A and P 2 Unit Exam 1

The 3 main components of Cardiovascular system

1. Heart

2. Blood Vessels

3. Blood

Blood

- Connective tissue transported by cardiovascular system

- Different from other connective tissue because its matrix/ground substance is

- fluid

- Lacking fibers

- not produced by the tissue's cells.

- Average adult has 4-6 liters

Hematology

The study of blood

Blood plasma

- Fluid ground substance in blood

- Produced from tissue fluid (directly outside of body cells)

Blood composition

- Formed elements 45%

- Plasma 55%

Formed Elements

Red blood cells(erythrocytes)

White blood cells(leukocytes)

Platelets(thrombocytes)

Hematopoiesis

- The production of blood cells

- In red bone marrow from hematopoietic stem cells called hemocytoblasts

Types of hematopoiesis

Erythropoiesis

Leukopoiesis

Thrombopoiesis

Centrifuging

Testing commonly used to separate components of a blood sample

Plasma composition

- Mostly water 92%

- Proteins (plasma proteins) 7%

- Other solutes 1%

Plasma proteins

- Albumins

- Globulins

- Fibrinogen

Albumin

(Most abundant)

- Help maintain osmotic pressure

- Maintain solute concentration of blood and therefore control whether blood is gonna have water move in or out of it by osmosis

Globulins

- Antibodies: plasma proteins that help protect from infection, stick to pathogens and mark them for destruction by wbcs

- Some Transport substances in the body like lipids

Fibrinogen

(Least abundant)

- Protein that can be converted into insoluble fibers that get tangled together at a wound which serves as a scaffolding where a blood clot forms(Coagulation)

Solutes in plasma proteins

Electrolytes: sodium, potassium, calcium

Organic nutrients: glucose, monosaccharides, amino acids

Organic wastes: organic molecules produced from metabolic reactions; kidneys will filter out

Coagulation

Blood clot formation

Red blood cells

Erythrocytes

- ⅓ hemoglobin by volume

- Biconcave disk shape

- No nucleus at maturity (amitotic)

- 5.2 million/mm3

Hemoglobin

- Protein contained in cytoplasm of rbcs

- The protein that binds to oxygen gas and transports it inside the rbc

Biconcave shape

- High surface area to volume ratio

- All cytoplasm is near the plasma membrane

- Smooth and flexible

- Able to form stacks that slide through small capillaries

Anemia

Any condition in which the ability of the blood to transport oxygen gas is diminished

Anemia chart

Reticulocyte

Cells that become red blood cells

Sickle cell anemia

Hemoglobin is abnormal, which causes the red blood cells to become hard and sticky and look C-shaped

Oxyhemoglobin

- When hemoglobin binds to oxygen gas

- Bright red

- Happens with cuts because blood is exposed to air

Deoxyhemoglobin

When hemoglobin released and is not carrying oxygen gas

Darker red

Carbon monoxide

- Produced when you burn organic fuel

- Sticks to hemoglobin better than oxygen

Structure of hemoglobin

- Quaternary structure

- 4 polypeptides (chains of amino acids)

- 2 alpha chains

- 2 beta chains

Heme group(Blue) & Iron atom(red)

- The spot where oxygen gas binds, binds to iron atoms in heme groups

- Found in the center of each of the 4 polypeptides

Red blood cell life cycle

- Production of rbc is influenced by blood's ability to transport oxygen gas

- If blood oxygen gas level gets low it stimulates liver to secrete erythropoietin

- RBCs lifespan is about 120 days

- Spleen/liver get rid of damaged rbcs

erythropoietin

Hormone that stimulates red blood cell production

Macrophages (WBC)

- (big eater)

- Engulf rbcs when they are removed from circulation by spleen/liver

- Highly phagocytic

- Engulf and debris/remnants of broken cells and digest in cytoplasm

Bilirubin/Biliverdin

- What's left of the heme group when separated from iron

- A pigment molecule, orange

- Excreted from liver into small intestine

- Released from body in feces

Too much bilirubin

Causes jaundice (yellow eyes or skin)

Fate of hemoglobin following RBC destruction and phagocytosis by a macrophage

- Polypeptides are hydrolyzed and amino acids are recycled or metabolized

- Iron is removed from each heme and transported to red bone marrow to be recycled

- The remainder of each heme becomes biliverdin (green) or bilirubin (orange) which are transported to the liver for excretion

Phagocytosis

The process of removing debris and pathogens by engulfing and digesting them

RBC Surface Antigens

Genetically determined cell surface recognition molecules that can cause an immune response in individuals lacking those antigens

Antibodies

Plasma proteins (immunoglobins) from B-cells that bind to foreign antigens

Agglutination

Rbc clump together because antibodies bind to their antigens

ABO blood typing

Tests for:

- Antigens A and B

- Antibodies anti-A and anti-B

Rh blood typing

Tests for:

- Antigen D

- Antibody anti-D

What happens to antibodies bind to antigens

- Causes agglutination

- The blood cells that bare those antigens to clump

- Insoluble clump of antibodies bound to antigens on RBC surfaces

- Involves rbcs because antibodies have bond to their antigens

Antigen/Antibodies chart

Blood transfusion chart

Why can't a person receive certain cells?

A person cannot receive cells that have antigens to which his/her antibodies can bind.

What happens if antibodies and antigen bind

It can cause clumping and hemolysis

Hemolysis

Breaking of blood cells

Rh blood system chart

Rh+ can receive + or -

Rh- can only receive -

Rh sensitization

White Blood Cells

Leukocytes

- Have a nucleus at maturity(nucleate)

- protect the body against infection

- Live for many years

- Function primarily outside of the cardiovascular system

- 7000/mm3

2 Categories of white blood cells

1. Granulocyte

2. Agranulocytes

What are Granulocytes

Cells that in cytoplasm have tiny granules, so cytoplasm looks grainy

Granulocyte white blood cells

- Neutrophils

- Eosinophils

- Basophils

What are Agranulocytes

cells that don't have granules

Agranulocyte white blood cells

- Monocytes

- Lymphocytes

Margination

White blood cell is stuck to the lining of the wall of a capillary/blood vessel wall

Emigration/Diapedesis

White blood cell crosses wall of capillary through the cells of wall(simple squamous)

Positive Chemotaxis

Movement in particular direction because of chemical, towards the chemical

5 types of White Blood Cells

Neutrophils

Lymphocyte

Monocyte

Eosinophil

Basophil

Neutrophil

- Most abundant type of white blood cells

- Round, nucleus has lobes(multilobe), cytoplasm has large pale inclusions

- Phagocytic- engulf pathogens or debris in injured/infected tissues

- Can release enzymes/chemicals that are toxic to infecting cells like bacteria

- Bigger than red blood cell

Eosinophil

- 4th most abundant white blood cell

- round, nucleus has 2 lobes, large granules, bright red

- Phagocytic- engulf antibody labeled materials

- Increase in abundance during allergic reaction

Basophil

- Rarest of white blood cells

- Round cell, nucleus can't be seen, dark purple staining

- Enter damaged tissues and release a chemical histamine

Lymphocyte

- 2nd in abundance

- Smallest, not much bigger than rbc

- Nucleus takes up almost whole interior, very little cytoplasm

- Cells of lymphatic system

- Provide immunity (protection against specific diseases)

- T cells and B cells

Monocytes

- 3rd in abundance

- Biggest white blood cell, 4-5x size of rbc, large cell, nulcuea shaped like kidney

- Enter tissue and become macrophages

- When monocytes are stimulated, they change into macrophages

Histamine

Chemical that promotes inflammation

Platelets

Thrombocytes

- Cell fragments of megakaryocytes

- Live 10 days on average

- 350,000/mm3

Platelets blood prevention

- By releasing chemicals that promote coagulation and vasoconstriction

- Can stimulate blood vessel to constrict so less blood goes through it

- Become sticky and will stick to collagen fibers in blood vessel wall and form a platelet plug

Vasoconstriction

the narrowing of blood vessels

Megakaryocyte

(cell with the big nucleus)

- Cell breaks up into platelets

Blood Cell Chart

Hemostasis

- The prevention of blood loss

- Maintaining a constant internal blood supply

- Uses hemostatic mechanisms to prevent blood loss

Hemostatic mechanisms

- Vascular phase

- Platelet phase

- Coagulation phase

Vascular phase

- If blood vessel is cut, stimulates vascular spasm, in blood vessel wall smooth muscle tissue will contract constricting blood vessels so lumen gets smaller/tighter so blood can't escape

- Following injury to a blood vessel, endothelial cells lining the blood vessel wall release chemicals that stimulate smooth muscle contraction.

- The endothelial cells also become sticky

- Cut ends of vessels can stick back together

- Opposite sides of capillary wall can stick together

Platelet phase

- Formation of a temporary platelet plug

- Platelets get sticky and stick to blood vessel walls, especially collagen fibers, and to each other and form platelet plug until clot forms

Coagulation phase

2 pathways for starting coagulation

Intrinsic

Extrinsic

Intrinsic pathway (right side of diagram)

Caused by blood contact with damaged or foreign surface (e.g. coagulation within a test tube)

- Starts with chemical that are normal components of the blood

- Chemicals that are part of blood come into contact in the body with an irregular surface

- Or outside of the body if the chemicals come into contact with a foreign surface

- Often occurs when blood comes into contact with a lining of blood vessel thast been damaged or has accumulation of plaque

Extrinsic pathway (left side)

Caused by chemicals released by broken blood vessels or damaged tissues

- Promoted by chemicals that are not part of the blood, that are released from damaged tissues

- Chemicals from another source

Common pathway for coagulation phase

- Both chemicals stimulate a chemical called factor x

- Activates molecule called prothrombin activator

- Changes a chemical prothrombin into thrombin, which

- changes plasma protein called fibrinogen into fibrin

- Fibrinogen is plasma protein that dissolves in blood plasma that when with thrombin it will precipitate forming solid protein threads in blood called fibrin, which gets tangled at wound site and form the netting that traps blood cells and forms clot

Heart Structure

- Fist-sized organ in the mediastinum of the thoracic cavity

- Wall has three layers

Endocardium

Myocardium

Epicardium

- Surrounded by a pericardial sac

Endocardium

Inner layer

- Consists of 2 tissue

1. Endothelium:

- Tissue that comes into contact with blood inside heart chamber, sits on top of areolar

- Simple squamous epithelium=endothelium

2. Areolar tissue: Yellow section of endocardium

- Connective tissue(glue) bind other tissues together

Myocardium

Middle layer

- Thick layer of cardiac muscle tissue

- Can contract in order to pump blood

Epicardium

Outer layer (Visceral Pericardium)

- 2 tissues

1. Areolar tissue

2. Simple squamous epithelium/Mesothelium: thin layer

Pericardial sac

Containing a serous fluid-filled pericardial cavity

- Visceral pericardium = epicardium

- Parietal pericardium

- Serous layer

- Fibrous layer

Base of heart

- Top of heart

- Blood vessels attached to it

Apex of heart

Bottom of heart

Sulcus

Shallow groove between heart structures

Coronary sulcus

- Sulcus dividing atria and ventricles

- Filled with fat and blood vessels

Anterior/posterior interventricular sulcus

Sulcus that divides the two ventricles

Septum

Wall between heart chambers

Interventricular septum

Wall between two ventricles

Interatrial septum

Wall between atria

Auracle

Ear-like flaps externally at the edge of the atria

Pectinate muscle

Muscle tissue that consists of interconnecting bands/ lining of atria

trabeculae carneae

Branchy muscle that lines ventricles

Papillary muscles

The muscle chordae tendineae connect too

Chordae tendineae

(heart strings) the string like fibrous connections between valves and papillary muscles

Blood Vessels of the heart

Aorta

Vena Cava

Pulmonary artery

Pulmonary veins

Heart Chambers

- Atria

- Ventricles

Right atrium (with auricle)

- Receives deoxygenated blood from the superior and inferior venae cavae

- Pumps blood to the right ventricle

Left atrium (with auricle)

- Receives oxygenated blood from the pulmonary veins

- Pumps blood to the left ventricle

Right ventricle

- Receives blood from the right atrium

- Pumps blood to the pulmonary trunk and pulmonary arteries