Physiology No 4

‫بســـم الله الرحمن الرحيم‬

‫المحاضرة‬ ‫الرابعة‬ ‫من صـــفحة ‪ 59‬الى صــفحة‬ ‫‪74‬‬

1- Blood returns from the systemic circulation to the right atrium of the heart by two large veins(superior) …………………………………………….and anterior vena cava posterior (inferior) vena ……………………………… . cava

2- Transamination is a metabolic process at which the amino group keto to ……… acid and such process of an amino acid is transfers nonessentia provides the basis of the formation of ………………… amino acids. l 3- As compared to the resting state, vigorously contracting acidof ………………………….. muscles shows an increase in thepyruvic conversion lactic acid (pyruvate) …. to …………………. 4- The sequence of chemical reactions that are responsible for the glycolysis is: glucose + ADP 2 …….. + 2P-3 → 2 pyruvateATP + 2 …… + 4H+. …………… Vitamin E is soluble in -5 ……. and it’s deficiency leads to fats . ..………… sterility and muscular dystrophy and

..……………………… trypsin 6- * Chymotrypsinogen. ..……………………… * Emulsified fat .Pancreatic lipase monoglycerides

chymotrypsin fatty acids +

7- Competitive inhibitor of an enzyme is attached to …………………… active sites a position other than the active ……. while non competitive is attached to ……………………………… site 8- Pancreatic juice contains some enzymes for protein digestion

like …………………………………………………………………. On the other trypsin or chymotrypsin or carboxypolypeptidase hand, saliva digests starch into lactose by (salivary the action of ……………… amylase (ptyalin ………. enzyme. (SAby (sinoatrial 9- The heart beat is normally regulated …………………. node and this node is embeddedright in the ……………… wall. atrial or glucagon Elevated level of circulatingadrenaline -10……………………………… hormone .usually leads to rise blood glucose level ……………………… An example of the non essential amino acids is -11 alanine,, asparagine .… Aspartate, cysteine, glutamate, glutamine, glycine, proline, serineor tyrosine

‫قطعة‬ ‫التمرينات القصوى‬ ‫المساريقا‬ ‫النتشار‬ ‫الضغط السموزى‬ ‫المـﺫاب‬ ‫النفايات‬ ‫سائل النسيج‬ ‫الكتاف أو المناكب‬ ‫أوعية لبنية (موجودة فى خملت المعاء)‬ ‫عقد ليمفاوية‬ ‫أوعية ليمفاوية متوسطة الحجم‬ ‫محاربة العدوى‬ ‫نخاع العظم‬ ‫نسيج ليمفاوى‬ ‫خليا ليمفاوية‬ ‫متباينة أو مختلفة‬

‫‪A piece‬‬ ‫‪Maximal exercise‬‬ ‫‪Mesenteries‬‬ ‫‪Diffusion‬‬ ‫‪Osmotic pressure‬‬ ‫‪Solutes‬‬ ‫‪Wastes‬‬ ‫‪Tissue fluid‬‬ ‫‪Shoulders‬‬ ‫‪lacteals‬‬ ‫‪Lymph nodes‬‬ ‫‪Medium-sized lymph vessels‬‬ ‫‪Fight infection‬‬ ‫‪Bone marrow‬‬ ‫‪Lymphoid tissue‬‬ ‫‪Lymphocytes‬‬ ‫‪Vaned‬‬

Capillary exchange * A piece of muscle of 1mm2 may contain more than 3000 open capillaries during maximal exercise. * Blood flows very slowly through capillaries because the crosssectional area of capillaries is so large as compared to the arterioles. * So, this allows adequate time for exchange of materials between blood and tissue fluid. * Much of this exchange occurs by diffusion through thin capillary wall. * There are 2 forces which control movement of fluid through capillary wall which are osmotic pressure & blood pressure. * The osmotic pressure tends to cause H2O to move to blood while blood to cause to move to tissue 2Oconstant Notes:pressure Osmotic tends pressure whichHis = 25 mm fluid. Hg. Blood pressure at arteriole end = 40 mm Hg. Blood pressure at venule end = 10 mm Hg. So,at the arteriole end, blood pressure is higher than osmotic .pressure → fluid go out through capillary wall At themidway along the capillary, the 2 forces are equal and so .there is no net movement of water At the venule end of a capillary, the osmotic pressure is high, .water ends to move into the capillary

Capillary exchange (continue) Solutes diffuse according to the concentration gradient where nutrients diffuse out of the capillaries while wastes diffuse into the capillaries. There is always some excess tissue fluid collected by the lymph capillaries.

Water O2 Glucose

Capillary exchange

Water Ammonia CO2

The human lymphatic system

A lymphatic vessel & capillary

A lymph node

The human lymphatic system The lymphatic system is a one way system and contains lymph veins (vessel) & capillaries only. It begins with lymph capillaries that found near blood capillaries which take up any excess tissue fluid. Once tissue fluid enter lymph capillaries, it is called lymph. Lymph moves through lymph vessels by the contraction of skeletal muscles near the vessels & by the aid of valves. So, lymph vessels are similar to the cardiovascular veins. . Lymph capillaries → smaller lymph vessels → larger vessels → major lymph duct → blood circulatory veins of the shoulder near the heart. Functions of the lymph: 1) It returns fluids from the tissues to the blood circulatory system. 2) It carries products of fat digestion to the circulatory system via lacteals that present within the intestinal villi. 3) It filters and traps bacteria and other debris through lymph nodes which occur at the junction of medium-sized lymph vessels. This is due to the presence of lymphocytes in these lymph nodes.

Human blood Blood

Function

Source

1- Cells Red blood cells White blood cells Platelets

Transport oxygen Fight infection Clotting

Bone marrow Bone marrow and lymphoid tissues Bone marrow

Maintains blood volume & transports molecules Maintains blood osmotic pressure & pH Transport Clotting Fight infection

Absorbed from intestine

Cellular respiration End product of metabolism

Lungs Tissues

Food for cells

Absorbed from intestinal villi

Maintain blood osmotic pressure and pH. Aid metabolism

Absorbed from intestinal villi

6- Wastes Urea& ammonia

End products of metabolism

Tissues

7- Hormones, vitamins, .. etc.

Aid metabolism

Vaned

2- Plasma Water Proteins Albumin Fibrinogen Globulins

Liver Liver Lymphocytes

3- Gases Oxygen Carbon dioxide 4- Nutrients Glucose, amino acids, fats,… etc. 5- Salts

Types of blood cells 1- Red blood cells (RBCs) (erythrocytes) 2- White blood cells (WBCS) (leukocytes) 3- Blood platelets (thrombocytes) Erythrocytes areso small (5 millions/mm3 ),without cellular organelles .(even nuclei, with hemoglobin (Hb Hb + O2 Oxyhemoglobin Oxygenated blood, carrying oxyhemoglobin, takes on a bright red color which found in pulmonary veins & systemic arteries. Deoxygenated blood carries reduced Hb where the blood is a darker & more purplish color which found in pulmonary arteries & systemic veins. * RBCs are manufactured in red bone marrow (2-3 millions/sec.). * RBCs live about 120 days (4 months) and damaged RBCs are withdrawn to the liver or spleen. RBC Hb Fe (returned to red bone marrow for reuse) + Heme Chemical degradation Heme Bile pigments (excreted by liver which are responsible for

the color of feces)

Anemia results from a fewer number of RBCs as a result of a failure in the balance of erythrocyte production and destruction (or may be due to a lower Hb content in RBCs).

WBCs are usually larger, each has a nucleus, appear white in color without staining. There are two types: A- Granulocytes: Which have 3 types which are: 1- Eosinophils (acidophils). 2- Basophils. 3- Neutrophils. B- Agranulocytes: Which have 2 types which are: 1- Monocytes. 2- Lymphocytes.

When bacteria or viruses enter the body by way of a cut: a) A response called the inflammatory reaction occurs * Damaged tissues (+ basophils & mast cells which found surrounding blood capillaries) → release chemotactic substances e.g. kinins (→ vasodilation) & histamines (→ increased capillary permeability). * Amoeboid neutrophils squeeze through capillary wall then they phagocytize foreign materials. N.B. Thick yellow fluid pus contains a large proportion of dead neutrophils. * Monocytes → macrophages which engulf materials. * Eosinophils become active for cleaning allergic products.

b) Production of antibodies (globulin proteins) by lymphocytes: * It takes place when bacteria or viruses still present in the body. * Each lymphocyte produces just one type of antibody, which is specific for one type of antigen. N.B. Antigens are most often proteins or polysaccharides which found in the outer covering of a parasite or in its toxin. * Antibodies + their antigens → antigens become harmless. This is the basis of immunity.

Cells in normal human blood Component

Number )/mm3 of blood(

Function

Erythrocytes )RBCs(

~ 5 millions

Transports of O2

Leukocytes )WBCs(

7,000 – 8,000

For defense

Thrombocytes )Blood platelets(

200,000 – 400,000

Blood clotting

NB: Blood platelets are fragments of bone marrow cells called megakarycytes.

Cells in normal human blood WBC types

(continue)

Percentage (%)

Function

Granular leukocytes 12- Neutrophils Basophils

60 -70

Phagocytosis

0.5 - 1

3- Eosinophils

2-4

Produce allergic materials Clean allergic products

33 - 20

For immunity

7-4

Become macrophages

Agranular leukocytes 1- Lymphocytes Monocytes -2

Blood clotting (coagulation) The liquidity of blood can cause serious problems when a blood vessel is injured or cut. Clots form temporary barriers to blood loss until a vessel’s wall .has healed 1When a blood vessel is injured, blood platelets begin to aggregate near the injury forming a barrier known as the platelet

plug.

2- When platelets come into contact with an injured vascular wall, they swell up, becomes sticky and release certain chemicals. Note: Some of these chemicals stimulate the blood vessels to constrict, increase the tendency of platelets to form a plug & initiate the process of blood clotting.

Mechanism of blood coagulation Rupture of the cells (extrinsic) Prothrombin Damage of blood (platelets) activator (intrinsic) Prothrombin activator Prothrombi Thrombin (enzyme) n Calcium ions (Ca++) Fibrinogen Loose fibrin threads

Thrombin Calcium ions (Ca++) Factor XIII (plasma protein)

Loose fibrin threads Stabilized fibrin threads

Notes: * Prothrombin & fibrinogen are plasma proteins formed by the liver. * Vitamin K is required by the liver for normal formation of prothrombin & other clotting factors. * The clot is composed of a meshwork of fibrin threads running in all directions and entrapping blood cells, platelets & plasma. * The fibrin threads adhere to damaged surfaces of blood vessels, therefore, the blood clot prevents blood loss.

Clot retraction - serum * After a clot is formed, it begins to contract and expresses most of the fluid from the clot within 20 – 60 minutes. * The fluid expressed is called serum. * So, Serum = Plasma - Fibrinogen & most of the other clotting factors In other words, Plasma = Serum + Fibrinogen & most of the other clotting factors

Blood typing No.

System name

System symbol

Gene name(s)*

Chromosomal location

01

ABO

ABO

ABO

9q34.2

02

MNS

MNS

GYPA, GYPB, GYPE

4q31.21

03

P

P1

 

22q11.2–qter

04

Rh

RH

RHD, RHCE

1p36.11

05

Lutheran

LU

LU

19q13.32

06

Kell

KEL

KEL

7q34

07

Lewis

LE

FUT3

19p13.3

08

Duffy

FY

DARC

1q23.2

09

Kidd

JK

SLC14A1

18q12.3

10

Diego

DI

SLC4A1

17q21.31

11

Yt

YT

ACHE

7q22.1

12

Xg

XG

XG, MIC2

Xp22.33

13

Scianna

SC

ERMAP

1p34.2

14

Dombrock

DO

ART4

12p12.3

No.

System name

System symbol

Gene name(s)*

Chromosomal location

15

Colton

CO

AQP1

7p14.3

16

Landsteiner-Wiener

LW

ICAM4

19p13.2

17

Chido/Rodgers

CH/RG

C4A, C4B

6p21.3

18

H

H

FUT1

19q13.33

19

Kx

XK

XK

Xp21.1

20

Gerbich

GE

GYPC

2q14.3

21

Cromer

CROM

CD55

1q32.2

22

Knops

KN

CR1

1q32.2

23

Indian

IN

CD44

11p13

24

Ok

OK

BSG

19p13.3

25

Raph

RAPH

CD151

11p15.5

26

John Milton Hagen

JMH

SEMA7A

15q24.1

27

I

I

GCNT2

6p24.2

28

Globoside

GLOB

B3GALT3

3q26.1

29

Gill

GIL

AQP3

9p13.3

Note: Most of these groups (except ABO groups & Rh factor) are not taken into consideration in blood transfusion because their respective antibodies are normally not present in human plasma.

ABO grouping Blood type

Antigen on RBCs ))glycoproteins

Antibodies in plasma

Compatible donors

A B AB O

A

Anti-B )b(

A&O

B

Anti-A )a(

B&O

AB

None

A & B & AB & O

None

Anti-A )a( & Anti-B )b(

O

A ABC type Plasma antibod y

B

AB

O

(Universal recipient)

(Universal donor)

Notes: * ABO were discovered in 1900 and 1901 at the University of Vienna by Karl Landsteiner in the process of trying to learn why blood transfusions sometimes cause death and at other times save a patient.  In 1930, he received the Nobel Prize for this discovery. * When antigen-antibody reaction occurs, RBCs clump or agglutinate, and that is why the antigen and antibody are called agglutinogens and agglutinins. * For safe blood transfusion, the recipient must not have an antibody that would combine with the donor’s antigen which cause blood cell agglutination. * Java monkeys have 4 blood groups. * Chimpanzees lack blood group B. * Gorillas, gibbons, orangutans, … etc., do not have group O.

Rh factor * Persons with Rh antigen on the RBCs called Rh+ (Rh-positive) and those without it are Rh- (Rh-negative). * Rh- do not normally make antibodies to Rh antigen, but they make them when exposed to the Rh factor. * The Rh factor is important during pregnancy. Note: Rh+ is dominant on Rh-.

Father

Mother

Child

Rh+

Rh+

Rh+

√√

Rh-

Rh+

Rh+

√√

Rh-

Rh-

Rh-

√√

Rh+

Rh-

Rh+

XX

* Rh+ RBCs begin leaking across into the mother’s circulation as placental tissues normally break down before and at birth. This causes the mother to produce Rh antibodies.

* If the mother becomes pregnant with Rh+ baby, Rh antibodies may cross the placenta and cause destruction of the child’s RBCs. This is called fetal erythroblastosis. * This problem is solved by giving Rh- women a Rh-immune globulin injection just after the birth of an Rh+ child. * This injection contains Rh antibodies that attach the baby’s RBCs before these cells before these cells stimulate the mother’s immune system to produce its own antibodies just after the birth of an Rh+ child.

‫الى‬ ‫اللقــــــــــــــــــ‬ ‫ـاء‬ ‫أ‪ .‬د‪ .‬شــــــبل‬ ‫شـــــــــعلن‬