PLASMA PROTEIN

Question 1

Plasma Protein

Answer 1

❖Major solid constituent of the plasma
❖Total plasma protein concentration is
7.4 g/dL (6.4 - 8.3 g/dL)

Question 2

types of plasma protein

Answer 2

Anki

Question 3

Albumin features

Answer 3

• Plasma levels are 4.8 g/dL (range 3–5 g/dL)
• Molecular weight of prealbumin is 60,000 and of albumin is 69,000
• Synthesis - Liver

Question 4

Globulin

Answer 4

• Plasma levels are 2.3 g/dL (range 2 to 3 g/dL).
• Molecular weight varies from 90,000 to 156,000.
• Types include α1, α2, β1, β2 and γ globulins.

Question 5

Fibrinogen

Answer 5

• Plasma levels are 0.3 g/dL.
• Molecular weight is 500,000.
• Synthesized in the liver.

Question 6

Synthesis of Plasma Proteins

Answer 6

embryo- mesenchymal cells
adult- ❖Albumin and fibrinogen - RES (reticuloendothelial system) of liver
❖α & β globulins- liver, spleen and bone
marrow
❖γ globulins- B lymphocytes

Question 7

Functions of Plasma Proteins (11)

Answer 7

Exert Osmotic Pressure
Blood coagulation
Maintain acid-base balance
Role as preserve protein
Fibrinolytic function
Nourishment of tissue cells
Contribution to blood viscosity
Defense mechanism
Transport function
Role in suspension stability of RBCs
Role ingenetic information

Question 8

Exert Osmotic Pressure

Answer 8

-Protein molecules unable to pass caused exert colloid osmotic pressure
❖ Pressure - Important in exchange of water between the blood and tissue fluid

Question 9

Contribution to blood viscosity

Answer 9

❖ Fibrinogen and globulins are significant contributors
❖ The blood viscosity plays an important role in the maintenance of blood pressure→resistance to flow of blood in blood vessels

Question 10

Blood coagulation

Answer 10

❖ The fibrinogen, prothrombin and other coagulation proteins present in the plasma play an important role in the coagulation of blood.

Question 11

Defense mechanism

Answer 11

❖ The γ globulins – antibodies which play an important role in the immune system – against the microorganisms.

Question 12

Maintain acid-base balance

Answer 12

❖ Plasma proteins act as buffers and contribute for about 15% of the buffering capacity of blood.

Question 13

Transport function

Answer 13

❖ Plasma proteins combine easily with many substances and play an essential role in their transport as i.e. carbon dioxide, thyroxine, cortisol, vitamin A, D and Vitamin B12, bilirubin, drugs, calcium & copper

Question 14

Role as preserve protein

Answer 14

❖ Plasma proteins serve as reserve proteins and are utilized by the body tissues during conditions like: Fasting, inadequate protein intake and excessive catabolism of body proteins

Question 15

Role in suspension stability of RBCs

Answer 15

❖ Property of RBCs - remain uniformly suspended in the blood. Globulins and fibrinogen accelerate this property

Question 16

Fibrinolytic function

Answer 16

❖ The enzymes of the fibrinolytic system digest the blood clot (thrombus)

Question 17

Role in genetic information

Answer 17

❖ Many plasma proteins exhibit polymorphism. Polymorphism is a Mendelian trait that exists in the population with differing prevalence.

Question 18

Nourishment of tissue cells

Answer 18

❖ The plasma proteins are utilized by the leucocytes to produce the substances known as trephones or carrel – nourishment of tissue cells

Question 19

Changes of Plasma Protein in Health & Diseases

Answer 19

Anki

Question 20

DESCRIBE Physiological Variations

Answer 20

Infant
The total protein level is low (about 5.5 g/dL) due to low γ globulins.

Old age
There is a tendency for the albumin level to fall and the total globulin level to rise.

Pregnancy
During first 6 months, the albumin and globulin levels decrease while the fibrinogen level increases.

Question 21

DESCRIBE Abnormalities of Plasma Protein

Answer 21

Hypo-proteinaemia
Decrease in the levels of plasma proteins.

Hyper-proteinaemia
Increase in the levels of plasma proteins.

Reversal of normal A/G ratio
* The (A/G) ratio (1.7:1) is reversed in the following conditions:
i. When the albumin synthesis is decreased
ii. When the globulin levels are increased

Question 22

There is pressure between blood vessel and
ECF
Why??

Answer 22

Differences in pressure in the blood pressure and osmotic pressure helps fluids move out of capillaries at the arterial end and into capillaries at the venous end

Question 22

There is pressure between blood vessel and
ECF
Why??

Answer 22

Differences in pressure in the blood pressure and osmotic pressure helps fluids move out of capillaries at the arterial end and into capillaries at the venous end

Question 23

Capillary Fluid Exchange

Answer 23

-When capillary pressure increases, fluid is filtered into the interstitial fluid due to hydrostatic force
-When capillary pressure decreases, fluid is absorbed into the capillary due to oncotic pressure

Question 24

So, what is the role of plasma proteins in starling force

Answer 24

Starling’s forces
Forces that control the movement of fluid in/out of a capillary

Hydrostatic Pressure, P
Pressure exerted by blood (water) on the walls of blood vessel
-13 mmHg filtration pressure

Colloid osmotic (oncotic) Pressure, π
-Pressure created by non-diffusible plasma protein inside the blood vessel
-7 mmHg

-hyperprotein- higher pressure
- hypoprotein- low pressure

Question 25

The Lymphatic System

Answer 25

❖ The lymphatic system – which fluid can flow from the interstitial spaces into the blood.
❖ can carry proteins and large particulate matter away from the tissue spaces
❖ This return of proteins to the blood from the interstitial spaces is an essential function without which we would die within about 24 hours

Question 26

Importance of The Lymphatic System

Answer 26

control:
-The concentration of proteins in the interstitial fluids
-The volume of interstitial fluid
-The interstitial fluid pressure

Question 27

Negative pressure

Answer 27

cause edema- Atypical accumulation of fluid in the interstitial space, leading to tissue swelling