Cardiovascular System Flashcards
Comment on the shape of the heat at birth
It is transverse and appears large in proportion to the diameter of the chest cavity
Between what age does the heart acquire its adult shape and weight
Puberty to 25 years old
In adults the shape of the heart tends to resemble that of
The chest
The heart is approximately the size of
Your fist
What is the size of the average human heart?
14 cm by 9 cm
Where does the heart lie?
In the mediastinum under the sternum
Where does its apex extend to?
The fifth intercostal space
Location anteriorly and posteriorly
Anterior to vertebral column and posterior to the sternum
Which points of attachment of the ribs is the heart located?
Attachment 2 to 6
Hearts mass
2/3 is on the Left of the midline and 1/3 is to the right of the midline
Where is the mediastinum located?
Medial portion of the thoracic cavity between the lungs
The mediastinum contains
Trachea, esophagus, thymus gland and the heart and greater blood vessels
The outer covering of the wall is the
Pericardium
What are the two layers of the pericardium
Fibrous - tough loose fitting sac and serous- parietal layer lies in inside the fibrous pericardium, visceral layer covers the outside of the heart
What is the pericardial space?
Lies between parietal and visceral layers and contains 10-15 ml of pericardial fluid
Functions of heart coverings
Anchors the heart, prevent overfilling and protection against friction
Epicardium is
A visceral layer of serous pericardium taht contains connective tissue and epithelium along with lymph capillaries, blood and coronary arteries
Myocardium
Cardiac muscle tissue forming the bulk of the heart
What is the fibrous skeleton of the heart?
It is interconnected, criss crossing, intertwining layer of connective tissue.
Endocardium is
Inner myocardial surface and is made up
Of connective tissue and epithelium and is continuous with the epithelium of the major vessels of the heart
Which layer contains the purkjnie fibers?
Endocardium
Vessels that return blood to the heart are:
Right and left pulmonary veins and inferior and superior vena cava
Vessels that carry blood away from the heart
Aorta
Fight and left pulmonary arteries
What chambers are the receiving chambers of the heart?
Atria
What does each atria have
Auricle and pectinate muscles
Where does blood come from to the atria?
Right from vena Cavae
Left from pulmonary vein
What are ventricles?
Discharging chambers of the heart
Muscles that mark the ventricles
Trabeculae carneae and papillary muscles
How does the ventricles give blood ?
Right ventricle gives the pulmonary trunk and left ventricle gives aorta
What causes the thickness of the chamber
The function
Compare thickness of atria and ventricles
Atria - thin
Ventricles are much thicker especially the left ventricle
Skeleton of the heart
Connected rings serves as semi rigid support of heart valves and attachment of cardiac muscles of myocardium
Where is the electrical barrier of the myocardium?
Atria and ventricles
What is the role of heart valves?
Ensures unidirectional blood flow
Where is the SV valve ?
Between Atria and ventricles
What joins the AV valve to the papillary muscles
Chordate tendineae
What valves prevent flow back into the ventricles
Semilunar
Where do these semilunar valves lie?
Aortic semilunar lies between the left ventricle and the aorta
Pulmonary semilunar valve is located between right ventricle and the pulmonary trunk
What produces heart sounds ?
Vibrations in heart tissues as blood rapidly changes velocity.
What is the sound ?
Lubb - dupp
What causes the first sound lubb?
Closing of AV valve
Ventricular systole
Contraction
The second sound dupp is caused by the
Closeting of aortic and pulmonary semilunar valves (diastole)
What is coronary circulation?
Functional blood supply to the heart muscle itself.
What does the inners mucosal cells release
Glycogen
What neutralizes vaginal acidity?
Semen
What is the uterus shaped like?
Pear
Parts of the uterus
Body and cervix
Circular recesss
Vaginal fornix
Cervical canal that has a small opening called
Cervical is
What is the bulging part of the uterus
Fundus
How does the cervix point
Backwards and downwards joining at right angle
Several ligaments such as
Posterior
Anterior
Two broad
Two round
Two uterosacral
Three layers of the uterus 🕋🙃
Endometrium, myometrium and perimetrium
Layer composed of compact spongy and basal layer
Endometrium
What is the placenta?
Permits the exchange of materials between mother and child
Where does the uterus lie
In upper free margins of broad ligaments
Three divisions of uterine
Isthmus, ampulla and infundibulum
Gametes
Oocytes and ovum
Parts of ovary
Medulla consists of supporting connective tissue, blood vessel and nerve
The cortex contains follicles at various stages
Have a oocyte and supporting follicular cells
Mammary lobes is separated by
Septa
Help support the breast
Suspensory ligaments
Nipples are surrounded by
Areola
What stimulates lactation?
Prolactin
Ejection of milk
Oxytocin
Primary sex organs
Gonads
What is the urethra?
Terminal male duct which carries urine or semen to the outside
Collateral routes?
Ensure that blood is delivered even if major vessels are occluded
Blood enters coronary sinus to enter
Right atrium
Autorthymic cells use
Calcium influx instead of sodium
Cardiac muscles
They are striated, short, fat, branched and interconnected
What anchors cardiac cells together
Intercalated dics and allows for free passage of ions
What is the refractory period
250 ms
What is the normal resting heart rate?
Less than 100 beats per minute normally 75
Which node sets the pace of the heart beat?
SA
AV node delays message by
0.1 second
Conduction system of the heart component?
SA, AV nodes , AV bundle and sub endocardium Branches
