plasma proteins and homeostasis lecture note erk umk
TRANSCRIPT
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SEM I (2011)
FACULTY OF VETERINARY MEDICINEUNIVERSITI MALAYSIA KELANTAN
Week V Lecture (9 October 2011)
Course Coordinator: DR. ERKIHUN AKLILU W.G. (Course Coordinator)
ANIMAL PHYSIOLOGY I
Week V Lecture
PLASMA PROTEINS AND HOMEOSTASIS
Plasma proteins and Homeostasis Introduction A human body is Split Into three Solution-
Filled Compartments
Body 60-80% water by weight 70 kg man has ~ 49 kg water = ~49 litres 3 Main compartments:
Intracellular (inside cells) = ~ 34 liters Interstitial (outside cells) = ~ 13 liters Blood plasma = ~3 liters
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Body FluidsBlood plasma 40% of blood is red blood cells
(RBCs)
Plasma is similar to interstitial fluid, but contains plasma proteins
Serum = plasma with clotting proteins removed
Intracellular fluid is very different from interstitial fluid (high K concentration instead of high Na concentration, for example)
BLOOD
PLASMAComposition of Plasma
Water 90%
Organic substance 9%
Plasma proteins 7% (albumin, globulin, firinogen)
Other organic substance 2% metabolic products urea creatinine,
nutritive substance like Glucose & Amino Acids, Enzymes, hormones,vitamines
Inorganic substance 1% Na, K, Ca, Cl
Respiratory gases O2, CO2
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PLASMA
Plasma ProteinPlasma Protein Functions
Blood coagulation: fibrinogen & prothrombin.
Blood viscosity: 2 times more than water & maintain diastolic bl. Pressure.
Production of an effective osmotic pressure maintaining body fluid
Buffering action.
Defence action. Antibodies are gamma globulins
Carriage of CO2
Regulation of capillary permeability.
Carrier functions: vitamins, Iron, copper, cholesterol, phospholipids, hormones e.g. Thyroxin, cortisol.
Protein metabolism.
HOMEOSTASISHomeostasis
Is the maintenance of a stable internal environment
Describes the physical and chemical parameters that an organism must maintain to allow proper functioning of its component cells, tissues, organs, and organ systems
Enzymes function best when within a certain range of temperature and pH
Cells must strive to maintain a balance between having too much or too little water in relation to their external environment
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HOMEOSTASISThe Internal Environment
There are two types of extracellular fluids in animals:
The extracellular fluid that surrounds and bathes cells
Plasma, the liquid component of the blood.
HOMEOSTASISInternal components of
homeostasis:
Concentration of oxygen and carbon dioxide
pH of the internal environment
Concentration of nutrients and waste products
Concentration of salt and other electrolytes
Volume and pressure of extracellular fluid
HOMEOSTASIS
Stages in homeostasis
Detection: A receptordetects the changes from the stable state
Counteraction: An effector counteracts the changes from the stable state
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HOMEOSTASIS
Three (3) main components:
a. Receptor (receives a stimuli: detection)
b. Integrator (processes the information from the stimuli) --"regulatory centre“
c. Effector (carries out a response to the stimuli: counteraction)
HOMEOSTASISMechanisms of homeostasis
Two (2) different mechanisms (body responses):
Negative feedback: cancels or counteracts original stimuluse.g., blood sugar balance, blood pH balance, blood pressure balance, body temperature
Positive feedback: increases original stimulus [e.g. child birth (labor), sexual reproduction (orgasm)]
Most homeostatic mechanisms operate by negative feedback
Blood GlucoseBlood Glucose The amount of glucose in the
blood is carefully controlled
It is under the hormonal controlsystem
The hormones responsible forregulating blood glucose areproduced in the pancreas inparticular, islets of Langerhans
Blood ion concentrations slightlytoo high or too low can be lethal
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Blood Glucose
Exercise
Glucose is being used up
Alpha cells will produce glucagon
Release of an enzyme that breaks glycogen to glucose
(glycogenolysis)
Blood GlucoseMeal
The blood glucose levels will begin to rise
Pancreatic beta cells, will produce more insulin
Insulin then binds to receptor proteins in cell membranes
(Liver)
More channels open so that more glucose can enter the
cell
Encourages enzymes toconvert glucose to glycogen(glycogenesis) for storage
Blood Glucose
Blood Glucose
Regulation
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HOMEOSTASIS
HOMEOSTASIS
New folder\Homeostasis.mp4
New folder\Homeostasis And Negative Feedback.flv
New folder\Positive and Negative Feedback Loops.mp4