Exam Three Practice

What are the 3 ways that teeth can be attached to supporting bones and briefly explain each.

1. Thecodont teeth are generally found in reptiles and mammals. Their teeth are sunken into sockets within the supporting bone 2. Acrodont teeth are similar to thecodont teeth but the sockets are much shallower and found on the crest of the bone 3. Pleurodont teeth are found attached to the medial side of the bone

State and describe the two different types of ways in which adult amphibians are able to respire, with or without lungs.

Adult amphibians generally lose gills following metamorphosis, but cutaneous respiration still plays an important respiratory role if lungs are not present. Cutaneous respiration is respiration through the skin. But if lungs are present, they are ventilated by a four-stage buccal pump. The buccal cavity expands, which then draws in air through the nares. The glottis then opens, releasing spent air from the elastic lungs, which streams across the buccal cavity with little mixing and is vented through the nares. Next, the nares close and the buccal floor rises and forces air into the lungs. The glottis then closes, keeping the sir inside and the nares opens again with the buccal cavity sometimes oscillating repeatedly, flushing buccal cavity of residual air. This four-stage buccal pump allows for there to not be very much mixing of expelled and inhaled air.

Compare and contrast alveoli and faveoli in terms of function and structure, and name one vertebrate where each can be found.

Alveoli and faveoli both function in the respiratory tract in different vertebrates. They both are filled with capillaries to help ensure sufficient gas exchange in each vertebrate. With increasing surface area, the greater amount of gas exchange. Faveoli line the lung surface with capillaries within their walls and they open into a common chamber. They are more of an indentation in the lung wall. Faveoli can be found in many modern amphibians. Whereas alveoli are at the end of the highly branched tracheal respiratory system. The lungs are subdivided into alveoli with capillary blood vessels circulating within their walls. Alveoli can be found in mammals.

Compare the processes of respiration in adult amphibians versus birds.

Amphibians: Skin is used as the major respiratory organ. Lungs, if present, are ventilated by a four-stage buccal pump. Buccal cavity expansion draws fresh air in through the nares. Glottis opens, releasing spent air from elastic lungs, which streams across the buccal cavity with little mixing and is vented through the nares. Nares close and buccal floor rises, forcing air into the lung. Glottis closes, retaining the air inside and nares open again, with buccal cavity sometimes oscillating repeatedly, flushing buccal cavity of residual expired air. Birds: Lungs are almost exclusively serving as the respiratory organ. Two complete inhalation and exhalation cycles are required for air to pass through the system in unidirectional flow pattern through the lungs. Air first enters into trachea, down primary bronchus and either into the lungs or posterior air sacs as air sacs expand. As air sacs contract, air is forced to flow through the lungs. Air then enters anterior air sacs as they once again expand. Lastly, air exits trachea as air sacs contract again.

Discuss the differences between arteries and veins. Include details concerning direction of blood flow relative to the heart, which systems carry oxygen vs deoxygenated blood, high vs low pressure, and describe (location and tissue type) the 3 layers which enclose the central lumen of arteries and veins.

Arteries are vessels that carry blood away from the heart. They are under high pressure in order to help with this distribution of blood and oxygen throughout the body. Arteries carry oxygenated blood in all vessels EXCEPT the pulmonary arteries, which carry deoxygenated blood away from the heart, to the lungs where gas exchange can occur. Veins are vessels responsible for returning blood to the heart. They are low pressure and use one-way valves in order to prevent backflow. Veins carry deoxygenated blood in all vessels EXCEPT the pulmonary veins, which carry oxygenated blood form the lungs to the heart, which can then be pumped throughout the rest of the body through the arteries. Arteries and veins are made up of three layers. The most external/superficial layer is called the tunica adventitia and made up of fibrous connective tissue in both arteries and veins. The middle layer is known as the tunica media, made up of mostly elastic fibers in arteries (allows for stretching in high pressure) and made up of mostly smooth muscle in veins. The innermost layer which surrounds the central lumen is known as the tunica intima, made up of an endothelial lining.

__________ carry blood away from the heart, while __________ carry blood toward the heart, and __________ are the tiny vessels that lie between them.

Arteries; veins; capillaries

What is the name of the ventilatory mechanism that sucks in air by low pressure created around the lungs, rather than pushing air into the lung against a resisting force? a. Buccal pump b. Two-stroke buccal pump c. Four-stroke buccal pump d. Aspiration pump

Aspiration pump

Sinus venosus receives returning blood and is followed by the_______ o Atrium o Ventricle o Bulbus cordis o Encordial tub

Atrium

Which of the following is false? A. Amphibians rely heavily on cutaneous respiration B. In respiration, passive diffusion is random movement of molecules from areas of low partial pressure to areas of high partial pressure C. On a branchial arch, the lamellae on both the anterior and posterior faces of its septum is the holobranch, while a gill arch with lamellae on only one face is a hemibranch D. Faveoli, which are found in amphibians, line the lung surface with capillaries located within their walls and are pockets along the respiratory surface that open into a common chamber, while alveoli, which are in mammals are at the end of the branched tracheal system

B

Many actinopterygian fishes possess an elongate sac filled with gas. What is this called? A. Gas Sac B. Gas Pouch C. Gas Bladder D. Lungs

C

There are 3 regions of the stomach. __________ region marks transition between esophagus and stomach with predominantly mucous-secreting cells. Following the cardia, the region that contains mostly gastric glands and includes main body of stomach is called the ______. Lastly, the __________ region holds acid neutralizing glands at entrance to intestines.

Cardia, Fundus, Pylorus

Explain the 3 regions of the stomach by their histological differences

Cardia: this region of the stomach is only found in mammals, it transitions between the esophagus and stomach with predominantly mucous-secreting cells. Fundus: this region includes the main body of the stomach (sometimes grouped separately) and contains mostly gastric glands. Pylorus: the third region of the stomach located at the entrance to the intestines which holds acid neutralizing glands.

____ (Vitelline/Cardinal/Lateral Abdominal) veins unite into short common veins that open up into the sinus venosus. ____ (Vitelline/Subintestinal/Lateral abdominal) veins join iliac vein and branchial vein forming into the common cardinal

Cardinal, lateral abdominal

Reptilian hearts are generally divided into those found in chelonians (turtles) and squamates (lizards). Describe the anatomy of these hearts and how blood flows through them noting where oxygenated vs. deoxygenated blood is in the system. Also explain what happens in the heart during diving.

Chelonians and squamates have a reduced, but functional sinus venosus, completely divided atrium, and prominent AV valves. Conus arteriosus appears during early embryonic development, but forms trunks of the three large arteries (pulmonary arch, left systemic arch, and right systemic arch) in adults. They have a single chamber ventricle which has three interconnected compartments (cavum arteriosum, cavum venosum, and cavum pulmonale) separated by muscular ridges or connected via canals. Pulmonary vein blood flows to the left atrium, then to the cavum arteriosum through the interventricular canal and into the aortic arches. Blood that is filling the cavum venosum from the right atrium flows into the cavum pulmonale. Blood flow differs depending on if the organism is breathing or holding its breath. During breathing, most blood from the sinus venosus is directed to the pulmonary artery and most blood from the pulmonary vein is directed through the right and left systemic arches. During ventricular contraction, the ridge separating cavum pulmonale and cavum venosum largely separates compartments to direct blood flow. Asynchrony in ventricular contraction drives deoxygenated blood into the pulmonary artery before oxygenated blood is pushed through. During diving, the heart exhibits a right-to-left or cardiac shunt. During a cardiac shunt, the sphincter at the base of the pulmonary artery diverts deoxygenated blood into the left systemic arch. This causes oxygenated blood to flow into the right systemic arch.

Describe cutaneous respiration and give an example of a vertebrate that relies on this heavily for respiration.

Cutaneous respiration is respiration through the skin that can supplement breathing. The percentage of total gas exchange in cutaneous respiration varies considerably across vertebrates. Amphibians rely heavily on cutaneous respiration. Adult plethodontid salamanders lack lungs or gills. Frogs and salamanders have an increased surface area to allow for more cutaneous respiration. Mammals on the other hand, respire very little through the skin. When looking at percentages of total gas exchange, lungless salamanders have the highest at 100% oxygen uptake to carbon dioxide excretion; while humans have less than 10% with a higher CO2 excretion than O2 uptake.

What classifies blood as a connective tissue? A. Isolated and distinctive cell type B. A surrounding ground substance C. Extensive extracellular matrix D. All of the above

D

Describe each of the three common types of ventilatory pumps and give examples of organisms with each of the different muscular pumps.

Dual pump, pulse pump, and the aspiration pump all differ in the feeding and ventilation functions they are coupled with. In dual pumps, buccal cavities and opercular cavities work together to expand and contract to bring in water through oral valve, across the gill curtain and out through the opercular valve. There are two types of pulse pumps (two and four stroke pulse pumps). Two stroke system starts with the buccal cavity expanding, bringing fresh air into the mouth along with waste gas from the lungs. Gas is then forced into the lungs during the second stroke. The four stroke system brings waste gas into the mouth from the lungs during the first stroke. Expired gas is then expelled through the mouth, fresh air is drawn into the mouth via the nares, then the fourth stroke forces air into the lungs. The aspiration pump allows for ventilation and feeding to be separate in amniotes. The pump is composed of ribcage and diaphragm that lower the pressure in the lungs, allowing the air to be "sucked" into the lungs. Amphibians use the buccal pump system where larvae use the two stroke and amphibians (frogs) use the four stroke buccal pump. Dual pump is often seen in water breathing fish such as sharks while aspiration pumps is found in amniotes.

Describe two differences in tooth formation or development

Each individual tooth is separated into the crown—which is the part we can see—and the root—which is hidden in the gums. Teeth are capped with enamel or enameloid and have a cementum layer covering in the root. There is a dentine layer deep to enamel & cementum which forms the walls of the pulp cavity. Rodent and lagomorph teeth grow continuously with crowns being worn down and, and enamel on the convex side of teeth and dentine on the other. Teeth are similar throughout animals, but some—birds and turtles—lack teeth all together. Elephant molars erupt sequentially over time and replace anterior molars as they wear down. Teeth in general appear throughout the mouth and are replaced continuously in lower vertebrates, which is referred to as polyphyodont. Some tetrapods, however, have heterodont teeth that are replaced only once. Concerning teeth supporting bones, the three ways include thecodont teeth, acrodont teeth, and pleurodont teeth. Archosaurian reptiles and mammals have thecodont teeth sunken into sockets within the bone. Acrodont teeth have shallow sockets with teeth attached to the crest of the bone. Pleurodont teeth attach to the medial side of bone.

There are different elements that blood of composed of, including ___________________, which is have nuclei but not in mammals, _______________, which is the major oxygen transport molecule contained by red blood cells, _____________________, which defends the body from infection and disease, and, finally, _______________, which release factors that result in clot formation.

Erythrocytes (Red blood cells); Hemoglobin; Leucocytes (white blood cells); Platelets

What is the difference between faveoli and alveoli? Where might each be found?

Falveoli are pockets in the respiratory surface that collectively empty into a common chamber. These are found in most amphibians. Alveoli are pockets at the terminal portion of the bronchial tree in the lungs. These can be found in mammals.

Which venous vessel(s) of the systemic system is responsible for draining the blood of the liver? a. Renal portal vein b. Hepatic portal vein c. Renal portal artery d. Hepatic portal artery

Hepatic portal vein

A __________ is a branchial arch that contains lamellae on both anterior and posterior faces of its septum. A __________ is a gill arch with lamellae on only one face.

Holobranch, hemibranch

Teeth are unique among vertebrate animals and are usually capped with enamel or enameloid. When teeth are similar in general appearance throughout the animals mouth is called, _________. Some tetrapods have teeth that do not look similar called, __________. In lower vertebrates, teeth are replaced continuously, __________ teeth, and when they are only replaced once is, __________ teeth.

Homodont; heterodont; polyphyodonty; diphyodont

Describe the anatomy and blood flow of the mammalian heart

Mammals have hearts that are divided into 4 chambers that arise from the atrium and ventricles of fish. The four chambers are the right atrium, right ventricle, left atrium, and left ventricle. Blood first enters the heart through the inferior and superior vena cava and empties the oxygen-poor blood into the right atrium. The atrium contracts and sends the blood into the right ventricle through the tricuspid valve. From the right atrium, the blood is pumped into the lungs through the pulmonary artery where it is oxygenated. After the blood is oxygenated, it is then brought back to the heart via the pulmonary vein into the left atrium. The blood then moves to the left ventricle through the mitral value. Lastly the heart pumps one last time sending the oxygen rich blood front the left ventricle through the aortic valve into the aorta and out to the rest of the body.

During embryonic development of the heart the epimyocardium gives rise to the _____________ while the endocardial tubes form the ______________.

Myocardium; endocardium

What are the primitive number of aortic arches and branchial arches in ostracoderms, lampreys, hagfishes, and sharks, what is the embryonic pattern and what becomes of these?

Ostacoderms had up to 10 branchial arches, lamprey have 8 pairs of aortic arches, hagfish had 15 and some sharks have 10 or 12 pairs. Only up to 6 pairs appear during embryonic development and 6 is the basic embryonic pattern. In these fishes the aortic arches divide into capillary beds within the gills. - Make sure to specify that the 6 pairs is for more gnathostomes

Describe the pathway of oxygenated and deoxygenated blood in the four chambered heart

Oxygenated blood: flows from lungs into left atrium via pulmonary artery, then to left ventricle and out to systemic circulation via the aortic arch Deoxygenated blood: flows from systemic circulation into the right atrium via precavae, then to the right ventricle and out to the lungs via the pulmonary artery

Primitive teleosts have a ____ (physotomous/physocllstous) swim bladder that ____ (has/lacks) a connection between the digestive tract and the pneumatic tube. Modern teleosts have a ____ (physotomous/physocllstous) swim bladder that ____ (has/lacks) a connection to the digestive tract

Physostomous; has; physoclystous; lacks

Blood is comprised of plasma and formed elements. Briefly describe what plasma is and each of the 4 formed elements.

Plasma - fluid component of blood Formed Elements: 1. Erythrocytes (RBCs) - contain hemoglobin, which is used to transport oxygen, mammals are the only group with anucleate red blood cells 2. Hemoglobin - molecule responsible for the majority of oxygen transport, it is contained within red blood cells 3. Leucocytes (WBCs) - also known as white blood cells, defend the body from infection and disease 4. Platelets - release factors which result in the formation of a clot

Which formed element releases factors that result in the formation of a clot? a. Erythrocytes b. Platelets c. Leukocytes d. Plasma

Platelets

___________ release factors that result in the formation of a clot.

Platelets

Which artery listed below does NOT carry oxygenated blood away from the heart? a. Cortaid artery b. Pulmonary artery c. Femoral artery d. Renal artery

Pulmonary artery

Passive diffusion of molecules via _________________ from areas of _______ to areas of ________ partial pressure

Random diffusion; high; low

Mammals lack which of the following circulatory system components? a. Renal portal system b. Hepatic portal system c. Systemic circuit system d. Pulmonary circuit

Renal portal system

Which of the following circulatory system parts are NOT found in mammals? a. Hepatic portal system b. Renal portal system c. Pulmonary circuit d. Systemic circuit

Renal portal system

Pharyngeal slits never become functional after birth in which group of animals? a. Bony Fishes b. Reptiles c. Amphibians d. Tetrapods

Reptiles

____________ is the delivery of O2 to tissues & removal of waste products. More specifically, ____________ involves gas exchange between the blood and deep body tissues, and ___________ involves gas exchange between the environment and blood via respiratory surface.

Respiration; Internal Respiration; External Respiration

With regard to the cardiovascular system, explain the embryonic development and describe the embryonic heart.

The cardiovascular system arise within the embryonic mesoderm. Most blood vessels are started with clusters of mesoderm cells called blood islands. These blood islands in the embryo merge to form a vascular network. The embryonic heart is tubular and has four chambers, the sinus venosus receives oxygen poor blood and then goes into the atrium, then ventricle and finally the bulbus cordis.

Explain the path that blood takes while returning to the heart (include all the prominent veins) in generalized primitive vertebrate

The common cardinal vein receives blood that is returning from the preliminary region of the body and the posterior cardinal vein receives blood that is returning from the subsequent region of the body. The subclavian vein drains into the common cardinal veins from anterior appendages and the lateral abdominal vein drains into common cardinal vein from lateral body wall and posterior appendages. Portal systems travel between capillaries without exchanging blood through the heart throughout their course. The hepatic portal system moves from the digestive tract through the hepatic portal vein to the liver. The renal portal system travels from the tail and hindlimb through the renal portal veins to the kidneys

Name and describe the 3 sets of paired veins that form the systemic system in early development. Be sure to include information on how these sets developed.

The first set, the vitelline veins, are amongst the first vessels to appear in the developing embryo and develop over the yolk and follow the yolk stalk into the body, forming the yolk sac. They then turn anteriorly, continuing along gut and eventually enter the sinus venosus. The liver primordial grows into the vitelline veins. The second are the cardinal veins, including both anterior and posterior cardinal veins. During development they will merge to form short common cardinal veins, which open into the sinus venosus. Anterior cardinals will develop as vessels receiving tributaries from the brain, cranium & neck. Posterior cardinals will develop primarily as vessels of the embryonic kidneys The final set is made up of the lateral abdominal veins. Lateral abdominal veins will join iliac vein & brachial vein to enter the common cardinal as the subclavian vein. Lateral abdominal veins are usually absent in fishes, and either absent or merged in tetrapods. In tetrapods that have the lateral abdominal veins entering the liver, the subclavian vein will return separately to the heart.

Describe the heart in the cardiovascular system including how it appears/works in fishes, amphibians, reptiles, birds, and mammals.

The heart lies within the pericardial cavity and lined with epithelial membrane called pericardium. The heart more than likely began as a contractile vessel. The embryonic fish heart consists of four chambers: sinus venosus, atrium, ventricle, and bulbous cordis (referred to as conus arteriosus in adults). Blood flows from the sinus venosus to the atrium to the ventricle and finally into the bulbus cordis where it exits the heart into the ventral aorta. Between the sinus venous and atrium is a valve called the sinoatrial valve and between the atrium and ventricle, the atrioventricular valve. Hagfish have a branchial heart and accessory "hearts". The branchial heart includes a sinus venosus, atrium, ventricle, and arguably a bulbus arteriosus. Accessory "hearts" lack cardiac muscle but do contract. Lamprey heart contains all 4 chambers with one-way valves between chambers. Chondrichthyan and bony fishes hearts also have typical 4 chambers with one-way valves. Lungfishes have a modified heart with a partially divided atrium and ventricle. The atrium is divided by interatrial septum and the ventricle by interventricular septum. Amphibian heart structure varies along with their respiratory modes. In individuals with functional lungs, the heart includes a sinus venosus, right and left atrium divided by an anatomically complete interatrial septum, a ventricle, and a conus arteriosus. Turtles, tortoises, snakes, and lizards have a reduced but functional sinus venosus, divided atrium, and AV valves. The ventricle is a single chamber but with three interconnected compartments. Crocodiles have hearts similar to other reptiles, but their ventricle is divided by complete interventricular septum and foramen of Panizza connects the right and left systematic arches. Birds and mammals have four chambered hearts arising from the atrium and ventricles of fishes. Oxygenated blood flows from the lungs into left atrium via pulmonary artery, then to the left ventricle and out to systematic circulation via the aortic arch.

Explain the differences between small and large arteries. What are the functions of each?

The main difference between large and small arteries is that large arteries have a large amount of elastic fibers in their walls. Small arteries on the other hand, have almost no elastic fibers. Due to this, they have different functions. Large arteries are used to absorb and distribute the sudden surge of blood through them when the heart beats. Small arteries distribute this volume smoothly into the arterioles. Arterioles then distribute the blood into the local tissues

Compare the structure of a typical mammalian heart to that of a crocodile. Be sure to highlight the differences in chambers, arteries/veins, etc. Also map the flow of blood in the both hearts.

The mammalian heart is four-chambered with complete separation between both atria and ventricles. The complete separation of the chambers means there is no cardiac shunting in the mammalian heart. Mammilian hearts also have a single aortic trunk branching off the top of the heart. Blood flow follows a single path from entry to exit from the heart. Deoxygenated blood enters the right atrium via the pre- and postcava. It then enters the right ventricle where is passes through the pulmonary artery into the lungs. Oxygenated blood returns to the heart via the pulmonary vein into the left atrium. From the left atrium, the blood enters the left ventricle where it is forced through the aortic arch and into the body. The crocodilian heart is similar to the mammalian heart because of its four chambers. It also has complete interventricular and interatrial septa. The major difference is the presence of the foramen of Panizza in the crocodilian heart. This is the small connection between the left and right systematic arches. These arches could be compared to the aortic arch in mammals. Blood flow in the crocodilian heart follows a similar path to the mammalian heart. Deoxygenated blood enters the right atrium and flows into the right ventricle. It is then forced into the pulmonary artery where it flows through the lungs. The oxygenated blood reenters the heart via the pulmonary veins that empty into the left atrium. The left atrium empties into the left ventricle where the strong contraction forces the blood into the right systematic arch where it flows to the body. The also blood flows through the foramen of Panizza into the left systematic arch where is flows to the body. This process of the blood not following a single set path is called cardiac shunting

Which of the following statements is incorrect? A. The posterior mesenteric supplies most of the small intestine B. In the lamprey heart the sinoatrial (SA) valve lies between the sinus venous and the atrium C. In birds the left systemic arch does not develop D. In mammals the renal portal vein is absen

The posterior mesenteric supplies most of the small intestine

Describe and explain the structure of the stomach using the three different regions and their function/structure.

The stomach contains folds called rugae to increase surface area for nutrient absorption. The first region of the stomach which is only found in mammals is the cardia. This is between the esophagus and stomach where there are mucous-secreting cells. The next region is the fundus which is the main body of the stomach. The fundus contains gastric glands which secrete gastric mucous to break down food. The last region is the pylorus which is at the entrance of the intestines and holds acid neutralizing glands.

Name and explain the parts of components of the stomach

The stomach wall shows folds called rugae (when not distended with food). The cardia region of the stomach is only in mammals and it marks the transition between the esophagus and the stomach with mucus secreting cells. The fundus is the main region of the body and holds mainly gastric glands. The Pylorus region is the bottom of the stomach, before exiting into the small intestine. The pylorus region holds acid neutralizing glands.

In the cardiovascular system, there are three principle types of blood vessel. Name the three types of blood vessels, and, if applicable, describe the direction of blood flow, oxygen levels, blood pressure, and the tubular walls seen in blood vessels.

The three blood vessels present in the cardiovascular system are arteries, veins, and capillaries. Arteries carry blood away from the heart. Most arteries carry blood high in oxygen, with the exception of the pulmonary artery. Veins carry blood toward the heart. Most veins carry blood low in oxygen, except for the pulmonary vein. Capillaries are tiny vessels that lie between arteries and veins. Capillaries lack tunica media and tunica adventitia, with only the endothelial wall of the tunica intima remaining. Arteries and veins have tubular walls organized into 3 different layers enclosing a central lumen. The center most layer including endothelial lining is the tunica intima. The middle layer is the tunica media. In arteries, the tunica media contains some smooth muscle, but is mostly composed of elastic fibers. In veins, the tunica media contains smooth muscle with no elastic. The superficial most layer is the tunica adventitia, which is comprised of mostly fibrous connective tissue. Arteries contain more elastic fibers to accommodate to the high pressure put on them to transport blood throughout the body, while the veins have no elastic because they have a low pressure of blood flow.

What are the three sets of paired veins that form in early development and unique features of each pair?

The three pairs are the Vitelline veins, Cardinal veins, and Lateral abdominal veins. Vitelline veins are among the first vessels to appear in the embryo. They arise over the yolk and follow the yolk stalk into the body forming the yolk sac. The liver primordial grows in the vitelline veins. The cardinal veins include the anterior and posterior cardinal veins which unite into short common cardinal veins which opens into the sinus venosus. Anterior cardinals develop as vessels receiving tributaries from the brain, cranium & neck. Posterior cardinals develop primarily as vessels of the embryonic kidneys. Lateral abdominal veins Join iliac vein & brachial vein to enter the common cardinal as the subclavian vein. These veins are present in fishes but usually merged or absent in tetrapods.

The digestive tract consists of 3 regions. One of the regions is also then divided into 4 subsequent regions. Name the 3 main regions of the digestive tract and describe what each regions consists of, including names the 4 subsequent regions of the correct digestive region.

The three regions of the digestive tract is the buccal cavity, pharynx, and the alimentary canal. The buccal cavity is the oral opening and contains the teeth, tongue, and palate (primary and secondary). The pharynx is a corridor for food and air passage. The Alimentary canal consists of 4 more subsequent regions: esophagus, stomach, and small intestines, and large intestines

Name and describe the 3 sets of paired veins which form the systemic system in early development. Include how these veins arise, and what they form.

The three sets of paired veins that form this system are vitelline veins, cardinal veins, and lateral abdominal veins. Vitelline veins are among the first vessels to appear in the embryo. They arise over the yolk and follow the stalk into the body to form the yolk sac. The liver primordial grows in these veins. Cardinal veins are split into the anterior and posterior cardinal veins. These two branches untie to form short common cardinal veins, which open up into the sinus venosus. The anterior cardinals develop as vessels and receive tributaries from the brain, cranium, and neck, whereas the posterior cardinals develop as vessels of the embryonic kidneys. The lateral abdominal veins are present in fishes, and are usually merged or absent in tetrapods. These join the iliac vein and branchial vein to enter the common cardinal as the subclavian vein. This vein then returns separately to the heart in tetrapods with lateral abdominal veins entering the liver

List and explain the three layers enclosing a central lumen in arteries and veins

The tunica intima is the most inner layer which includes the endothelial lining. The tunica media is the middle layer that when found in arteries consists of some smooth muscle but mainly elastic fibers and when found in veins consists of smooth muscle and very little elastic fibers. The tunica adventitia is the most superficial layer consisting of primarily fibrous connective tissue.

What type of ventilatory mechanism do most water breathing fish use? Describe the steps of this ventilatory mechanism. How does the pressure of the opercular cavity compare to the buccal cavity? What does this prevent?

The ventilatory mechanism that most fish use is the Dual pump. The Dual pump mechanism occurs in two steps. The first step is the suction phase. During the suction phase the buccal and opercular cavity expand. This expansion lowers the pressure in both the opercular and buccal cavity. This reduction in pressure draws water in through the oral valve and into the buccal and opercular cavity. The second step is the force phase. During the force phase the floor of the buccal and opercular cavity rise increasing the pressure and decreasing the volume in both the buccal and opercular cavity. Due to the increase in pressure and decrease in volume of the cavity water is forced through the opercular valve and out of the fish. The opercular cavities pressure is always below that of the buccal cavity to prevent water from flowing in the wrong direction. Be sure to mention when the opercular and oral valves are open and closed, however.

Name three different ways in which teeth can be attached to the supporting bone in vertebrates. Describe the three different ways.

Thecodont, Acrodont, Pleurodont. Thecodont teeth are sunken into sockets within the bone. Acrodont teeth are attached to the crest of the bone. Pleurodont teeth are attached to the medial side of the bone.

Teeth are attached to supporting bone in three different ways. ___________ (Thecodont/Acrodont/Pleurodont) teeth are sunken into sockets within the bone. While ___________ (thecodont/acrodont/pleurodont) teeth attach to the medial side of bone. And lastly, __________ (thecodont/acrodont/pleurodont) teeth have shallow sockets with teeth attached to the crest of the bone.

Thecodont, pleurodont, acrodont

Archosaurian reptiles and mammals have ____ (Thecodont/Acrodont/Pleurodont) teeth which are sunken into sockets within the bone. ____ (Thecodont/Acrodont/Pleurodont) teeth have shallow sockets with teeth attached to the crest of the bone. ____ (Thecodont/Acrodont/Pleurodont) teeth attach to the medial side of bone

Thecodont; Acrodont; Pleurodont

Teeth are connected to suportting bones in ____ different ways. ______ teeth are sunken into sockets within the bone. _____ teeth have shallow sockets while attached to the crest of bone. _____ teeth are attached to the medial side of bone

Three; Thecodont; Acrodont; Pleurodont

Which of these is NOT one of the three regions of the digestive tract? a. Pharynx b. Buccal Cavity c. Allimentary Canal d. Trachea

Trachea

Mammalian respiration occurs through exchange sites at the end of a series of repeatedly divided pathways. The first and largest structure of this series is the ___________ (bronchioles, alveoli, trachea, bronchi). The next structure, moving through the respiratory pathway, is the ___________ (bronchioles, alveoli, trachea, bronchi). The respiratory pathway then further divides into structures known as ___________ (bronchioles, alveoli, trachea, bronchi). The terminating, blind-ended compartments where gas exchange takes place is known as the ___________ (bronchioles, alveoli, trachea, bronchi).

Trachea; bronchi; bronchioles; alveaoli

Of the layers of arteries and veins, which one lies most superficial and is composed of fibrous connective tissue? A. Tunica media B. Tunica intima C. Tunica lateralis D. Tunica adventitia

Tunica adventitia

Which of the following is not a component of the tubular walls of arteries and veins? a. Tunica intima b. Tunica media c. Tunica exteria d. Tunica adventitia

Tunica exteria

Which blood vessels carry blood toward the heart? a. Arteries b. Veins c. Capillaries d. Arterioles

Veins

A bird eats some seed and it goes down its digestive tract. Explain how the seed would travel through the various anatomical regions of the bird.

When the bird swallows the seed it will go down its esophagus. It then joins the thin-walled glandular section of the stomach called the proventriculus. From the proventriculus it goes to a region called the gizzard. From the gizzard it moves to the duodenum then the illeum. From there it moves to the ceca or large intestine - Also the crop