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
The retina, a bio-chip on the back of the eye.
  • retina mammal pap20x mot10
  • retina mammal pap100x mot10

The structure of the eyes is in its basic form the same for all mammals. The function and operation of the eyes of mammals is thus also broadly similar.

The retina which is located on the back of the eye, is composed of very closely spaced light-sensitive cells that are in connection with the brains via the optic nerve. The light signals that reach the light-sensitive cells, are transferred to the brains via the optic nerve. The brains takes these signals and translates them into the picture what is happening before our eyes.


Colors make us distinguish things around us better. But how do our eyes recognize colors and can animals observe different colors as well? The electromagnetic waves from the visible range are of different lengths. The longer waves are perceived by our eyes as red and orange, the shorter ones as green and blue. The light-sensitive cells of the retina consist of two types, rods and cones. The rods cannot distinguish color, but are on the other hand light sensitive and also detect very small light intensities. The cones do convert the received wavelengths in colors. Some mammals, in particular primates, have three different kinds of cones. One is sensitive to blue, the second is sensitive to green, and the third cone is sensitive to yellow-green and red. The brains process them into multicolored images. The cones can only process the colors when light is strong enough. That's why at night everything is seen in gray tones. Maybe it's because of that, it has long been assumed that animals that are active at night, like cats, could not recognize colors. We now know that all mammals are able to see colors to some extent.




Extremely tiny but very useful‘hair’

  • ciliated epithelium planapotk
  • ciliated epithelium planapot

Ciliated epithelium is a type of bodily tissue that is lined with “ciliated” cells, which are basicallycells that have small, hair-like protrusions known as “cilia” that can either help the cells movealong the tissue or can help debris and waste move along the surface of the cells. Cilia typicallymove in one direction in a wavelike pattern, which allows the cells to sweep away debris, directthe flow of particles, and create a current. Tissues in this category are most common in thenasal and respiratory passageways, and are one of the main reasons mucus flows and carriesout dead cells when a person has a cold. They occur in many places, though, including thebrain, digestive system, and reproductive tract. Scientists usually categorize this sort ofepithelium based on where exactly it is, as well as its main function.

Source: wiseGEEK


Red human blood cells in dark field illumination

  • Human red blood cells BA410E planapo20x

In  bright  field  illumination  red  blood  cells  do  not  show  a  strong  contrast.  Staining  is  a  way  to overcome it. Dark field microscopy is another way to increase contrast. I is realized in a normal light  microscope  equipped  with  a  special  so-called  dark  field  condenser,  which  prevents  light passing through the lens, creating a dark field,  unless light it is scattered by red blood cells (or anything else) present in the preparation.

The  red  blood  cells  in  the  blood  bind  oxygen  to  the  red  blood  pigment  (= hemoglobin)  which they contain. In this manner, the oxygen from the lungs is transported to all parts of the body (= oxygen  transport).  The  blood  contains  about  4-5  billion  (!)  Red  blood  cells  per  ml.  Red  blood cells  are  always  prepared  fresh in  the  red  bone  marrow,  by  division  of  certain  bone  marrow stem cells (= erythroblasts).

The blood contains three different types of cells:
Red blood cells.
White  blood  cells  (=  leukocytes)  are  closely  involved  in  the  immune  response  of  the  body against infection by micro-organisms (including bacteria, viruses and fungi).
Platelets  (=  thrombocytes)  initiate  theblood  coagulation thatstops  the bleeding after  a damage.

It's safe stay under your skull

  • Skullcap cross section SZM 171 Moticam 2500

The type of  most bones  of  the human  skull  is flat  bone.  Flat  bones are bones  whose  principle function   is   either  extensive   protection  or   the   provision  of   broad   surfaces   for   muscular attachment.  These  bones  are  expanded  into  broad,  flat  plates,  as  in  the  cranium  (skull),  the ilium (pelvis), sternum and the rib cage.

In the cranial bones, the layers of compact tissue are familiarly known as the tables of the skull; the outer  one  is  thick and  tough;  the  inner  is  thin,  dense,  and  brittle,  and hence  is  termed  the vitreous table. The flat bones in the skull are firmly connected to each other by means of seams.

Flat  bones  are  composed  of  two  layers  of  compact  bone  enclosing  between  them  a  variable quantity  of  cancellous  bone,
which  is  the  location  of  red  bone  marrow.  In  an  adult,  most  red blood  cells are formed  in  the  marrow of flat  bones. This
intervening  cancellous  tissue  is  called the diploë, a spongy bone structure.

Geographically, the bones of the skull can be divided into two parts. The part that protects the brains is called the cranium.
Its primary purpose is to protect the brain. The part that forms the face is called the facial skull.

'No sweat'

  • sweat glands ba410eplanapo40xmot10 x
  • sweat glands ba410eplanapo20xmot10 x

Sweat glands are located all over the body in the skin. In some places they are relatively common. Thus one finds about 300 sweat glands in 1 cm² of the skin of the palm, and on the back only 50. They are located in the lower layer of the dermis. The ducts of the sweat glands open out on the surface of the cuticle (epidermis). At the basis of the sweat glands lie, in a circle, muscle cells between the gland cells. Because of the contraction of the muscles the gland secretion, sweat, is pressed out. Sweat glands have a special form of secretion. They deliver a portion of the cell as secretion. As a result, the cell becomes smaller. After a subsequent growth phase secretion is again possible.

At a normal temperature the body separates 300 to 500 ml of sweat per day. At high temperatures and physical exertion it is a multiple thereof. Perspiration is controlled by the autonomic nervous system and hormones. Increased sweating is not only a result of temperature fluctuations, but also from nervousness and hormonal changes, for example in women in transition. The sweat secretion plays an important role in the heat balance of the organism.

For the evaporation of water heat energy is needed. Evaporation of sweat consumes this energy, leading  to cooling of the body. The main objective of this process is to keep up the normal body temperature, i.e., about 37 ° C.


 

Have a look in your thigh bone

  • Femur cross section BA310E planapo20XMot10
  • Femur cross section BA310E planapo40XMot10
The femur, or thigh bone, is the longest, heaviest, and strongest bone in the entire human body. All of the body’s weight is supported by the femurs during many activities, such as running, jumping, walking, and standing. Extreme forces also act upon the femur thanks to the strength of the muscles of the hip and thigh that act on the femur to move the leg. The femur is classified structurally as a long bone and is a major component of the appendicular skeleton.

Bone is living tissue and has a hard, relatively rigid matrix. The matrix contains numerous collagen  fibres  and  is  impregnated  with  inorganic  salts,  primarily  calcium  phosphate. Compact bone is composed of numerous structural units called Haversian systems. Each Haversian system is seen as a nearly round area. The circular core of each system is the Haversian  canal  that  runs  lengthwise  through  the  bone.  Blood  vessels  and  nerves  run through  the  Haversian  canals.  Around  the  Haversian canal is  a  series  of  concentrically arranged hard lamellae, perforated by elongate dark areas, called lacunae, in which the bone cells (osteocytes) are located. The numerous very thin dark lines running radially from the central canal across the lamellae to the lacunae are the canaliculi. These channels connect the bone cells to one another and to the Haversian canal. They provide the "highways" through which tissue fluid, oxygen, and nutrients can reach the widely separated bone cells, imprisoned as they are in a desert of solid matrix.


 

Prostate

  • Prostate BA310EPh2 20XMot10
  • Prostate BA410BFF10XMot10
The prostate gland is shaped like a donut, weighs about an ounce and is the size of a chestnut. It consists 30% muscular tissue and 70% glandular tissue.

The prostate gland is just below the bladder, behind the pubic bone and just in front of the rectum. The prostate wraps around the urethra, which is the tube that carries urine from the bladder to the penis.

The prostate helps to control the flow of urine. During sexual activity, the seminal vesicles that are attached to the prostate produce a protein that mixes with prostatic fluid which forms semen. The tubes from the testicles carry sperm up to the prostate where sperm is mixed with the seminal vesicle and prostatic fluids. This fluid is ejaculated during orgasm through ejaculatory ducts that connect to the urethra.

Most men will experience some type of prostate problem during their lifetime. Men over forty-five may experience an enlargement of the prostate. While not a problem in itself, it is uncomfortable and can lead to more serious problems.

The prostate actually continues to grow throughout life, but grows very slowly after the age of twenty-five. Enlargement of the prostate gland is part of the normal aging process and usually does not become a serious problem until about age sixty.

Source: Prostate health network


 

Smoking

  • Lung healthy BA410 BFF obj. 10X Moticam 2500
  • Lung smokers BA410 BFF obj. 10X Moticam 2500
Lung  cancer  is  the  most  common  form  of  cancer  caused  by  smoking.  More  than  80%  of cases of lung cancer are due to smoking. Cigarette smoke contains many chemicals that interfere with the body's method of filtering air and  cleaning  out  the  lungs.  The  smoke  irritates  the  lungs  and  leads  to  overproduction  of mucus. It also paralyses the cilia - tiny hair-like structures that line the airways and clean out dust and dirt. Paralysis of the cilia means mucus and toxic substances accumulate, resulting in congestion of the lungs. This extra mucus means smokers are more likely to suffer from chronic bronchitis and what is known as 'smoker's cough'. Cigarette  smoke  is  one  of  the  best  known  triggers  of  asthma.  When  people  suffer  from asthma  their  inflamed  air  passages,  which  are  very sensitive,  narrow  when  exposed  to cigarette smoke. This causes an asthma attack. Long term exposure of the lungs to the irritants in tobacco smoke destroys the normal lung structure.  The  elastic  walls  of  the  small  airways  within  the  lungs  are  broken  down.  This reduces  the  amount  of  lung  tissue  available  for  the  transfer  of  oxygen  from  the  air  to  the blood. This condition is called emphysema. Some degree of emphysema is found in almost all  people  who  are  long-term  smokers,  however  the  severity  will  vary  depending  on  the amount of cigarettes smoked, and the number of years the individual smokes. Damage  to  the  lung  tissue  is  irreversible.  Emphysema  can  be  prevented  by  not  smoking, avoiding anything that will irritate the lungs such as dust and cold air, and ensuring any chest infections such as flu and bronchitis are treated properly.

Source: Quit org. au.


 

Hair? Where?

  • Skin head cross section BA410 BFF obj. 20X Moticam 10
True  hair  is  found  only  in  the  Class  Mammalia,  and there  is  really  no  such  thing  as  an absolutely  hairless  mammal.  Even  whales  (at  least  some  of  them)  have  rudimentary  hairs here and there. Some other animals have hair-like structures, but if you have real hair, you're a mammal. 

Hair  serves  many functions.  The  most obvious  is to serve  as  insulation,  but  it's  also used  to provide  camouflage  (for  example,  the  spot  pattern  on  a  fawn  deer  mimics  the  play  of  light and shade on a forest floor), for sex recognition (male mammals often have ruffs, manes, or beards  as  secondary  sex  characteristics)  and  even for  social  purposes,  such  as aggressive display (as when a dog's "hackles rise" or a cat elevates her fur on the approach of a dog).

Hair grows from  the hair follicle, not out of it. One  point that needs to  be  emphasized is that the  hair  follicle  and  the  hair  it  produces  are  part  of  the  epidermal  region  of  the  skin.  The follicle  is  separated  from  the  underlying  dermis  and  hypodermis  by  a  basement  membrane, and the hair itself grows from the germinal epithelium at the deepest part of an active follicle. Hairs don't grow "through" the skin. They grow from skin and in a very real sense they're part of the keratinizing system of the epidermal layer.

Reference: Dr. Thomas Caceci