Botany

Micrasterias
fimbriata

BA410

PlanFluar 10x

Moticam 10
Botany

Crystals in
Larix decidua

BA410E

PlanApo 40x
pol. lam.

Moticam 10 stack
Zoology

Parnassius apollo
part of wing

BA310E

PlanApo 20x

Moticam 10 stack
Histology

Femur cross
section

BA310E

PlanApo 20x

Moticam 10
Pathology

Haemolysis
streptococcus
sepsis

BA410

PlanAchro 100x o.i.

Moticam 5
Microbiology

Onion mitosis

BA410 

PlanAchro 60x

Moticam 5
Zoology

Barnacle on
mussel

SMZ-171

Stereo

Moticam 10 stack
General

Tumbled gems

SMZ-171

Stereo

Moticam 10 stack
Pathology

Eimeria stiedae
in liver

BA410 
PlanFluar 20x

Moticam 10
Microbiology

Penicillium with
conidiophores

BA310E

PlanApo

Moticam 10
Histology

Artery

BA410

PlanAchro 10X

Moticam 5
General

Urea crystals

BA410

PlanFluar 20x
pol lam

Moticam 10


Tiny packages that contain all information necessary for life

  • Human chromosomes

Chromosomes are the packages that hold DNA. They play anessential role in genetics; they are the parcels of genetic material that are passed down from parents to children and together contain the full set of inherited instructions that an embryo receives.

Found within the nucleus (the cell's control center), a chromosome consists of tightly coiled DNA wrapped around proteins that give chromosomes their structure. Tinier than a grain of salt,human chromosomes are only between 2 and 10 micrometers in length, but each contains millions of letters of DNA. Each chromosome is like a chapter of a book, brought together, they make up an organism's entire genome and tell a full genetic story.

When a cell divides, it must ensure that both the newly formed cells are given a full set of genetic instructions. As part of this process, the cell's chromosomes, which are otherwise unraveled and diffuse, condense and line up. Researchers can stain these chromosomes and see them through a microscope, stained chromosomes sometimes look like threads with light and dark bands. These bands make it possible to distinguish different chromosomes and line them up to create an organized picture or karyotype.

Human cells contain a total of 46 chromosomes - two sex chromosomes and 22 pairs of non-sex chromosomes. Other species have different numbers of chromosomes and may have more or less than two copies of each. Fruit flies have a mere eight chromosomes, dogs have 78, and goldfish have over 100.



You can find it on rotting fruit

  • 50
  • Rhizopus

Rhizopus is a genus of common saprobic fungi on plants and specialized parasites on animals.They are found on a wide variety of organic substrates, including "mature fruits and vegetables",faeces, jellies, syrups, leather, bread, peanuts and tobacco. Some Rhizopus species areopportunistic agents of human zygomycosis (fungal infection) and can be fatal. Rhizopus infections are also an associated complication of diabetic ketoacidosis. The widespread genuscontains about nine species.

Rhizopus reproduces by vegetative, asexual and sexual methods by spores. The asexualsporangiospores are produced inside a pinhead-like structure, the sporangium, and aregenetically identical to their parent. In Rhizopus, thesporangia are supported by a largeapophysate columella, and the sporangiophores arise amongdistinctive rhizoids. Darkzygospores are produced after two compatible mycelia fuse during sexual reproductionproducing colonies that may be genetically different from their parents.



 

Feulgen stain, still indispensable for microscopic research

  • Bacillus cereus planapo100xmot10

Robert Feulgen (1884–1955) was a German physician and chemist who, in 1914, developed a method for staining DNA (now known as the Feulgen stain) and who discovered that DNA is located in the chromosomes and also discovered plant and animal nuclear DNA ("thymonucleic acid") congeniality.

Feulgen stain is a staining technique in histology to identify chromosomal material or DNA in cell specimens. It depends on acid hydrolysis of DNA, therefore fixating agents using strong acids should be avoided. The specimen is subjected to warm (60 °C) hydrochloric acid, then to Schiff reagent. In the past, a sulphite rinse followed, but this is now considered unnecessary. Optionally, the sample can be counterstained with Light Green SF yellowish. Finally, it is dehydrated with ethanol, cleared with xylene, and mounted in a resinous medium.

Bacillus cereus is a type of bacteria that produces toxins. These toxins can cause two types of illness: one type characterized by diarrhea and the other, called emetic toxin, by nausea and vomiting. These bacteria are present in foods and can multiply quickly at room temperature.


 

Alexander Fleming's discovery

  • Penicillium Plan Apo 10X
  • Penicillium Plan Apo 20X
  • Penicillium Plan Apo 40X

Species of Penicillium are recognized by their dense brush-like spore-bearing structures called penicilli (sing.: penicillus). The conidiophores are simple or branched and are terminated by clusters of flask-shaped phialides. The spores (conidia) are produced in dry chains from the tips of the phialides, with the youngest spore at the base of the chain, and are nearly always green. Branching is an important feature for identifying Penicillium species. Penicillium is a large and difficult genus encountered almost everywhere, and usually the most abundant genus of fungi in soils.

Penicillium chrysogenum is a widely studied species of Penicillium. It plays a significant role in the medical community as an antibiotic because it can create penicillin which inhibits the biosynthesis of bacterial cell walls affecting lysis of the cell. Penicillium was originally discovered by Alexander Fleming. Fleming observed that staphylococcus cultures which had been left on the lab bench and allowed to grow, had begun to lyze and that the active factor could be extracted by filtration of the mold. He described Penicillium as a fungal colony that begins as a “white fluffy mass” that later turns green then black. A yellow colour appears after several days that will diffuse throughout the medium.

 

Simple onions: they teach you a lot!

  • 2 Onion root tip mitosis BA410BFF 100X Moticam 10
  • 1 Onion root tip mitosis BA410 BFF obj. 20X Moticam 2500
  • 3 Onion root tip mitosis BA410BFF 100X Moticam 10
Mitosis: the process where a single cell divides, resulting in generally two identical cells, each containing the same number of chromosomes and genetic content as that of the original cell. Thin slices of the union root tip have been used to teach mitosis and meiosis for decades. Onion Root tip has large cells with clear easy to see chromosomes.

The stages of mitosis:

Interphase
The nucleus is surrounded by the nucleus membrane. It encloses the chromatin network, in which two nucleoli are present.
Prophase 1 and 2
The chromatin network becomes more dense by spiraling, the nucleoli disappear. The chromosomes supercoils and the fibers of the spindle apparatus begin to form. The nuclear membrane also disintegrates at this time, freeing the chromosomes into the surrounding cytoplasm. Some of the fibers attach to the centromere of each pair of sister chromatids and they begin to move toward the center of the cell.
Metaphase
At metaphase the chromosomes have come to rest along the center plane of the cell.
Anaphase 1 and late anaphase
During anaphase, the centromeres split and the sister chromatids created by lengthwise division, begin to migrate generally towards the opposite poles of the cell.
Telophase 1 and 2
During telophase, the chromosomes at either end of the cell  begin to cluster together, which facilitates the formation of a new nuclear membrane. This also is when cytokinesis occurs, leading to two separate cells. One way to identify that telophase has begun is by looking for the formation of the cell plate, the new cell wall forming between the two cells.


 

Walking without legs

  • Amoeba Proteus BA410 Ph obj. 10X Moticam 10

Amoeba proteus gets its name through two Greek words; Amoeba meaning change and proteus  meaning  Sea  God.  The  Greek  meaning  describes  this  microbe  as  the  Sea  God Proteus  that  has  an  ever  changing  shape.  Its  ability  to  change  shape  is  from  the pseudopodia,  which  are  common  in  eukaryotic  microbes.  The  pseudopodia  grants  the microbe an ability to extend and contract into any possible shape.

The Amoeba proteus can be described as unicellular, colorless, or transparent. The average size of an Amoeba proteus varies around from 0.2 to 0.3 mm in diameter but larger forms have been found measuring up to 0.5 mm in diameter which is visible to the eye. Amoeba proteus prefers to habitat clean ponds of highly oxygenated fresh water. It is found in large food webbed ecosystems that contain lots of algae and plants. Since it is adverse to light it will take cover under anything that provides shade, usually lily pads.

Source: Microbe Wiki