Lecture 1- Introduction And Vertebrate Body Plan Flashcards
(119 cards)
1
Q
List the three subphylum of the phylum Chordata.
A
> subphylum Cephalochordata
> subphylum Urochordata
> subphylum Vertebrata
2
Q
List the major characteristics of the subphylum Cephalochordata.
A
> these include the cephalochordates or lancets (e.g., amphioxous, genus Branchiostomata (
3
Q
List the characteristics of the subphylum Urochordata.
A
> these include the ascidians (sea squirts), thaliaceans, and larva cleans, all of which are small marine organisms
4
Q
List the characteristics of the subphylum Vertebrata.
A
> as the name implies, these include all the vertebrates– past and present. This includes YOU.
5
Q
The subphylum Vertebrata is divided into which two superclasses?
A
> Pisces: >>> this superclass includes all of the fishes, Bothe extant and extinct
> Tetrapods: >>> this superclass includes all the tetrapods, both extant and extinct
6
Q
List the characteristics of the members belonging to the class Agnatha (subphylum Pisces).
A
> Class Agnatha: >>> this class is made up of both extinct and extant fishes, all of which share the same lack of jaws and paired appendages. Living members of this class include the marine hagfishes and the marine freshwater lampreys
7
Q
List the characteristics of the members belonging to the class Acanthodii (subphylum Pisces).
A
> class Acanthodii: >>> this class includes ONLY extinct members and is represented by the "spiny sharks", which are spiny but are not sharks
> > > members of this class along with those of the class Placodermi are sometimes referred to as gnathostomes, referring to the fact that they were the first vertebrates with jaws
> > > note, however, that all vertebrates other than agnathans possess jaws
8
Q
List the characteristics of the members belonging to the class Placodermi (subphylum Pisces).
A
> class Placodermi: >>> this class includes early jawed fishes with paired fins. They are all extinct but included both small species as well as very large representatives
9
Q
List the characteristics of the members belonging to the class Chondrichthyes (subphylum Pisces).
A
> class Chondrichthyes: >>> members of this class lack the ability to form bone
> > > their skeletal systems are made up entirely of cartilage
> > > in addition to extinct forms, this class includes modern sharks, skates, rays, and related specie
10
Q
List the characteristics of the members belonging to the class Osteichthyes (subphylum Pisces).
A
> class Osteichthyes: >>>this class includes the largest number of species of fishes
> > > the class name refers to the fact these fishes have a skeletal system of bone, although many of them still retain a considerable amount of cartilage within their skeletal system
11
Q
List the characteristics of the members belonging to the class Amphibian (subphylum Tetrapods).
A
> class Amphibia: >>> this class includes extinct amphibian species as well as modern frogs, toads, salamanders, and caecilians
12
Q
List the characteristics of the members belonging to the class Reptilia (subphylum Tetrapods).
A
> class Reptilia: >>> members of this class includes not only extant lizards, snakes, turtles, crocodilians, and related species, but also the extinct dinosaurs, flying reptiles such as pterosaurs, and marine reptiles such as plesiosaurs
13
Q
List the characteristics of the members belonging to the class Aves (subphylum Tetrapods).
A
> class Aves: >>> ALL birds, both extinct and extant, belong to this class. The major characteristic is the presence of feathers
14
Q
List the characteristics of the members belonging to the class Mammalia (subphylum Tetrapods).
A
> class Mammalian: >>>this class includes ALL mammals, both extinct and extant. Major characteristics of this class include the presence of hair and mammary glands
15
Q
What are the four anatomical features that an animal must possess in order to be included in the phylum Chordata?
A
> dorsal hollow nerve cord
pharyngeal “gill” slits, arches, and pouches
a notochord
post-anal tail
16
Q
True or False: all of the four anatomical features needed to be included in the phylum Chordata must be present in the adult form?
A
> False
> these features do not have to be present in the adult, BUT they must at least be present in the embryo or larva
» adult sea squirts have notochord in the tail in the larval form, but it is lost in the sessile adults
»humans would appear to have lost the notochord in the adult, as well as the pharyngeal gill slits, but remnants are still present
17
Q
What structure represents the future Britain and spinal cord?
A
> the dorsal hollow nerve cord
» it arises embryo logically as a hollow tube located dorsal to the notochord
» the hollow nature of the embryonic neural tube is retained in all adult vertebrates in the form of hollow cavities within the brain (ventricles) and spinal cord (spinal canal)
» note that in many invertebrates, the nervous system consists of a solid ventral nerve cord
18
Q
The pharynx is what part of the gut tube?
A
> the pharynx is the cranial portion of the gut tube
19
Q
All chordate embryos are characterized by the presence of what structures?
A
> pharyngeal pouches (also called branchial punches)
» often, at least in the embryo, these punches may open to the exterior as pharyngeal slits
» in many chordates, such as fishes, these slits persist in the adult as gill slits
» these slits general connect the interior of the pharynx with the external environment of the organism, but in the non-vertebrate chordates, such as amphioxus, the gill slits open into the specialized chamber, the atrium, which then opens to the exterior via an opening call the atriopore
20
Q
What is a pharyngeal arch?
A
> The portion of the pharyngeal wall between a pair of adjacent gill pouches
21
Q
Each pharyngeal arch consists of what?
A
> a pharyngeal skeletal element
branchiomeric muscles
cranial nerve branches
an aortic arch
22
Q
True or False: a pharyngeal arch is also located in front of the first pharyngeal pouch and behind the last pouch
A
> true
23
Q
The first pharyngeal arch is also known as what?
A
> mandibular arch
24
Q
The second pharyngeal arch is also known as what?
A
> hyoid arch
25
The first pair of pharyngeal pouches, into which the first pair of gill slits open, become what structures In tetrapods?
> auditory tubes and middle ear cavities
26
The second pair of pharyngeal pouches form the pouches of what structures in mammals?
> the palatine tonsils
27
The primitive vertebrate pharynx was a device used for doing what?
> the primitive vertebrate pharynx as a device for filtering food out of a respiratory water stream
28
External gills develop as outgrowths from which structures?
> external gills develop as outgrowths from pharyngeal arches
29
True or False: The lungs arise from a mid ventral evagination of the pharyngeal floor?
> true
30
Oxygen may be obtained from the water flowing through the pharyngeal gill slits if what?
> if the walls of the pharyngeal gill slits are highly vascularized
31
While many organisms use the pharyngeal gill slits for respiration, what was their original function?
> the original function of the pharyngeal gill slits was for filter feeding
>>> water bearing microscopic food particles (plankton) moves from the exterior through the mouth and then through the gill slits to the atrium or to the exterior
>>> microscopic food particles are the trapped by the gill slits and made available to the organism
32
This structure is formed in all chordates and serves as a primitive skeletal structure?
> notochord
33
Summarize the functions of the notochord.
> the notochord is formed in all chordates and serves as a primitive skeletal structure
>>> the notochord imbibes water and serves as a hydrostatic skeleton, especially for the embryo
>>>>> dessication during the embryonic development is detrimental partly because of the collapse of the notochord
>>> the notochord consists of a rod of living cells located immediately ventral to the dorsal hollow nerve cord and dorsal to the gut tube
>>>>> the cells of the notochord superficially resemble cartilage, but it is not cartilage, nor is it considered to be a true connective tissue
>>>in some lower vertebrates such as the agnathans (e.g., lampreys) the notochord is the only axial support system
>>> in adult modern birds,, reptiles, and mammals, the notochord is almost or completely obliterated
>>> its remnants may be found in the intervertebral discs of mammals and reptiles as the nucleus pulposus
>>>the notochord is also responsible (as amorphous chordates orders) for initiating the formation of the central nervous system, which is always located dorsal to the notochord
34
The vertebral column is only found in ________?
> vertebrates
35
Summarize the functions of the vertebral column
> the vertebral column is only found in vertebrates
>>> it is a series of irregularly-shaped elements (made of cartilage and/or bone) that surround and protect the nerve cord and also provide a flexible but strong axial support
>>> in terrestrial vertebrates the vertebral column is more important as an axial support system because it is more rigid than the notochord and can better resist the effects of gravity
>>> conversely, the notochord is retained to some degree in many aquatic vertebrates, such as fishes and salamanders, because it is more flexible and, therefore, more useful for undulating swimming movements
36
Name the major areas of the vertebrate body.
> head
> trunk
> tail
> appendages
37
Summarize the head of the vertebrate body.
> contains a concentration of sense organ (cephalization) and is part of the body usually to enter a new milieu
38
Summarize the trunk of the vertebrate body.
> contains most of the viscera and serves as a central support for the appendages
> the head and trunk may be connected by a slender stalk, the neck
39
Summarize the tail of the vertebrate body.
> the tail begins at the caudal opening of the digestive tube, the anus
> the tail is the main organ of locomotion in fishes, salamanders, and tadpoles
> some vertebrates lose their tail in the adult form
>>> I.e., frogs, primates, and birds
>>> but it is present in the embryo
```
> other uses for the tail
>>> attachment or grasping (prehensile)
>>> flyswatter (I.e., horses)
>>> balance (I.e., kangaroos)
>>> defense (I.e., some prehistoric dinosaurs)
```
40
Summarize the appendages of the vertebrate body.
> all modern vertebrates other than cyclosomes have two pairs of appendages
>>> they may be highly modified or secondarily lost (I.e., snakes)
>>> the appendages of a whale, bird, and human may have enormous superficial differences, but their basic anatomical plan, as we shall see, is identical
41
What are some other characteristics outside of the head, neck, tail, and appendages that are shared with invertebrate groups?
```
> cephalization
> complete digestive tract
> bilateral symmetry
> metharism
> triploblasty
> eucoelomate body cavity
> closed circulatory system
> dueterostomy
```
42
Bilateral symmetry refers to what?
> bilateral symmetry refers to a body organization such that the body may be divided into right and left halves that are more-or-less mirror images of each other, at least externally
>>> note that some aspects of internal anatomy are symmetrical in the adult but often have bilateral symmetry in the embryo
43
Bilateral symmetry may be seen as being organized around _______ axes. These axes intersect one another and are oriented ________ to each other.
> three
| > perpendicular
44
How many axes are used to describe the vertebrate body plan?
> three
45
What are the three axes that intersect with each other?
> cranial caudal axis (aka, vertical axis)
> dorsal/ventral axis (aka, Sagittal axis or anterior/posterior axis)
> left/ right axis
** these terms refer to quadrupedal organisms, but are also used, sometimes with minor modifications, for bipedal organisms, such as humans
46
The cranial/caudal axis is also referred to as what?
> vertical axis
47
The dorsal/ventral axis is also refereed to as what?
> sagittal axis
OR
> anterior/posterior axis
48
Two intersecting axes define a ______ dimensional plane
> two
49
We can have three different combinations of any two of the three axes that define bilateral symmetry; therefore we have three planes. What are they?
> Sagittal plane (includes midsagittal and parasagittal planes)
>>> defined by the cranial/ caudal and anterior/posterior axes
> frontal (coronal) plane
>>> defined by the cranial/caudal and left/ right axes
> transverse (cross-section) plane
>>> defined by the dorsal/ventral and left/right axes
50
Sagittal and mid-sagittal are often used synonymously and refer to a plane that divides the body into equal _________ and ________ halves?
> right
| > left
51
A parasagittal plane is any plane _______ to the mid-sagittal plane?
> parallel
52
True or False: all body movements occur within a specific plane or combination of planes around a specific axis or combination of axes?
> true
53
List the typical movements associated with the body.
```
> flexion
> extension
> ABduction
> ADduction
> rotation
```
54
Summarize flexion.
> this is a bending movement that takes place in a Sagittal plane around a left/right axis
> flexion usually brings two parts closer together
> the prenatal position of the fetus is a position of total body flexion
55
Summarize extension.
> this movement results in a straightening out of a bent part
> extension takes place in a Sagittal plane around a left/right axis
56
Summarize ABduction.
> this refers to a movement apart from the midline
| > ABduction takes place in a frontal plane around sagittal (anterior/posterior) axis
57
Summarize ADduction.
> this refers to a movement toward the midline
| > ADduction takes place in a frontal plane around a sagittal (anterior/posterior) axis
58
Summarize rotation.
> this refers o a movement of a part of the body around its long axis (cranial/caudal axis) in a transverse plane
59
The vertebrate body can be viewed as a pair of __________, one inserted inside the other
> tubes
60
What are the two tubes of the vertebrate body?
> outer somatic tube
| > inner splanchnic tube
61
What is the function of the outer somatic tube?
> the outer tube interacts with the external environment and consists of:
>>> skin
>>> skeletal muscle
> the somatic tube allows the organism to detect changes in its external environment and to respond to those changes
62
What is the function of the inner splanchnic tube?
> the visceral or splanchnic tube is involved in metabolic functions
> it includes the gut tube (alimentary tract) and its derivatives such as the liver and pancreas
> the splanchnic tube is responsible for processing nutrients brought into its lumen (cavity) from external sources and making the energy and building blocks (amino acids, monosaccharides, fatty acids, etc.) derived from these nutrients available for anabolic and catabolic aspects of metabolism
>>> anabolic reactions are those that result in the synthesis of complex molecules (I.e., proteins) from simple molecules (I.e., amino acids). They are generally endergonic
>>> catabolic reactions break down complex molecules into simple molecules, usually releasing energy that can be used by cells
63
These types of reaction result in the synthesis of complex molecules from simple molecules and are usually endergonic?
> anabolic reactions
64
These types of reactions break down complex molecules into simple molecules, usually releasing energy that can be used by cells?
> catabolic reactions
65
What space separates the somatic tube from the splanchnic tube in chordates?
> coelom
66
Name the three types of animals that can be based on the type of coelom (or lack of coelom).
> acoelomates
>>> lack a body cavity separating the somatic tube from the visceral tube
> psuedocoelomates
>>>possess a cavity, but it is only partly derived from embryonic mesoderm
> eucoelomates
>>> include most animals, including chordates; they possess a body cavity that is completely lined with derivatives from embryonic mesoderm
67
In regards to the coelom, these animals lack a body cavity separating the somatic tube from the visceral tube?
> acoelomates
68
In regards to the coelom, these animals posses a cavity, but it is only partly derived from embryonic mesoderm?
> psuedocoelomates
69
In regards to the coelom, the animals posses a body cavity that is completely lined with derivatives of embryonic mesoderm?
> eucoelomates
70
The coelom of ________ is lined by mesodermal derivatives that are associated with the somatic tube or the splanchnic tube?
> eucoelomates
71
The lining associated with the somatic tube is referred to as what?
> somatic OR Parietal peritoneum (OR pleura OR pericardium)
72
The lining that is intimately associated with the splanchnic tube is referred to as what?
> splanchnic OR visceral peritoneum (Or pleura OR pericardium)
73
Places where these two layers of lining (lining associated with the somatic tube and lining of splanchnic) tissues meet form double layered suspensory structures called what?
> mesenteries
74
All modern vertebrates other than __________ have two pairs of appendages, although they may be highly modified or even secondarily lost (I.e., snakes)
> cyclostomes
75
The appendages toward the cranial end of the body are referred to as?
> pectoral appendages
76
The appendages closer to the caudal end of the body are refereed to as?
> pelvic appendages
77
Pectoral and pelvic appendages have a similar _________ pattern?
> anatomical
78
The appendages of a while, bird, and human may have enormous superficial ___________, but their basic anatomical plan, as we shall see, is _________?
> differences
| > identical
79
Many invertebrates, such as arthropods, have an external skeleton (exoskeleton), but vertebrates are unique in possessing an?
> internal mesodermal skeleton
>>> mesoderm is one of the three embryonic germ layers. It gives rise to many of the internal structures of the vertebrate body, including a skeletal framework
>>> this internal framework may be constructed entirely of cartilage, entirely of bone, but often of a combination of cartilage and bone
>>> the bony portion of the internal skeleton may form directly as bone or, in most cases, is preceded by cartilage, which is then replaced by bone
80
___________ is one of the three embryonic germ layer. It gives rise to internal structures of the vertebrate body, including a skeletal framework.
> mesoderm
81
The internal framework created by mesoderm maybe constructed entirely of _________, but often a combination of _________ and _________?
> cartilage
> cartilage
> bone
82
The bony portion of the internal skeleton created by mesoderm may form directly as bone or, in most cases, is preceded by cartilage, which is then often __________ by bone?
> bone
83
Except for cyclostomes, the vertebrate __________ musculature is divided into a pair of _______ columns (epaxial musculature) that lie ___________ the dorsal ribs and vertebral travers processes, and hypaxial musculature that lies _________ the dorsal ribs and __________ to the ventral ribs (if present)
```
> axial
> dorsal
> above
> below
> lateral
```
84
___________ musculature consists of segmentally arranged blocks of skeletal muscle referred to as myomeres. In fishes, it is primarily responsible for locomotion and is well developed. It becomes more reduced in tetrapods?
> Epaxial
85
_________ musculature includes the layers of skeletal muscle that form the walls of the body cavities as well as the muscles of the fish fins and tetrapods limbs?
> hypaxial
86
Chordates are ________; they have true body cavities lined with _________?
> eucoelomates
| > mesoderm
87
The coelom consists of what two subdivisions in most vertebrates?
> pericardial (contains the heart)
| > pleuroperitoneal (houses the lungs and other viscera)
88
The coelom consists of what three subdivisions in mammals?
> pericardial (contains the heart)
> pleural (paired cavities containing the lungs)
> peritoneal (contains other viscera)
89
What two cavities are separated by a fibrous transverse septum, in fishes, amphibians, and some reptiles?
> the pericardial cavity is separated from the pleuroperitoneal cavities
90
A _______ _______ _________ separates the pericardial cavity from the pleuroperitoneal cavities in other reptiles and birds, and mammals, a muscular __________ partitions off the pleural cavities from the other cavities?
> tendinous
> oblique
> septum
> diaphragm
91
The body cavities are lined with mesodermal linings referred to as what?
> serous membrane
>>> these serous membranes produce a thin watery lubricating fluid
>>> membranes lining the cavities are referred to as parietal layers: parietal pericardium, parietal pleura, and peritoneum
92
These membranes produce a thin, watery lubricating fluid?
> serous membranes
93
Name the parietal layers.
> parietal pericardium
> parietal pleura
> parietal peritoneum
94
The organs within the body cavities are covered by similar serous membranes termed what?
> visceral layers
> membranes covering the organs within the cavities are referred to as visceral layers: visceral pericardium, visceral pleura, and visceral peritoneum
95
Name the visceral layers.
> visceral pericardium
> visceral pleura
> visceral peritoneum
96
What are the mesenteries?
> transition points where the visceral and parietal peritoneum join and form double layers
97
Transition points where the visceral and parietal peritoneum join and from double layers are called what?
> mesenteries
98
This mesentery suspends the gut tube from the roof of the coelom?
> the dorsal mesentery
99
This mesentery connects the gut tube to the ventral floor of the coelom?
> the ventral mesentery
100
What does the dorsal mesentery do?
> suspends the gut tube from the dorsal roof of the the coelom
101
What does the ventral mesentery do?
> connects the gut tube to the ventral floor of the coelom
102
In the cranial part of the peritoneal coelom, the ventral mesentery connecting the liver to floor of the peritoneal cavity forms what ligament?
> falciform ligament (VM-2)
103
What is the part of the ventral mesentery between the liver and the ventral gut tube called?
> lesser omentum (VM-1)
104
Most of the rest of the ventral mesentery is ___________ during embryonic development due to elongation and coiling of the gut tube?
> obliterated
105
Some organs such as the kidneys lie behind the peritoneum and are referred to as what?
> retroperitoneal
106
What is metamerism?
> metamerism refers to segmentation and describes the subdivision of the body into repeating anatomical units on either side of the midline extending from the cranial to the caudal end
>>> metarism is easy to observe in many invertebrates such as earthworms and insects, but is also very evident in vertebrates, although not so evident externally
>>> the Epaxial musculature is divided blocks of repeating skeletal muscle (myomeres) lying on either side of the notochord or vertebral column. This is especially evident in fishes but can also be seen in tetrapods
>>> metamerism is also evident in the anatomy of the vertebral column, nervous system and kidneys
107
This term refers to the origin of the body plan from three germ layers or primordia?
> Triploblasty
108
What are the three embryonic germ layers?
> ectoderm
> endoderm
> mesoderm
109
Summarize ectoderm.
> ectoderm is the outermost germ layer
| > ectoderm gives rise to the outer layer of the integument and to the nervous system
110
Summarize endoderm.
> endoderm is the innermost germ layer
| > endoderm gives rise to the gut tube and derivatives
111
Summarize mesoderm.
> mesoderm is the middle germ layer
| > mesoderm gives rise to connective tissues, cartilages, bone, muscle, and other related structures and tissues
112
This germ layer gives rise to the outer layer of the integument and to the nervous system?
> ectoderm
113
The germ layer gives rise to the gut tube and its derivatives?
> endoderm
114
This germ layer gives rise to connective tissue, cartilage, bone, muscle, and other related structures and tissues?
> mesoderm
115
Summarize dueterostomy.
> not unique to chordates
> refers to the origin of the oral opening in relation to the anal opening during embryonic development
> in deuterosomes, the original embryonic opening-the blasts pore- becomes the anus, and the mouth develops as a secondary opening
116
This refers to the origin of the oral opening in relation to the anal opening during embryonic development?
> Deuterostomy
117
Summarize cephalization.
> not unique to chordates
| > refers to the development of a definite head (cranial end) characterized by an accumulation of sense organs
118
This refers to the development of a definite head (cranial end) characterized by an accumulation of sense organs?
> cephalization
119
The vertebrate body is divided into what three regions?
> head
>>> head with a concentration of sense organs is generally the first part of the vertebrate body to enter a new milieu
> trunk
>>> the trunk contains most of the viscera and serves as the central support for the appendages
> tail
>>> the tail begins at the caudal opening of the digestive tube (the anus) and is the main organ of locomotion in many fishes, salamanders, and tadpoles. Some vertebrates lose the tail the adult form (frogs, primates, and birds)
