingdom is considered superseded.[1]
The taxon Monera was first proposed as a phylum by Ernst Haeckel in 1866. Subsequently, the taxon was elevated to the rank of kingdom in 1925 by Édouard Chatton. The last commonly accepted mega-classification with the taxon Monera was the five-kingdom classification system established by Robert Whittaker in 1969.
Under the three-domain system of taxonomy, which was established in 1990 and reflects the evolutionary history of life as currently understood, the organisms found in kingdom Monera have been divided into two domains, Archaea and Bacteria (with Eukarya as the third domain). Furthermore the taxon Monera is paraphyletic. The term "moneran" is the informal name of members of this group and is still sometimes used (as is the term "prokaryote") to denote a member of either domain.[2]
Despite the fact that most bacteria were classified under Monera, the bacterial phylum Cyanobacteria (the blue-green algae) was not initially classified under Monera, but under Plantae because of the ability of its members to photosynthesise.
Blue-green algae
Main article: cyanobacteriaAlthough it was generally accepted that one could distinguish prokaryotes from eukaryotes on the basis of the presence of a nucleus, mitosis versus binary fission as a way of reproducing, size, and other traits, the monophyly of the kingdom Monera (or for that matter, whether classification should be according to phylogeny) was controversial for many decades. Although distinguishing between prokaryotes from eukaryotes as a fundamental distinction is often credited to a 1937 paper by Édouard Chatton (little noted until 1962), he did not emphasize this distinction more than other biologists of his era.[25] Roger Stanier and C. B. van Niel believed that the bacteria (a term which at the time did not include blue-green algae) and the blue-green algae had a single origin, a conviction which culminated in Stanier writing in a letter in 1970, "I think it is now quite evident that the blue-green algae are not distinguishable from bacteria by any fundamental feature of their cellular organization".[31] Other researchers, such as E. G. Pringsheim writing in 1949, suspected separate origins for bacteria and blue-green algae. In 1974, the influential Bergey's Manual published a new edition coining the term cyanobacteria to refer to what had been called blue-green algae, marking the acceptance of this group within the Monera.[25]
Characteristics of Monera
The following points related to Monera characteristics will help you understand the kingdom of classification better.
Monera are about 1 micrometer in size and complex as living molecules.
The Monera cell structure is mostly unicellular and some organisms that form groups or filaments.
These organisms are the simplest prokaryotic cell structures.
The Monera cell structure lacks nuclei and many other cell organelles.
They have a cell wall made of polysaccharides with polypeptide cross links with a chemical called peptidoglycan.
They lack enclosed sub-cellular organelles like mitochondria and only have ribosomes.
The genetic material DNA is contained in the cytoplasm called nucleoid.
Many bacterial species contain rings of DNA called plasmids.
The cytoplasm is enclosed by plasma membrane that lies beneath the cell wall.
The plasma membrane is made up of lipids and proteins.
Some Monera have hair like pilli for adhesion or tail-like flagella for locomotion.
The source of nutrition for these organisms is usually photosynthesis or chemosynthesis.
The characteristics also include the shape of the cell that includes round (cocci), rod-like (bacilli) or spiral (spirochetes or spirilla).
Reproduction is asexually through binary fission or sexually by conjugation. The process of circulation and digestion is carried out through diffusion.
The Monera kingdom includes all bacteria that may infect animals, humans and plants. But most of the members are termed as beneficial bacteria, rather than pathogenic bacteria.
The Monerans kill organisms causing pathogenic diseases, breaks down algae and can even recycle chemical pollutants like hydrogen sulfide and ammonia.
Bacteria that grow in the root nodules help break down atmospheric nitrogen into fixed nitrogen,
The bacteria that forms the natural flora of the intestines are very important for proper digestion.
One of their many characteristics also includes production of antibiotics likes streptomycin that is useful for treatment of infections
Monorans can be identified by their characteristic of cell wall that can be or not stained by Gram staining.
Most of the Monorans can survive harsh environment by producing spore coat.
Kingdom Monera Division
The kingdom Monera is divided into many sub kingdoms as well as phyla. These sub kingdoms and phyla include:
Sub-kingdom Archaebacteria: Their characteristics includes survival in harsh conditions intolerable to other organisms.
Sub-Kingdom Eubacteria: This kingdom includes all bacteria known as 'true bacteria' except archaebacteria.
Phylum Anaerobic Phototrophic Bacteria: Their characteristics includes photosynthesis that does not use water as the initial substrate and does not produce oxygen as end product.
Phylum Cyanobacteria: These monerans are blue-green bacteria that carry out photosynthesis with help of chlorophyll A and blue pigment phycocyanin.
Phylum Prochlorophyta: These are organisms that contain chlorophyll A and B.
Phylum Schizophyta: These Monera include heterotrophic eubacteria that include different types of bacteria like saprobes and parasites.
Monera Examples
Actinomyces
Bacillus
Bacteroides
Bordetella
Campylobacter
Chlamydia
Clostridium
Corynebacterium
E.coli
Enterobacteriaceae
Haemophilus
Helicobacter
Klebsiella
Legionella
Listeria
Moraxella
Mycoplasma
Neisseria
Nostoc
Prochloron
Proteus
Pseudomonas
Rickettsia
Salmonella
Shigella
Staphylococcus
Streptococcus
Treponema
The kingdom Monera contains organisms with the simplest structures as compared to other kingdoms. They are the first life form to have evolved on planet earth. I hope this article on Monera characteristics has helped you understand the organisms belonging to this animal kingdom classification better.comparison of microbial diseases: with treatment
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