Lab 7 Flashcards
What can be said about the similarity of the pulmonary and systemic circulations of turtles, snakes and lizards?
have partially separated pulmonary and systemic circulations
Oxygenated blood is received where in turtles, snakes, lizards?
left atrium receives oxygenated blood from pulmonary veins
Deoxygenated blood is received where in turtles, snakes and lizards?
right atrium receives deoxygenated blood from the sinus venosus
In turtles, snakes and lizards, what happens when the atria contracts?
when the atria contracts, the atrioventricular valves cover the opening of the intraventricular canal, temporarily separating the ventricle into two parts, confining the oxygenated blood in the cavum arteriosum and the deoxygenated blood in the cavum pulmonale
In turtle, snakes and lizards, what happens when the ventricle contracts?
- when the ventricle contracts, the muscular ridge makes contact with the ventricle wall creating a separation between the cavum venosum and cavum pulmonale, preventing a back flow of blood
- the atrioventricular valves close, opening the intraventricular canal, permitting the oxygenated blood in the cavum arteriosum to flow into the cavum venosum and out the aorta, while deoxygenated blood flows from the cavum pulmonale into the pulmonary arteries
When would mixing of oxygenated and deoxygenated blood flowing into the systemic circulation occur in turtle, snakes and lizards?
under physiological stresses like diving
What can be said about the crocodilian and birds’ hearts?
- a complete septum in the ventricle
- four chambered heart
The right atrium of crocodilians and birds receives blood from?
right atrium receives blood from the head and body via the caval veins
The left atrium of crocodilians and birds receives blood from?
left atrium receives oxygenated blood from the lungs via the pulmonary veins
How is blood pumped into the aorta of crocodilians and birds?
left ventricle pumps blood into the aorta
What is the difference between the systemic arches of crocodilians and birds?
crocodilians have left and right systemic arches
birds have only a single right systemic arch
Venous blood is pumped from the right atrium to then go to which other places in the circulation system of reptilians?
venous blood flow from the right atrium, is pumped into the right ventricle, contraction of the right ventricle pumps deoxygenated blood into the pulmonary trunk which branches to the right and left of the lungs as pulmonary arteries
How is ventilation accomplished in reptilians? How does the system work? What is an additional structure that helps accomplish this process in crocodilians?
- lack a diaphragm
- action of aspiration pump
- actions of muscles/ribs enlarges the body cavity around the lung to draw air in and contracted to expel air
- aided by the liver in crocodilians
What allows for ventilation in turtles?
movement of the head and limbs into and out of the shell changes the pressure in the cavity and contributes to inhalation and exhalation
Contraction and relaxation of which muscles in the turtle alters the volume of the visceral cavity and cause inhalation and exhalation?
rectus abdominus and external abdominal obliques
What are the roles of longissimus dorsi and longus colli in the turtle?
extend the neck and head
Where does the longus colli originate and insert in the turtle?
originates and inserts on the cervical vertebrae
Where is the longissimus dorsi located on the turtle and where does it insert?
runs along the vertebral column and inserts on posterior cervical vertebrae
Where does the spinal cervical originate and insert in the turtle? What is its function?
- originates on middle cervical vertebrae and inserts on last cervical vertebrae
- raises and extends the neck
What can be said about the ventricle of the turtle?
has a partially separated ventricle
What can be said about the atrium of the turtle?
the heart is composed of fully separated left and right atria
Describe the various components of blood circulation in the turtle.
- sinus venosus receives deox blood from precaval and postcaval veins and then empties into right atrium
- right aortic arch gives rise to brachiocephalic trunk, which then separates into two subclavian arteries
- brachiocephalic trunk also gives rise to pair of common carotid arteries from its dorsal surface
- ventral cervical artery arises from subclavian artery
- axillary artery gives rise to vessels to plastro, pectoral girdle and forelimb
- left and right aortic arches give rise to the dorsal aorta, which gives rise to the arteries to the digestive tract
- pulmonary trunk becomes right and left pulmonary arteries
- right pulmonary artery passes into lung
Which three large vessels emerge from the ventricle of the turtle?
right aortic arch, left aortic arch and pulmonary trunk
Which vessel that emerges from the ventricle carries the most highly oxygenated blood in the turtle?
all the blood to the head and forelimbs originates from the right aortic arch and therefore carries the most highly oxygenated blood
Which vessel that emerges from the ventricle receives primarily deoxygenated blood?
pulmonary trunk
Function of the stomach?
secretes acids and enzymes to digest food
Function of the liver?
detoxification, secretes bile
Function of pancreas?
secretes enzymes and digestive juices into the intestine for further digestion
Function of gall bladder?
storage of bile
Function of caecum?
absorbs fluids and salts after digestion
Function of spleen?
filter for blood, recycling red blood cells
What would be the consequence of a blockage in the cystic duct?
gall bladder would become inflamed due to bile accumulating but not being able to exit this place of storage