Cardiovascular and Respiratory System Flashcards
What are the boundaries of the thoracic cavity
Cranially: Thoracic inlet
Caudally: Diaphragm
Ventrally: Sternum
Dorsally: Vertebrae
Laterally: Ribs
What is pleura?
Serous membrane
What innervates the diaphragm?
Phrenic nerve
What is the diaphragm made of?
Tendinous centre
Muscular periphery
What are the three holes in the diaphragm?
Aortic hiatus (Aorta)
Caval foramen (Vena cava)
Oesophageal hiatus (Oesophagus)
Which lung is bigger and why?
Right lung because the heart lies slightly to the left of the midline
What is the name of the valves separating the atria from the ventricles?
Atrioventricular valves
How many cusps does the right atrioventricular valve have?
3 (tricuspid)
How many cusps does the left atrioventricular valve have?
2 (bicuspid)
What hold the valves so that they don’t invert?
Chordae tendinae connected to the papillary muscles
What is the pericardium?
A sac surrounding the heart
What are the two types of cardiac cell?
Contractile
Non-contractile (autorhythmic cells)
What are intercalated discs?
Specialised connections between cells which allow excellent impulse transmission
Where is the neural input to the heart from?
Medulla oblongata
Why does the blood pressure decrease as the blood moves away from the heart?
Blood vessels divide
Friction causes loss of energy
What is the sinoatrial (SA) node?
Natural pacemaker
What is the Bachman’s bundle?
It sends the impulses to the left atria so that both atria contract at the same time
What is the hierarchy of conduction in the heart?
SA node
Bachman’s bundle
Atrioventricular (AV) node
Bundle of His
Right and left bundle branches
Purkinje fibres
What is the cardiac output equation?
Cardiac output (CO) = Heart rate (HR) x Stroke volume (SV)
What are the differences between arteries and veins?
Arteries: Carries blood away from the heart
Oxygenated blood (except the pulmonary artery and the umbilical arteries)
Small, round lumen
Thick, muscular and elastic walls
No valves
Veins: Carries blood towards from the heart
Deoxygenated blood (except the pulmonary vein and the umbilical vein)
Large, irregular lumen
Thin walls
Valves
What are the three types of capillary?
Continuous
Fenestrated
Discontinuous/Sinusoidal
What is the upper respiratory tract?
Everything above the trachea:
Nares > Nasal passages > Pharynx > Larynx
What is the lower respiratory tract?
Trachea and below:
Trachea > Bronchi > Bronchioles > Alveoli
What is the ventilation zone?
Movement of air
No gas exchange
Air humidified, warmed and cleared of debris
Nares to bronchioles
What are the functions of the nasal cavities?
Conduction of air (moistens and warms air and filters particles)
Olfaction
What borders the nasal cavity?
Dorsally and laterally: Facial bones
Ventrally: Hard palate and oral cavity
Rostrally: Nares
Caudally: Pharynx
What is an obligate nasal breather?
An animal which is unable to breathe effectively through their mouths (e.g. horses)
What are the three pharynx cavities?
Oropharynx
Nasopharynx
Laryngopharynx
What is the larynx?
Connects the pharynx to the trachea
Protects the LRT from food and water
Produces sound (voice box)
What is the differences between the trachea and bronchi, and the bronchioles?
Trachea and bronchi:
Hyaline cartilage
Goblet cells, submucosal glands
Ciliated epithelium
Bronchioles:
No cartilage
No submucosal glands
