Histology: Connective Tissue- Blood Flashcards
What is blood?
A fluid connective tissue that circulates through the cardiovascular system.
What does blood connective tissue consist of?
- plasma (protein-rich liquid extracellular matrix)
- formed elements (white blood cells, red blod cells, and platelets)
What is the name of the protein-rich liquid extracellular matrix?
plasma
What is the composistion of blood?
55% plasma
41% red blood cells
4% white blood cells
0.01% platelets
+ lymphocytes
+ basophils
+ eosinophils
+ monocytes
+ neutrophills
Why is blood an exception to connective tissue?
- it does not have fibers.
- it only has ground substance.
- it is liquid
normally the ECM is a solid substance.
Why are fibers not counted into the ECM?
If there would be fibers in a circulating substances, then it could clot and close the smallest blood vessel blocking circulation, causing a heart attack.
What does plasma consist of?
- albumin
- globulins (immunoglubulins and noimmune globulins)
- fibrinogen
What is albumin in blood plasma responsible for?
colloid osmotic pressure
What are globulins responsible for?
antibodies and immune response
What is fibrinogen responsible for?
blood clotting
What is “serum”?
Blood plasma from which clotting factors have been removed.
What is the difference between plasma and serum.
plasma has clotting factors, while serum does not.
–> serum cannot clot
What are erythrocytes?Describe their structure.
- anucleate
- biconcave discs
- packed with heamoglobin
- designed to withstand shear forces experienced during circulation
What are erythrocytes packed with?
heamoglobin
What are erythrocytes designed to withstand?
shear forces experiences during circulation.
What is the normal life span of erythrocytes? How do they reproduce?
120 days
- due to lack of nucleus, they cannot replicate by themselves, therefore their lifespan is very limited anyways.
- produced in blood marrow by other cells.
What is heamoglobin?
- a specialized protein
- consisting of 4 chains of globins with iron containing heam groups for binding, transporting and releasing O2 and CO2
How does O2 and CO2 bind to red blood cells?
- by heamoglobin
- 4 globin chains
- iron containing heam groups
for transporting, binding and releasing.
What are red blood cells called in mammals?
“disks”
–> anucleate, biconcave disks
Why is the biconcave surface necessary in red blood cells?
it makes the SA:V ratio larger, increasing gas exchange.
–> more effitient in transport of the 2 gases
Do erythrocytes vary between species?
Erythrocytes are very different depending on the type of animal and species they are located within.
What type of erythrocytes exist in mammals?
disks, they are biconcave (no nucleus)
What type of erythrocytes do birds, fish, and reptiles have?
- much large
- elongated
- ‘egg shape’
- oval nucleus
remeber: egg shape - evolved from a dinasour egg
What are the differences in mammals of red blood cells? State examples.
eg. equine (horses) vs canine
equine red blood cells do not have smooth surfaces and are smaller, while canine red blood cells have smooth surfaces and are much larger.
What is the professional name used for “white blood cells”?
leukocytes
What two groups are leukocytes subdivided into? Based on what?
based on the PRESENCE or absense of SPECIFIC GRANULES in the cytoplams.
(a) GRANULOCYTES (neutrophils, eosinophils, basophils)- contain granules
(b) AGRANULOCYTES (lymphocytes, monocytes)- do not contain granules
Which of the following are agranulocytes, and which are granulocytes?
- neutrophils
- basophils
- lymphocytes
- monocytes
- eosinophils
AGRANULOCYTES:
- lymphocytes
- monocytes
GRANULOCYTES:
- neutrophils
- basophils
- eosinophils
agranulocytes: lymo
What type of dye is eosin?
- acidophylic dye
- dyes cytoplasm structures and cytoplasm
- pink colour
What type of dye is hematoxilin?
- stains nucleus
- blue colour
What are the two major types of dye? What colour do they stain? What do they stain?
Hematoxylin- nucleus; blue
Eosin- cytoplasm; pink
What stains eosinophils? In what colour?
eosin, in pink
eosinophil-eosin
What stains basophils? In what colour?
hemotoxilin, in blue
BasophiL- BLue
What stains neutrophils? In what colour?
not stained at all. not associated with stain.
neutrophil-neutral colour
What parts of leukocytes are dyed?
granules!
granules occupy most of cells volume.
Explain neutrophils. What are they classified as? What percentage are they of all leukocytes? What are their nuclei like? What colour are they? What do their granules contain? What is their purpose? What happens once the infection is conquered?
- classification: granulocytes
- percentage: 47%-67% of all leukocytes
- polymorphic, multilobed nuclei
- colour: clear
granules contain various enzymes, complimet activators and antimicrobial peptides.
purpose: destroy microorganisms at sites of inflammation.
(they phagocytize the pathogen causing the infection and stop the infection.)
- neutrophils die after the infection is conquered
neutrophil- i feel “neutral” when i have an infection
What is pus? What is it created from?
yellow-white exudate formed at the site of infection.
consists of:
(1) protein based fluid
(2) dead neutrophils
How many segments are the neutrophil nucleuses made up of?
3 segments
neu-tro-phil
How many segments does the nucleus of eosinophils have?
2 segments (in a ring shape)
2 o
How many segments does the nucleus of basophils have?
2 segments yet the link of segments is in the center.
What is the most common type of granulocytes?
neutrophils
How can one see the infection and work of neutrophils with the naked eye?
through pus
What is the life span of neutrophils?
around 1 week
What is a Barr body? Where is it seen?
- a small segment in the nucleus of neutrophils
- associated with the practical perspective (can distinguish the gender). Barr bodies are only found in female blood.
Explain eosinophils. What are they classified as? What percentage are they of all leukocytes? What are their nuclei like? What colour are they? What do their granules contain? What is their purpose? What happens once the infection is conquered?
- classification: granulocytes
- percentage: 1%-4% of all leukocytes
- polymorphic, bilobed nuclei
- colour: pink
granules contain various proteins that are cytotoxic to protozoans and helminthic paracytes.
purpose: associated with allergic reactions, paracytic infections, and chronic inflammation.
What is the interior of the eosinophil granules cytotoxic to?
- protozoans
- helminthic paracytes
Why can neutrophils not work with paracytes such as worms?
Neutrophils are much smaller than the paracyte. Therefore only the eosinophils can fight them.
How do eosinophils work?
1) go to the site of infection
2) bind to the surface of the paracyte
3) releases its granules (filled with toxic substances)
4) toxic substances from granules kill the paracyte
What is the major difference between granulocytes?
The composition of their granules.
Explain basophils. What are they classified as? What percentage are they of all leukocytes? What are their nuclei like? What colour are they? What do their granules contain? What is their purpose? What happens once the infection is conquered?
- classification: granulocytes
- percentage: <0.5% of all leukocytes
- polymorphic, irregular lobed nuclei.
- colour: blue
granules contain heparine, histamine and other molecules.
purpose: associated with allergic reactions and chronic inflammation.
What is an allergic response?
immunological response against harmless substances (eg. dust, food, etc.)
What is the ‘maximal state’ of allergic reactions called?
anaphylaxis shock
What happens during anaphylaxis shock?
blood vessels makes gaps, causing the liquid part of the blood to leave the tissue.
–> blood pressure decreases,
–> blood circulationn stops.
What is the worst case of anaphylaxis shock?
patient dies in a few minutes
What is histamine related to?
basophylic cells!
Explain lymphocytes. What are they classified as? What percentage are they of all leukocytes? What is their structure? How many major types are there of lymphocytes?
- classification: agranulocytes
- percentage: 26%-28% of all leukocytes
- structure:
(a) vary in size,
(b) dense spherical nuclei,
(c) surrounded by a thin rim of cytoplasm. - types: 3
What are the main functional cells of the immune system?
lymphocytes
What are the three types of lymphocytes? What are their purposes?
1) T- lymphocytes (T-cells; involved in cell-mediated immunity);
2) B-lymphocytes (B cells; involved in humoral immunity);
3) Natural Killer Cells (NK; programmed to kill certain virus infected and cancer cells)
How does the structure of different lymphocytes vary?
it doesnt.
What does ‘humoral immunity’ mean? What type of lymohocytes are associated with humoral immunity?
‘humoral’- liquids
- B-lymphocytes are located in the lymph and blood (liquid)
humour- bombel- liquid
What do B-cells actually do?
- produce antibodies (proteins produced for specific antigens)
- travel in the blood and plasma
What do antibodies do to the virus?
- nothing
- they dont kill or affect the virus
1) antibodies attatch to the surface of the pathogen (antigens) and dont allow the virus to infect the cells.
2) act as indicators that the entire cell should be phagocytized. (attract neutrophils, allowing the pathogen to be digested).
What is oposinozation?
Opsonization is an immune process which uses opsonins to tag foreign pathogens for elimination by phagocytes. Without an opsonin, such as an antibody, the negatively-charged cell walls of the pathogen and phagocyte repel each other.
antibodies produced by B-lymphocytes attatch to antigens of pathogens.
What is ‘cell mediated’ immunity? What type of lymphocytes aid in this?
cell mediated immunity:
(1) when virus infects a cell, the virus is ‘hiding’ within the cell, disabling any antibodies from attathcing to it (as it is not circulating in the liquid (lymph or blood)).
- when a cell is infected by a pathogen, the cells machienery changes, further changing the cells receptors.
- T-lymphocytes checks the receptors of cells
- if the receptor change is detected, then the T-lymphocyte sends out a signal for the cell to die.
- the cell therefore dies together with the ‘hiding’ virus.
Why is the name ‘cell-mediated’ immunity?
the approach of an immune response to antigens which are located WITHIN THE CELL.
Why do diseases occur?
The malfunctioning of some parts of the immune system.
Explain monocytes. What are they classified as? What percentage are they of all leukocytes? What is their structure? What do they transform into, when? What is their function?
- classification: agranulocyte
- percentage: 3%-9% of all leukocytes
- structure: indented nuclei
monocytes transform into macrophages, after migration from the vascular system
FUNCTION:
- engulf and digest cellular debris, foreign substances, microbes, calcer cells
- anti-gen presenting cells (in the immune system)
What is special about monocytes? What happens after they circulate in the blood for an extended time?
- monocytes leave the blood
- enetr a specific tissue
- transform into macrophages
What cells do macrophages originate from?
monocytes
ma-mo
What is the difference between monocytes and macrophages?
monocytes- early stages of cell cycle (circulating in blood vessels
macrophages- later cell-cycle stages (within tissue; phagocytize material)
What is the difference between thrombocytes and platalets?
difference: dependant on the presence of the nucleus and other organelles, yet different names must be used for different animals.
mammals: platalets
birds and reptiles: thrombocytes
What are platalets? What is the 2 words needed to be used to describe their origin?
- small,
- membrane-bounded,
- anucleate,
CYTOPLASMIC FRAGMENTS - derived from megakaryocytes.
What do platalets not have?
- entire cell parts (organelles)
- ie. nucleus, mitochondria, and other organelles
What are thrombocytes?
- nucleated
CELLS - smaller
- less elongated than red blood cells
- large nucleus
What is the fucton of thrombocytes?
similar to the function of platalets in mammals.
