Vertebrate Form & Function Exam 3
Do faveoli or alveoli provide more surface area? What group has alveoli?
alveoli; mammals
What two pumps are involved in water ventilation with dual pumps? What are two methods of air ventilation?
1. buccal 2. operculum; -------------------------- 1. buccal 2. aspiration
What are two other methods of aquatic respiration?
1. buccopharyngeal epithelium 2. cloacal bursae
What are two important functions of bicarbonate ions?
1. buffer 2. prevent cavities by acidic environment
What are the two functions of gas bladders? Do we know which of these functions was their original function?
1. buoyancy control 2. gas exchange; no, it's not clear
Respiratory efficiency is enhanced by increasing the flow of gases into or across respiratory membranes (ventilation). What are three methods of ventilation covered in class? Which of these is useful only in small animals? What chordates or prechordates use this method?
1. cilia 2. ram ventilation 3. muscular ventilation; small animals use cilia; protochordates & some advanced vertebrates
**********Explain how an aspiration pump works. What two muscles contract to expand the size of the thorax? How does this affect air pressure within the thorax? How does this cause the lungs to inflate?
1. diaphragm 2. chest muscles; it decreases; the expansion of the thoracic cavity creates a vacuum sucking in air through the lungs
What two things are needed for gas exchange?
1. moist membrane 2. difference in partial pressures of gases on two sides of the membrane
What are the six parts of the alimentary canal that we discussed?
1. mouth 2. pharynx 3. esophagus 4. stomach 5. small intestine 6. large intestine
What are the three secretions of the salivary glands and what are the functions of each?
1. mucus - moisten food 2. bicarbonate ions - buffer 3. salivary amylase - breakdown of sugars
What are three things secreted by the stomach and give a function for each one.
1. pepsin (begins protein digestion) 2. HCl (provides the acid pH that pepsin needs 3. Intrinsic factors (needed for absorption of Vitamin B12)
What are two specialized modes of respiration used by turtles?
1. pulling water in and out of the pharynx using the hyoid apparatus 2. cloacal bursae
Give 4 examples of organisms using the cecum for fermentation.
1. rabbits 2. pigs 3. horses 4. koalas
What are the four "stomachs" called in a ruminant? Which of these is the true stomach? What are the other three derived from? What is the first stomach or chamber called? What is cud?
1. rumen (derived from esophagus) [first chamber] 2. reticulum (derived from esophagus) 3. omasum (derived from esophagus) 4. abomasum (true stomach) cud is regurgitated and chewed from the rumen
What are the four accessory structures?
1. salivary glands 2. liver 3. gall bladder 4. pancreas
What are the four mechanisms used for aerial respiration? Which of these are useful for both aquatic and aerial respiration?
1. skin 2. buccopharyngeal epithelium 3. nasal epithelium 4. lungs; skin & buccopharyngeal epithelium
What are two secondary uses of swim bladders?
1. sound production 2. hearing
What are two important factors influencing the efficiency of gas exchange?
1. surface area of the membrane 2. difference in partial pressures of the gases
What are the three types of muscular ventilation?
1. water ventilation with dual pumps 2. air ventilation w/ buccal pumps 3. air ventilation w/ aspiration pumps
What gland are the glands of venomous snakes derived from?
Duvernoy's gland
What causes deciduous teeth to be lost?
Growth of permanent teeth exerts pressure on the roots of the deciduous teeth cutting off nutrition and leading to their loss.
Why did external gills develop?
Internal gills were lost when life moved onto land; species that returned back to an aquatic existence therefore had to develop something new, hence external gills
*************Distinguish between polyphyodont and diphyodont and tell which group if animal each type is a characteristic of.
Polyphodont - teeth continuously replaced (lower vertebrates) diphyodont - two sets of teeth (mammals)
What is interesting about respiration in some cursorial mammals?
Running and breathing are coupled & animal breathing in synchrony with backwards/forwards movement of the viscera
What is the alimentary canal?
a tube extending from the mouth to the anus or cloaca and several accessory organs that release secretions into the tube
The spiracle is found in most cartilaginous fish. In which ones is it absent? In which ones does it not appear to have a respiratory function? In which ones does it have a respiratory function? Why is it believed to be functional in these organisms?
absent in holocephalians (ratfish); sharks; rays and skates; water enters the gill chambers when the mouth is buried in the sand
Where is Duvernoy's gland located and what does it secrete?
along posterior lip; produces secrous secretion
What part of the nervous system is primarily responsible for controlling digestion?
autonomic nervous system
What is a crop and what are three of its functions?
bag-like expansion of the esophagus; 1. store food 2. regurgitate food to feed young 3. produce nutritional substance that is fed to the young
What is the main function of salivary amylase?
begins breakdown of sugars
What are teeth believed to have been derived from?
bony armor
Are teeth believed to be derived from the dermis, epidermis, or both?
both
What kinds of fish usually lack air bladders?
bottom-dwelling fish & continuously-swimming fish (i.e. tuna & mackerel)
What part of the alimentary canal do salivary glands release their secretions in?
buccal cavity
*********Explain what a buccal pump is. Distinguish between 2 stroke and 4 stroke buccal pumps.
buccal cavity expands bringing air into the mouth, and contract to force air into the lungs; 2 stroke - air into buccal cavity (mouth) and lungs simultaneously 4 stroke - air is removed from the lungs in every other expansion
What system is responsible for distributing the oxygen to all parts of the body?
cardiovascular system
What does the esophagus do?
carries food from the pharynx to the stomach
What specialized structure serves as a respiratory structure for embryonic birds and reptiles? What forms this structure? What intermediate situation occurs about six hours before hatching?
chorioallantois; chorion & allantois the young pecks through the shell, and inhales air through air space, and breathes with lungs
In most vertebrates, what does the alimentary canal end in?
cloaca
***********Distinguish between the diaphragm of crocodilians and mammals. How do the two differ in how they function?
crocodilians - posthepatic septum (pulls liver backwards to assist respiration pump) mammals - no post hepatic diaphragm (acts directly on the pleural cavities)
What is the simplest and probably oldest mechanism for gas exchange? What vertebrates use this mechanism?
cutaneous respiration; amphibians & soft-shelled turtles
**************Distinguish between permanent and deciduous teeth. What are the two types of teeth?
deciduous - baby teeth; both are diphyodonts????
What is the hyoid apparatus derived from?
derived from branchial arches
The pharynx is part of what two systems?
digestive & repiratory
What are most teeth covered by?
enamel
What germ layer is the alimentary canal primarily derived from? What role does ectoderm play?
endoderm; form mouth and anus
What is the function of the epiglottis? Uvula?
epiglottis - prevents choking during swallowing by covering the glottis; uvula - prevents food and liquids from passing into nasal cavities
How do woodpeckers use lingual feeding?
extend their tongues into bark, and has barbs that allow it to rake prey into the mouth
Distinguish between ravioli, faveoli, and alveoli. What classes have faveoli?
faveoli - compartments within lung that open into central chamber alveoli - air sac located at ends of tiny branches of the trachea
What term is used for the breakdown of cellulose by microbial symbionts?
fermentation
What is a bolus?
food ball that passes the pharynx in the esophagus during swallowing
What is a general term for organisms using the four stomach approach to fermentation? The cecum?
four stomach - ruminants cecum - hindgut fermenters
What group uses cloacal bursae and is it an effective method?
freshwater turtles; yes, it increases time under water
What is the main function of the respiratory system?
gas exchange
How do most amphibians inflate their lungs?
gulp air via buccal pump
How do reptiles ventilate the lungs?
have paired lungs, use aspiration pump
**********Distinguish between heterodont and homodont dentition and tell which groups of animals each is usually found in.
heterodont - different teeth, different functions (mammals & some tetrapods) Homodont - same teeth (lower vertebrates)
What is the tongue derived from and what supports the tongue?
hypobranchial musculature; tongue supported by hyoid apparatus
Distinguish between internal and external respiration.
internal - exchange between blood and cells external - between blood and environment
What are some examples of organisms with external gills? Define neoteny.
larval bichers (actinopterygians), lungfish, amphibians; neoteny - adults with larval characteristics
What family depends almost entirely on cutaneous respiration? Why?
lungless salamanders (Plethodontidae); because they don't have lungs
**********Explain what an aspiration pump is. What groups use an aspiration pump?
lungs contract to suck air into them (acting as a vacuum); mammals, birds, and reptiles
What are the three ways in which teeth are attached to the jaw?
mammals - thecodont (sunk into sockets) snakes - acodont (attached to crest of bone with shallow sockets lizards - pleurodont (attached to side of jaw)
What organisms lack a cloaca?
mammals and some fishes
What groups have a secondary palate? What is its function?
mammals and some reptiles; separate nasal passages from the mouth
What is a symbiont?
microbial bacteria and protozoans in rumen used in vertebrates in place of enzymes used to digest cellulose
What is one way turtles ventilate the lungs?
moving limbs in and out of shell
Do birds have alveoli?
no
In snakes, is the entire lung functional in gas exchange? What structures are absent from the posterior portion of the snakes lung? What function does the posterior part of the lung play in ventilation?
no, only anterior portion has faveoli, posterior lacks it; vascularization absent; acts as a bellows
Do all animals need a cardiovascular system? Why?
no; small animals use diffusion
In organisms lacking four stomachs, what alternative site is used for fermentation of cellulose?
occurs in the hindgut (most often called the cecum) opposed to the foregut
What is the glottis?
opening into the respiratory system
Where is the gizzard located and how does it function? What groups have a gizzard?
part of the stomach; contains ingested sand or stone used to grind food; crocodilians and birds
How does the fermentation of cellulose affect atmospheric methane?
produces large amounts of methane
What is the rete mirabile and how does it work?
rete mirabile - counter-current capillary system. Lactic acid is present in the venous capillary, therefore preventing hemoglobin to bind to the oxygen. This free oxygen is transferred to the arterial capillary, in which it is then pushed to the bladder.
In what groups are the nasal passages connected to the mouth through opening in the palate?
rhipidistians and tetrapods
What are the exceptions to the rule that permanent teeth do not grow and are not replaced?
rodents/rabbits- incisors continuously grow from root as they wear down at the crown. Elephants-molars erupts sequentially during lifespan. [new molars erupt at the back of the jaw and push fwd as molars at front are worn away]
What made the development of lungs necessary?
terrestrial existence
In what group is a fleshy, mobile, tongue first formed?
tetrapods
What is lingual feeding?
tongue protracted to capture prey
Explain the location of the esophagus and trachea relative to one another.
trachea is ventral to the esophagus. (if you're looking at the person head-on, the trachea would be in front, and the esophagus behind it)
What are tusks? Give example of animals with tusks and the specific tooth that forms the tusk.
tusks = modified teeth narwhale - left upper incisor elephants - incisors walruses - canines
How are ruminants able to use nitrogenous waste as a nutrient?
use microorganisms that breakdown cellulose & use nitrogen in the form of ammonia to make cell proteins
If vertebrates are unable to digest cellulose how do cows live on grass?
via symbionts
What is peristalsis?
wave-like contractions of the smooth muscle in the walls of the canal
Are cilia retained in more advanced chordates? What is their function? What is the function of mucus? Where does the mucus come from?
yes; function to keep respiratory passages clean; mucus traps dirt and move it out of respiratory system; simple columnar epithelium with goblet cells
Are gas bladders and lungs believed to be homologous? What does homologous mean?
yes; homologous - share the same ancestor
Distinguish between physostomous and physoclistous swim bladders. In which fishes are physoclistous swim bladders usually found?
Physostomous - air bladder retains connection to digestive tract; Physoclistous - air bladder connection to digestive tract lost; ------------------------------------------ Physostomous - primitive Physoclistous - advanced fish
Why do conodonts cast some doubt on this view of the evolution of teeth?
Teeth are believed to be derived from bony armor,but because conodonts have teeth but no armor complicate this explanation
What is a cloaca?
a chamber receiving the digestive, excretory, and reproductive products
Are vertebrates able to digest cellulose?
no, they don't produce the necessary enzymes
What factor complicated ventilation in turtles?
their shell
What group has a hard and soft secondary palate?
mammals
What are the waste products of respiration?
water and CO2
Explain ram ventilation and tell what type of organisms it is found in.
water forced through gills; tuna and sharks
Give an example of an organism that uses both a dual pump and ram ventilation.
...
What is the function of oxygen?
ATP production
How do air sacs increase the efficiency of respiration in birds?
Air sacs act as bellows that allow airflow through lungs to be nearly unidirectional
How do anamniote embryos respire?
across the skin
What do birds have instead of alveoli?
air sacs