7. unit 2a blood
Post on 07-Apr-2018
225 Views
Preview:
TRANSCRIPT
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 1/26
Unit 2A
Human Form & Function
Body systems
Blood
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 2/26
Study Guide
Read :
•
Text Chapter 9 Complete:
• RQ 1-12
• AYK 5&6
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 3/26
The circulatory system
Blood
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 4/26
Functions of blood
• Transport
•
Transports nutrients, oxygenand hormones to the tissues.
• Removes wastes such as
carbon dioxide and urea.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 5/26
• Regulation
•
Helps to keep the body’s pHwithin its homeostatic range.
• Helps in regulating the body's
temperature.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 6/26
• Protection
•
Prevents blood loss if bloodvessels are damaged.
• Protects the body against
pathogens and toxins.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 7/26
Features of blood
• Temperature 380C
•
pH 7.35-7.45• Salinity 0.9%
• Total body weight 8%
• Volume Men 5-6 L,Women 4-5 L
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 8/26
Composition
~55%~40%
~4%
~1%
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 9/26
Blood plasma
• Plasma is a clear, pale yellow liquid
which comprises 46-63% of the whole
blood• Plasma consists of:
water (92%)
dissolved organic and inorganic solutes
(e.g. sodium & chloride ions, nutrients &wastes) (1%)
dissolved plasma proteins (7%)
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 10/26
Bloodcells
Number/mm3
Principal function
Red bloodcells (Erythro-cytes)
4-6 million Transport of O2 (&some CO2 transport)
White blood cells (Leukocytes)
Granularleukocytes
Neutophils 2 000-7 000 Phagocytes
Eosinophils 100-400 Phagocytes & anti-inflammatory response
Basophils 20-100 Inflammatory response
Agranularleukocytes
Monocytes 100-900 Phagocytes
Lymphocytes 1 500-3 000 Immune response
Platelets (Thrombo-
cytes)
200 000 -500 000
Blood clotting
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 11/26
Formed elements
Red bloodcells
White blood
cells
Bloodplatelets
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 12/26
Red blood cells
EM unit / Royal Free Medical School, Wellcome Images
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 13/26
White blood cells
Neutrophil Basophil
Eosinophil Monocyte
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 14/26
Clotting of blood
David Gregory& Debbie Marshall, Wellcome Images
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 15/26
Clotting of blood
• A blood clot is a jelly-like massthat forms at the site of a wound
to stop bleeding.
• A clot consists of a mesh of long,
stretchy protein fibres, andtrapped blood cells.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 16/26
• When the clot solidifies it formsa scab.
• If a clot forms inside a blood
vessel it forms a thrombus.If a thrombus breaks loose itcan lodge in a vital blood vessel
in the heart or brain causing aheart attack or stroke.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 17/26
The thrombin system
1.Following damage to a blood vessel,blood platelets and the injured cellsrelease thromboplastin.
2. Thromboplastin interacts with Ca ++and prothrombin (an inactive plasmaprotein) to form thrombin.
3.Thrombin converts finbrinogen (another inactive plasma protein) tolong, stretchy fibres of fibrin.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 19/26
Serum is the clear yellow fluid
that oozes out of the clot – thisis plasma minus the fibrinogen.
After a couple of days an enzymein the clot activates fibrinolysis
- this starts the break-down of the clot
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 20/26
The thrombin system - summary
• Thromboplastin +prothrombin + Ca++= thrombin
• Thrombin + fibrinogen = fibrin
• Fibrin + blood cells = clot
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 21/26
The inflammatory response
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 22/26
• Inflammation is the body’sresponse to harmful substances,
injury, or irritants.
• Typically the affected area
becomes red, tender andswollen.
The inflammatory response
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 23/26
Stages in the inflammatory
response
• When the body is injured,
infected or exposed to irritants,radiation, or extremetemperatures, a complex
chemical response is initiated.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 24/26
• This response involves severalcompounds being released in theaffected area. These substancesboth interact and have specificoutcomes (i.e. the inflammatoryresponse)e.g. histamine is released by mastcells, which causes local dilation of
the blood vessels and increasesmucus secretion – anti-histamine drugs reverse this effect.
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 25/26
The inflammatory response
The inflammatory response includes:
• Dilation of the blood vesselsin the affected area.
• Increased permeability of the capillaries, allowingplasma to leak into
surrounding tissue.
• Chemotaxis – phagocytes areattracted to the affected area.
Resulting inredness,swelling,heat & pain
8/3/2019 7. Unit 2A Blood
http://slidepdf.com/reader/full/7-unit-2a-blood 26/26
The inflammatory response
1. Chemical response toinjury
A variety of chemicalsreleased in theaffected area
2. Inflammatory response
•Vasodilation of blood vessels
•Increased permeability ofblood vessels
•Chemotaxis
Site ofinjury
top related