Lab 7

Question 1

What can be said about the similarity of the pulmonary and systemic circulations of turtles, snakes and lizards?

Answer 1

have partially separated pulmonary and systemic circulations

Question 2

Oxygenated blood is received where in turtles, snakes, lizards?

Answer 2

left atrium receives oxygenated blood from pulmonary veins

Question 3

Deoxygenated blood is received where in turtles, snakes and lizards?

Answer 3

right atrium receives deoxygenated blood from the sinus venosus

Question 4

In turtles, snakes and lizards, what happens when the atria contracts?

Answer 4

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

Question 5

In turtle, snakes and lizards, what happens when the ventricle contracts?

Answer 5

• 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

Question 6

When would mixing of oxygenated and deoxygenated blood flowing into the systemic circulation occur in turtle, snakes and lizards?

Answer 6

under physiological stresses like diving

Question 7

What can be said about the crocodilian and birds’ hearts?

Answer 7

• a complete septum in the ventricle

- four chambered heart

Question 8

The right atrium of crocodilians and birds receives blood from?

Answer 8

right atrium receives blood from the head and body via the caval veins

Question 9

The left atrium of crocodilians and birds receives blood from?

Answer 9

left atrium receives oxygenated blood from the lungs via the pulmonary veins

Question 10

How is blood pumped into the aorta of crocodilians and birds?

Answer 10

left ventricle pumps blood into the aorta

Question 11

What is the difference between the systemic arches of crocodilians and birds?

Answer 11

crocodilians have left and right systemic arches

birds have only a single right systemic arch

Question 12

Venous blood is pumped from the right atrium to then go to which other places in the circulation system of reptilians?

Answer 12

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

Question 13

How is ventilation accomplished in reptilians? How does the system work? What is an additional structure that helps accomplish this process in crocodilians?

Answer 13

• 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

Question 14

What allows for ventilation in turtles?

Answer 14

movement of the head and limbs into and out of the shell changes the pressure in the cavity and contributes to inhalation and exhalation

Question 15

Contraction and relaxation of which muscles in the turtle alters the volume of the visceral cavity and cause inhalation and exhalation?

Answer 15

rectus abdominus and external abdominal obliques

Question 16

What are the roles of longissimus dorsi and longus colli in the turtle?

Answer 16

extend the neck and head

Question 17

Where does the longus colli originate and insert in the turtle?

Answer 17

originates and inserts on the cervical vertebrae

Question 18

Where is the longissimus dorsi located on the turtle and where does it insert?

Answer 18

runs along the vertebral column and inserts on posterior cervical vertebrae

Question 19

Where does the spinal cervical originate and insert in the turtle? What is its function?

Answer 19

• originates on middle cervical vertebrae and inserts on last cervical vertebrae
• raises and extends the neck

Question 20

What can be said about the ventricle of the turtle?

Answer 20

has a partially separated ventricle

Question 21

What can be said about the atrium of the turtle?

Answer 21

the heart is composed of fully separated left and right atria

Question 22

Describe the various components of blood circulation in the turtle.

Answer 22

• 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

Question 23

Which three large vessels emerge from the ventricle of the turtle?

Answer 23

right aortic arch, left aortic arch and pulmonary trunk

Question 24

Which vessel that emerges from the ventricle carries the most highly oxygenated blood in the turtle?

Answer 24

all the blood to the head and forelimbs originates from the right aortic arch and therefore carries the most highly oxygenated blood

Question 25

Which vessel that emerges from the ventricle receives primarily deoxygenated blood?

Answer 25

pulmonary trunk

Question 26

Function of the stomach?

Answer 26

secretes acids and enzymes to digest food

Question 27

Function of the liver?

Answer 27

detoxification, secretes bile

Question 28

Function of pancreas?

Answer 28

secretes enzymes and digestive juices into the intestine for further digestion

Question 29

Function of gall bladder?

Answer 29

storage of bile

Question 30

Function of caecum?

Answer 30

absorbs fluids and salts after digestion

Question 31

Function of spleen?

Answer 31

filter for blood, recycling red blood cells

Question 32

What would be the consequence of a blockage in the cystic duct?

Answer 32

gall bladder would become inflamed due to bile accumulating but not being able to exit this place of storage

Question 33

Which has a greater diameter and is shorter in length, the small intestine or the colon?

Answer 33

colon

Question 34

What is the cloaca?

Answer 34

the common opening for both the urogenital and digestive tracts

Question 35

Where does the gastric artery lead?

Answer 35

to the stomach

Question 36

Where does the coeliac artery lead?

Answer 36

to the stomach, pancreas, liver, small intestine, spleen, liver

Question 37

Which blood vessel would be most dangerous to cut?

Answer 37

Dorsal aorta since it is the origin of the right and left aortic arches (major vessels of the heart)

Question 38

Which sheets of muscles within the turtle's shell contract and relax to force air in and out of the lungs?

Answer 38

- diaphragmaticus and transverse abdominals compress the cavity to cause exhalation - glottis opens and obliques expand abdominal cavity for inhalation

Question 39

How can air pressure be altered to help the aspiration pump of the turtle?

Answer 39

moving limbs in and out of the shell

Question 40

What supports the trachea of the turtle? Function?

Answer 40

cartilaginous rings that help for support and allow the trachea to move and flex during breathing

Question 41

The trachea of the turtle bifurcates in the region of the heart into which structures?

Answer 41

left and right bronchi which pass into the lungs

Question 42

the bronchi of the turtle are in close association with which arteries?

Answer 42

pulmonary arteries

Question 43

Where are the lungs located in the turtle?

Answer 43

lungs adhere closely to the inner surface of the carapace

Question 44

What is the function of the septa in the lungs?

Answer 44

internal septa increase surface area for more efficient gas exchange

Question 45

Accessory bladders function?

Answer 45

paired vascularized sacs that are extra storage spaces for air and water

Question 46

Kidneys function

Answer 46

filter blood, balance body fluids, create urine

Question 47

Urethra function

Answer 47

drains urinary bladder

Question 48

Ovaries function

Answer 48

where developing eggs are located in the mother turtle

Question 49

What can be found in the inner surface of the ostia of the mother turtle?

Answer 49

has cilia lining the inner surface of the ostia which create currents to draw the eggs into it

Question 50

Oviduct function

Answer 50

transports mature egg from the ovary to the uterus of the mother

Question 51

Epididymis function

Answer 51

sperm from the testis are stored and mature here before passing into the vas deferens

Question 52

How is the penis divided in the turtle?

Answer 52

divided into two long ridges by a deep median urethral groove

Question 53

What are the multifidid cervicis in birds?

Answer 53

a complex group of small muscles which each surround a cervical vertebra, giving the neck flexibility

Question 54

Function of the longus colli in birds?

Answer 54

moves the neck down and forward

Question 55

Which two muscles in birds make up for 20-30% of their body weight? Why is this advantageous?

Answer 55

pectoralis and supracoracoides = flight muscles | allows for stronger flying and lift off the ground to escape from predators or travel long distances

Question 56

Which muscles are responsible for the upstroke and downstroke of the bird? Which is an adductor and abductor?

Answer 56

Pectoralis=contracts, downstroke, wing toward body, adductor Supracoracoide=contracts, upstroke, raises wing, abductor

Question 57

Describe the relative size of the axial muscles of the bird. What aspect of the bird skeleton allows for this reduction?

Answer 57

axial muscles are reduced since add extra weight for nothing | the keel is less weight and allows for better muscle attachment of flight muscles

Question 58

Where does air pass in the bird?

Answer 58

into oral cavity, tracea, through bronchci, to parabronchi (air tubes) in lungs

Question 59

What is the syrinx in birds?

Answer 59

sound producing organ formed by modifications of tracheal rings, bronchial half rings or both

Question 60

What kind of respiratory system do birds have?

Answer 60

system of air sacs (reservoirs of inhaled air) that have no blood vessels

Question 61

When does gas exchange occur in birds?

Answer 61

-exchange of air occurs on exhalation as air passes out of the air sacs back into the lungs

Question 62

What is the name of the membrane that contains the heart of the bird?

Answer 62

pericardium

Question 63

The heart of the bird has how many chambers?

Answer 63

four chambers: two thin walled atria and two large thick ventricles

Question 64

Due to the absence of teeth, what adaptations do birds have in their digestive tract to compensate for this?

Answer 64

- food storage in the crop | - mechanical digestion of food in gizzard (due to no teeth)

Question 65

In some birds, like pigeons, the esophagus has what type of special adaptation?

Answer 65

esophagus has out-pocketings that can be inflated and used to resonate sounds in courtship displays, used as visual signals, carry seeds

Question 66

What are the two parts of the stomach of birds?

Answer 66

proventriculus and gizzard

Question 67

What type of birds have well-developed gizzards?

Answer 67

seed eating birds

Question 68

Which is the largest organ in the bird?

Answer 68

liver

Question 69

What is strange about the kidneys of birds?

Answer 69

are irregularly shaped and have three lobes

Question 70

How is a kidney divided?

Answer 70

medulla and cortex

Question 71

With the exception of South American rheas, what do birds lack in their excretory system that was seen in turtles? How does this relate to nitrogenous waste that they produce?

Answer 71

birds do not have a urinary bladder for storage, probably due to the uric acid they produce is quite toxic and therefore cannot be stored inside their body (must be excreted right away)

Question 72

What is the role of the vasa deferentia in male birds?

Answer 72

carry sperm from the testes to the cloaca

Question 73

How many ovaries does a female bird have?

Answer 73

one functional ovary on the left side (right ovary is vestigial if present)

Question 74

In the snake, what are the two main extensor muscles? What are they used for?

Answer 74

- semispinalis and longissimus, held under high tension with ligaments - striking involves rapid extension of these muscles along parts of the body curve

Question 75

What do you notice about the general morphometrics of the snake viscera?

Answer 75

All viscera are elongated and flattened due to the snake's long and thin shape

Question 76

What is the purpose of the glottis in snakes?

Answer 76

can be protruded so that the airway is not obstructed as prey is swallowed

Question 77

What other digestive adaptations are seen in snake viscera?

Answer 77

- esophagus is very long and has more internal folds to swallow large and whole prey - peristaltic movement in esophagus

Question 78

Where is the heart located in snakes?

Answer 78

a third of the way down the body of the snake

Question 79

What is different about the lungs of the snake?

Answer 79

- have a single functional right lung and a small nonfunctional left lung - right lung extends more than half the length of the snake - also have a tracheal lung (vascularized sac that extends from the trachea and found next to the right lung)

Question 80

Function of the bird muscle called peroneus longii?

Answer 80

flexes the digits

Question 81

What is the order through which food passes through the digestive system of the bird?

Answer 81

1) esophagus 2) crop 3) proventriculus 4) gizzard 5) small intestine

Question 82

Match. Cystic duct, accessory bladders, duodenum, anus additional respiratory organ, connection between gall bladder and duodenum, part of small intestine closest to stomach, external opening of cloaca

Answer 82

cystic duct-connection between gall bladder and duodenum accessory bladders-additional respiratory organ duodenum-part of small intestine closest to stomach anus-external opening of cloaca