Friday, October 8, 2010

week 8


Circulatory System
            Internal environment provides the fluid environment needed
                        ECF or interstitial fluid
            Main function is to transport blood & lymph
                        Blood carries nutrients oxygen enzymes hormones among other things
            Closed system
                        Whole blood contained entirely within heart & vessels
                        Lymph picks up unneeded fluid & returns it to the lymphatic system for                                      cleaning and filtering which is also a part of bodily defense

            FUNCTIONS
                        Maintains homestasis
                        Transportation of oxygen, water, hormones, enzymes & antibodies
                        Regulation
                        Coordination
                        Water & other substance regulation
                        Temperature control
                        Phagocytosis à white blood cells

2 parts to the circulatory system
            Cardiovascular
            Lymphatic

Cardiovascular System

            Adequate blood needed for all body systems/organs at different times for different                     reasons making the circulatory very complex since it can redirect blood                               flow to parts of the body that need or don’t need it very quickly

            Ateries
            Arterioles
                        Both carry blood away from the heart and have higher pressure
            Veins
            Venules
                        Both carry blood to the heart and have a lower pressure
            Capillaries
                        What the circulatory system is designed around
                        Is the exchange zone for bloods nutrients and the organs used nutrients
                                    Blood moves slowly through capillaries to allow time for nutrients                                                           and waste to move into and out of the blood for use or                                                  transport

Internal inviroment
                        Blood
                                    Fluid & formed elements that are confined to organs of                                                              cardiovascular system
                        Tissue Fluid
                                    Interstitial fluid or ECF
                        Lymph
                                    Fluid in vessels of lymphatic system

Blood in detail

            Should have a pH value of 7.35 ~ 7.45
                        Making it a slightly basic fluid under normal conditions
            ~ 8% of body weight
            4 is normal Relative viscosity
                        depends on hematocrit temperature & flow rate
            4 ~ 6 Liters of blood on average in an adult

Plasma in detail
            90% water
            7 ~ 9% proteins
                        fibrin is a protein that helps blood clot
                                    made from fibrinogen
                        serum is plasma with Fibrin removed à all proteins except those used in                                               blood clotting
                                    55% of  all proteins are Serum Albumen (egg white) which is what                                             makes blood viscous & regulates blood volume
                                    38% are immunoglobulens à the bodies defense         
            1% salt sugars fats urea & other thing
            accounts for 50 ~ 60% of blood volume
            other 40 ~ 50% are formed elements
                        formed elements of the blood are erythrocytes (red blood cells),                                                leukocytes (white blood cells), and thrombocytes (platelets)
           
Eurythrocytes
            Red blood cell simply
            Mature cells lack a nucleus
            Hemoglobin gives the red color
                        Oxygen binds to Iron in the blood to be carried
            4 ~ 6 million/mm^3

Hematopoiesis
            The production of red blood cells
            Occurs in red bone marrow
            2 million/second produced to keep up with the bodies demand

Stem cell: One of the human body's master cells, with the ability to grow into any one of             the body's more than 200 cell types.

Reticulocyte
            Immature red blood cell
            Leaves bone marrow & enters blood stream & losses its nucleus

Luekocyte
            True cell
            6,000 ~ 10,000 /mm^3 of blood
            2 groups
                        Granular à granulocyte à white blood cell
                                    Has staining granules
                                    Polymorphonuclear
                                    Nuetrophil
                                    Eosinophil
                                    Basophil
                        Agranular
                                    Monocyte
                                                Can develop in macrophages
                                    Lymphocyte
                                                B cells
                                                T cells
                                                NK cells

Thrombocytes
            Platelets
            250,000 / mm^3 of blood
            fragments of megakaryocyte cell
            rounded
            colorless
            sticky à to adhere to cuts or breaks in a vessel

Hemostasis
            Stopping of blood flow
            Smooth muscle spasms to constrict blood flow
            Platelet plug should form at the site of the damage to start to the repairing process

THE HEART
            2 purposes
                        Completes the Pulmonary circuit for oxygenation of blood
                        Completes the systemic circuit for getting the rest of the body the it needs
            Double Pump
            Maintains flow & pressure
            70 ~ 75 beats/contractions a minute in the average human
            highly efficient to maintain its output
            weigh 340 grams ~ 11 ounces
            12cm long à 9cm wide à 6cm thick
                        less than 648 cm^3 because its not a perfect cube
                        Roughly the size of ones clinched fist
            Located in the mediastynum
            2/3 of it lies to the left of the bodies midline
            1/3 of it lies to the right of the bodies midline
            Posterior to the sternum
            Anterior to the vertebrae & descending aorta & esophagus
            Parietal pericardium adheres to the diaphragm
            Medial to the lungs

            Endocardium
                        Fibrous tissue that supports the endothelium
                        Inner most layer that lines the heart
            Myocardium
                        CT & cardiac muscles
                        Supports lymph
                        Thinner in the walls of the Atrias
                        Right Ventricle 1/3 inch thick
                        Left Ventricle 1 inch thick
                        Arrangement of whirls helps to empty blood
                        Not smooth
                                    Trabeculae carneae
                                                are rounded or irregular muscular columns which project                                                           from the whole of the inner surface of the ventricle

            Capillary bed
                        A dense network of tiny blood vessels that enables blood to fill a tissue or                                  organ

            Epicardium
                        Visceral layer of pericardium
                        the outermost of the three layers of tissue that form the heart wall
                        The inner layer of the pericardium that is in contact with the surface of the                                  heart
           
            Parietal cardium
                        Outer layer of pericardium
                        forms the sac and is lined with a serous membrane. Also called heart sac

            Pericardial cavity
                        Lies between the epicardium and parietal cardium
                        Serous or watery membrane
                        Serous fluid is used as lubrication for the heart
                                    Provides almost 0 friction

            4 chambers to the Heart
                        2 atrium both are superior used to receive blood
                        2 ventricles both are inferior use to pump blood away

            the hearts veins & artery locations
                        Coronary sulcus
                                    Lies between the atrium & ventricle
                        Anterior interventricular sulcus
                                    Between the ventricles
                        Posterior interventricularu sulcus
                                    Between the ventricles

            RIGHT ATRIUM
                        Gets blood returning from systemic route
                        3 openings
                                    Superior vena cava
                                                Superior & posterior
                                                Returns blood from shoulders and up
                                                Directed downward
                                                No valve
                                    Inferior vena cava
                                                Posterior & inferior
                                                Directed upward
                                                Brings in blood from the trunk down
                                                Has foramen ovale
                                                            Fossa ovalus forms after birth
                                                Eustachion valve
                                                            Only seems to be active while a fetus
                                                            No known function for adults
                                    Coronary Sinus
                                                Large veinous
                                                Brings blood back to the heart from the heart
                                                Thebesian valve
           
            RIGHT VENTRICLE
                        Opening between the right atrium & right ventricle
                        Controlled by Tricuspid valve
                                    Tough fibrous tissue
                                    Opens during diastole (relaxation)
                                    Closes duing systole (contraction)
                                    Preventing backflow
                                                Has 3 chordae tendoneae
                                                Attached to 3 papillary muscles
                        Opens to pulmonary trunk
                                    Flow controlled by pulmonary semilunar valve

            LEFT ATRIUM
                        Small in size
                        Walls are thicker than right atrium
                        4 pulmonary veins
                        No valves

            LEFT VENTRICLE
                        Same size as right ventricle
                        Walls are 3x thicker than the right side
                                    To accommodate the higher pressure needed
                        Opening between left ventricle & atrium
                        Controlled by Bicuspid valve (mitral)
                                    2 flaps
                                    2 tendons
                                    2 papillary muscles
                                    All stronger and thicker than the right ventricle
                        Pumps into the aorta
                        Controlled by Aortic Semilunar Valve
                                    Opens with systole
                        Aortic sinuses
                                    For coronary arteries
                                    Receives blood in Diastole


No comments:

Post a Comment