Overview of the cardiovascular & respiratory tract Flashcards
summary of the Functions of the cardiovascular system
Transport of oxygen and nutrients to cells Removal of metabolites from cells Defence Carrying hormones Thermoregulation
Components of the cardiovascular system
Heart Blood vessels; arteries veins microcirculation
Blood pressure in pulmonary artery=
15-30mmHg
4-12mmHg
Aortic blood pressure =
100-140mmHg
60-90mmHg
Systole
contraction of the ventricles, ejecting the blood into the aorta and pulmonary artery
Diastole
relation of the heart muscle to allow filling
Valves of the heart
Atrioventricular valves
Semilunar valves
Cardiac skeleton
Dense connective tissue
Insulation between atria and ventricles
Conductivity
The conducting system of the heart consists of cardiac muscle cells and conducting fibers (not nervous tissue) that are specialized for initiating impulses and conducting them rapidly through the heart. They initiate the normal cardiac cycle and coordinate the contractions of cardiac chambers. Both atria contract together, as do the ventricles, but atrial contraction occurs first.
cardiac cycle
atrial systole> isovolumic ventricular contraction> ventricular systole> ventricular distole
the apex of the heart shows…
the left ventrical
Cardiac Output
Cardiac output is the amount of blood pumped out of the heart per minute
Cardiac output= stroke volume x heart rate
Stroke volume = amount of blood pumped out of the left ventricle in 1 contraction
Heart rate, bpm, varies between species
Heart rate mouse
310-840
hart rate rabbit
140-180
heat rate cat
120-140
heart rate dog
70-120
heart rate sheep
65-80
heart rate cow
50-80
heart rate horse
30-42
Preload
the amount of stretch of the sarcomeres in the cardiac myocytes at the end of ventricular filling
Afterload
the pressure the heart works against to eject blood during ventricular contraction
Ejection Fraction
the percentage of blood pumped out of the ventricle by a contraction, expressed as a percentage
Functions of the respiratory system
Maintain levels of oxygen, carbon dioxide and hydrogen ions in the body
Ficks Law- diffusion takes place from an area of high concentration to an area of low concentration proportional to the concentration gradient
Upper respiratory tract
the sinuses, nasal passages, pharynx, and larynx. These structures direct the air we breathe from the outside to the trachea and eventually to the lungs for respiration to take place.
Lower respiratory tract
The major passages and structures of the lower respiratory tract include the windpipe (trachea) and within the lungs, the bronchi, bronchioles, and alveoli.
Pulmonary Circulation
Pulmonary circulation moves blood between the heart and the lungs. It transports deoxygenated blood to the lungs to absorb oxygen and release carbon dioxide. The oxygenated blood then flows back to the heart. Systemic circulation moves blood between the heart and the rest of the body. It sends oxygenated blood out to cells and returns deoxygenated blood to the heart.
The blood first enters the right atrium.
The blood then flows through the tricuspid valve into the right ventricle.
When the heart beats, the ventricle pushes blood through the pulmonic valve into the pulmonary artery.
The pulmonary artery carries blood to the lungs where it “picks up” oxygen and then leaves the lungs to return to the heart through the pulmonary vein.
The blood enters the left atrium, then descends through the mitral valve into the left ventricle.
The left ventricle then pumps blood through the aortic valve and into the aorta, the artery that feeds the rest of the body through a system of blood vessels.
Blood returns to the heart from the body via two large blood vessels called the superior vena cava and the inferior vena cava. This blood carries little oxygen, as it is returning from the body where oxygen was used.
The vena cavas pump blood into the right atrium and the cycle of oxygenation and transport begins all over again.
Systemic circulation
the circuit of vessels supplying oxygenated blood to and returning deoxygenated blood from the tissues of the body, as distinguished from the pulmonary circulation.
Lung capacity mouse: Respiratory rate (bpm)
and Tidal volume (ml)
109 bpm
0.18
ml
Lung capacity rat: Respiratory rate (bpm)
and Tidal volume (ml)
97bpm
1.55 ml
Lung capacity rabbit: Respiratory rate (bpm)
and Tidal volume (ml)
39bpm
15.8 ml
Lung capacity cat: Respiratory rate (bpm)
and Tidal volume (ml)
30bpm
34ml
Lung capacity dog: Respiratory rate (bpm)
and Tidal volume (ml)
21bpm
144ml
Lung capacity cow : Respiratory rate (bpm)
and Tidal volume (ml)
30bpm
3800ml
Lung capacity horse: Respiratory rate (bpm)
and Tidal volume (ml)
12bpm
6700ml
Pleural membranes
Visceral Parietal Costal Diaphragmatic mediastinal Thin layers that reduce friction between the lungs and the inside of the chest wall during breathing.
Mediastinum
•heart in pericardiac sac •Thoracic trachea •Thoracic oesophagus •Thymus •Mediastinal LN •Great vessels •Nerves a membranous partition between two body cavities or two parts of an organ, especially that between the lungs.
histology of cardiac muscle
Cardiac muscle is striated, like skeletal muscle, as the actin and myosin are arranged in sarcomeres, just as in skeletal muscle.
However, cardiac muscle is involuntary.
Cardiac muscle cells usually have a single (central) nucleus. The cells are often branched, and are tightly connected by specialised junctions. The region where the ends of the cells are connected to another cell is called an intercalated disc
The intercalated disc contains gap junctions, adhering junctions and desmosomes.
Gap junctions allow the muscle cells to be electrically coupled, so that they beat in synchrony
Coronary circulation- blood supply to the heart
Coronary circulation is the circulation of blood in the blood vessels that supply the heart muscle (myocardium). Coronary arteries supply oxygenated blood to the heart muscle, and cardiac veins drain away the blood once it has been deoxygenated
