Biology
/ Lecture 1 /
-Visualization technique
- Cell and tissue definiton
Important notes:
Biology LECTURES – will be each week at 16:20. Only 28-9-
2021 is state hliday (however the presentation „Mebranes and
organelss“ will be sent to your email or IS.MUNI profile)
Biology LAB EXCERSISE – will be each second week, the
protocols will e avaluated and you must have credits from
each protocol. If somebody is ill in some week, the extra
excersise will be prepared in December.
Today presentation (for day 21-9-2021) is focused to BASIC
DEFINTION OF CELL BIOLOGY and BASIC OVERVIEW of
Visualization technique in Medicine
What is visibility?
And what visibility is needed in medicine? :
If we fight against “forest disaster“, sometimes we need technique for
macroscopic visibility, sometimes for detail (microscopic) visibility
Analogy:
Good objective visualisation = key step for good fighting
What is visibility?
And what visibility is needed in medicine? :
If we fight against “medical disaster“, sometimes we need technique
for macroscopic visibility, sometimes for detail (microscopic) visibility
Analogy:
Good objective visualisation = key step for good fighting
The human and animal body is not o „bag of sugar water with smal soul inside“, however exact description of body
and tissue structure had to wait to first „science-man“ Aristotle (384–322 BC). Before Aristotle, many Greek
philosophers had speculated copartments of body and live organims but their theorizing was unsupported by
empirical investigation.
We can divide the technique via the invasivity or the non-invasivity:
Homework: 1) ad resolution to your exercisebook (information are on folloving pages)
2) describe basic components of optical microscopy.
Each technique have some advantages
and disadvantages:
For example Hematoma of leg
For medical and pharmacologica curative strategy we need mostly
combination of all these technique.
Looking to the tissue structure by microscopy is the similar problem
like “visualisation“ of paving stone by blind man
We need identify where is the border of paving stone or cells (or
another biological entities)
Ad. Optical and Electron MICROSCOPY
Basic tools for visualisation = fotons (light) and electron (particle)
Basic definition for diferent form of light, which are important for
scinceman in microscopy:
Two important aspect of microscopy visualisation:
MAGNIFICATION and RESOLUTION
May be you know the theory from high school. Who not. There is very
clear definiton: https://www.youtube.com/watch?v=CVusz4wHaic
High resolution = ther is visibility of two leaflet
Low resolution = there is not, two leaflet seems
like one violet flag
Basic construction of microscopies:
OPTICAL and ELECTRON
Resolution
Magnific.
MAGNIFICATION Object RESOLUTION
How we can upgrade some structure of cells for better contrast ?
Use staining.
1) Traditional Histochemistry Staining (used chemicals which
have specific afinity to
some part of cell or
tissue, for example DNA,
collagen etc.
2) Anitibody staining (best way: rimary and secondar antibody
which makes some structure fluorescent)
3) Variety of staining for Electron
microscopy (mostly heavy metal
like Osmium)
Exmple of final photo by optical microscope. Multicolor
image (fluorescence microscopy of fluorsent probe
adhered to specific part of neuron cells)
Most of the microscopy scan needs separation of sample from live
body. However thera are also futuristic and very modern machine ,
for example INTRAVITAL MICROSCOPY:
High Resolution Intravital
Imaging of the Renal Immune
Response to Injury and Infection
in Mice
John Sedin
Ad. FLOW-CYTOMETRY
Good ilustrative video:
https://www.youtube.com/watch?v=B2zreF2dnWk
Flow cytometry is a technology that provides rapid multi-parametric
analysis of single cells in solution. Flow cytometers have started be
used in hematology to speed analysis of blood cells and analysis of
surface protein on these cells
Ad. X-RAY and MRI TOMOGRAPHY
People have only one visibility detector – eye. Half a century
ago, the light was only detecting tool for all doctors and biology
spcialist. However visualisation of some animal and some
machine is based on another electromagnetic :
Infra red
X-RAY CT and also MRI have only grey scale output. We can
say that each milimeter of tissue is precomputed to one pixel
(whit, grey or black). So microscopy has variety of color and
resolution of cells ant biological entities could be higher thanks
to specific staining, on the oposite the CT has contrast which
correlates to „DENSITY OF MATERIAL“ (bones – the highest
density, air – the lowest), MRI has contrast which correlates to
H2O concentration in the tissue (bone – low concentration, soft
tissue – higher concentration). For aditive contrast we use for
example stining of intestine or blood by metal nanoparticles.
X-RAY CT MRI
https://www.youtube.com/watch?v=aQZ8tTZnQ8A
https://www.youtube.com/watch?v=VnpqylFYtqI
CT and MRI are very sofistic technical aparature, where
geat physical theoretic backround is neded from quantm
physics and nuclear physics theory. Very ilustrative
videos for medical and biological worker is here:
CT image quality and
MRI basic principles and resolution
https://www.youtube.com/watch?v=qsHTrQ0lb2s
https://www.youtube.com/watch?v=Ok9ILIYzmaY
MRI
High resolution vs. Bad resolution
Nowadays, most MRI scanners used
for medical purposes have B0 values
of 1.5 or 3 T and can reach typical
resolutions of around 1.5×1.5×4 mm.
In parallel, ultra-high magnetic field
MRI scanners with B0 = 11.7 T are
developed for research pur- pose and
resolutions of 80 × 80 × 200 μm
X-RAY CT
The spatial resolution of CT is
excellent and the primary
strength of the modality. Current
CT scanners have a spatial
resolution of 0.5–0.625 mm in
the z-axis, and approximately
0.5 mm in the x- to y-axes
?
Detail
literature:
CELLS and CELL BIOLOGY
Cells are the fundamental units of life. Thus it is to cell biology—
the study of cells and their structure, function, and behavior—that
we must look for an answer to the question of what life is and how it
Works.
Medicinal experts should have good overview not only about human
cells, but alo about another historical cells and viruses, becouse
their interaction with human body is cccritical development of many
pathologies (flu, diabetic wound, pathology of intestine microorganism,
…aerobic or anearobic environment could induce different
bacterial aktivity etc)
Prokaryotes Eukaryotes
The Prokaryotic CellOf all the types of cells revealed by the microscope, bacteria have the simplest
structure and come closest to showing us life stripped down to its
essentials. Indeed, a bacterium contains essentially no organelles—not
even a nucleus to hold its DNA. This property—the presence or absence
of a nucleus—is used as the basis for a simple but fundamental classification
of all living things. Organisms whose cells have a nucleus are called
eukaryotes (from the Greek words eu, meaning “well” or “truly,” and
karyon, a “kernel” or “nucleus”). Organisms whose cells do not have a
nucleus are called prokaryotes (from pro, meaning “before”).
The Eukaryotic CellEukaryotic cells, in general, are bigger and more elaborate than bacteria
and archaea. Some live independent lives as single-celled organisms,
such as amoebae and yeasts (Figure 1–13); others live in multicellular
assemblies. All of the more complex multicellular organisms—including
plants, animals, and fungi—are formed from eukaryotic cells.
By definition, all eukaryotic cells have a nucleus. But possession of
a nucleus goes hand-in-hand with possession of a variety of other
organelles,
Notes to relationship
of Prokaryotic and
Eukaryotic
….Schematic
comparison of
selected theories for
eukaryote origin.
Details in
Symbiogenesis, gradualism, and
mitochondrial energy in eukaryote origin
September 2017
Periodicum Biologorum 119(3)
Cells vary enormously in appearance
and Function
However biologist during centruries of
modern science made basic
identification of basal cell principles:
Fundamental principles of all known cells are:
(A) CEHMICAL MACROMOLECULES and STRUCTURE
(B) BIOENERGETIC
Essential Concepts
• Cells are the fundamental units of life. All present-day cells are
believed to have evolved from an ancestral cell that existed more
than 3 billion years ago.
• All cells are enclosed by a plasma membrane, which separates the
inside of the cell from its environment.
• All cells contain DNA as a store of genetic information and use it to
guide the synthesis of RNA molecules and proteins.
• Cells in a multicellular organism, though they all contain the same
DNA, can be very different. They turn on different sets of genes
according to their developmental history and to signals they receive
from their environment.
• Animal and plant cells are typically 5–20 μm in diameter and can be
seen with a light microscope, which also reveals some of their internal
components, including the larger organelles.c
The electron microscope reveals even the smallest organelles, but
specimens require elaborate preparation and cannot be viewed
whilealive.
• Specific large molecules can be located in fixed or living cells with
a fluorescence microscope.
• The simplest of present-day living cells are prokaryotes: although
they contain DNA, they lack a nucleus and other organelles and
probably
resemble most closely the ancestral cell.
• Different species of prokaryotes are diverse in their chemical
capabilities and inhabit an amazingly wide range of habitats. Two
fundamental evolutionary subdivisions are recognized: bacteria and
archaea.
• Eukaryotic cells possess a nucleus and other organelles not found
in prokaryotes. They probably evolved in a series of stages,
including the acquisition of mitochondria by engulfment of aerobic
bacteria and (for plant cells) the acquisition of chloroplasts by
engulfment of photosynthetic bacteria.
• The nucleus contains the genetic information of the eukaryotic
organism, stored in DNA molecules.
• The cytoplasm includes all of the cell’s contents outside the nucleus
and contains a variety of membrane-enclosed organelles with specialized
functions: mitochondria carry out the final oxidation of food
molecules; in plant cells, chloroplasts perform photosynthesis; the
endoplasmic reticulum and the Golgi apparatus synthesize complex
molecules for export from the cell and for insertion in cell membranes;
lysosomes digest large molecules.
• Outside the membrane-enclosed organelles in the cytoplasm is the
cytosol, a very concentrated mixture of large and small molecules
that carry out many essential biochemical processes.
• The cytoskeleton is composed of protein filaments that extend
throughout the cytoplasm and are responsible for cell shape and
movement and for the transport of organelles and other large molecular
complexes from one location to another.
• Free-living, single-celled eukaryotic microorganisms are complex
cells that can swim, mate, hunt, and devour other microorganisms.
• Animals, plants, and some fungi consist of diverse eukaryotic cell
types, all derived from a single fertilized egg cell; the number of such
cells cooperating to form a large multicellular organism such as a
human runs into thousands of billions.
• Biologists have chosen a small number of model
Conclusion:
Key terms, which everybody had to understand from actual
lection of Biology