Comparative Anatomy Exam #1

Front 1

Anatomy

Back 1

Branch of morphology that deals with the structure of organisms as revealed by dissection.

Front 2

Morphology

Back 2

the study of the visible form of organisms; the developmental and evolutionary history of these structures.

Front 3

What is the goal of Comparative Anatomy?

Back 3

to present an ontogenetic (individual development) and phylogenetic (species development) morphological structures, their functions, and the animals of which they are a part.

Front 4

Earliest anatomical writings

Back 4

date: 3000 B.C.
Egyptian embalming guides

Front 5

Galen

Back 5

Greek physician in Rome
date: 165-200 A.D.
-authority on anatomy and morphology for over 1000 years.
-compiled everything in Greek and did his own dissections, had over 100 works in anatomy.

Front 6

15th Century: The Renaissance

daVinci

Back 6

made many anatomical drawings and observations.

Front 7

15th Century: The Renaissance

Vesalius

Back 7

date:1533
-Med Student at Univ. of Paris, but quit because of inconsistencies.
-Profs merely pointed at dissections while reading from Galen's work.
-went to Univ. of Padua, earned his degress, and taught.

Front 8

15th Century: The Renaissance

Vesalius publication

Back 8

date: 1543
De humani corporis fabrica (on the structure of the human body)

Front 9

15th Century: The Renaissance

Pierre Belon du Mans

Back 9

date: 1555
-published a comparison of a bird and a human skeleton
-this work noted equivalence between parts of different animals

Front 10

Principles of homology

Original Concept

Back 10

Structures in two different animasl that develop in the same way for the same type of embryonic precursor really are the same.

Cataloguing homologous structures was the main thrust of anatomical research for the next 300 years.

Front 11

Principles of homology

Original Concept Downfalls

Back 11

1) there was no understanding of reasons for homologous structures.
2) no relationship was seen between the occurence of homologous structures in different animals and patterns of relatedness between those animals

Front 12

Charles Darwin

Back 12

date: 1859
Publication: On the origin of species by means of natural selection

This book set forth the evolutionary principles necessary to address questions on the meaning of homology.

Stressed the importance of evolutionary interpretation in understanding amassed anatomical data.

Front 13

Redefined homology

Back 13

those equivalent structures between different organisms derived through inheritance from a common ancestor.

-the study of anatomy evolved into the study of evolutionary morphology.

Front 14

Evolution

Back 14

change

Front 15

Organic Evolution

Back 15

change in the genetic composition of a population from generation to generation

Front 16

Genotype

Back 16

raw material; genetic, heritable information.

Front 17

Phenotype

Back 17

observable properies of an individual, such appearance or morphology

-most studies of evolutionary relationships have been based on this.

Front 18

Natural Selection

Back 18

direction for change; the sum of all environmental factors that determine the relative success of different genotype.

Front 19

Adaptation

Back 19

-Criterion for success
-hereditary adjustment of a species of organism to its environment
-any developmental, behavioral, anatomical, or physiological characteristiv that increases chances of surviving and producing descendants

Front 20

Things to Keep in Mind during Comparative

Back 20

- natural selection is opportunistic
- organisms can't plan ahead
- what may be a beneficial adaptation now could become detrimental in a changing environment

Front 21

How are new species formed?

Back 21

as populations genetically diverge to the point that individuals in each population can no longer successfully interbreed

Front 22

What happens to the ancestral population as divergent evolution occurs?

Back 22

it doesn't remain static it continues to evolve

Front 23

phylogeny

Back 23

relationships of groups of organisms as reflected by their evolutionary history.
-most are reconstructed from similarities and differences in morphological data.

Front 24

homology

Back 24

structures evolved from a common ancestral origin, even though the function may not be the same.

ex. seal flipper, bat wing, horse forelimb-very modified but all from the same embryological and ancestral origin

Front 25

Homoplasy

Back 25

structural similarities not necessarily due to inheritance from a common ancestor

Front 26

Parallelism (parellel evolution)

Back 26

separate evolution of similar characters in lineages that are not of common ancestry

ex. African and American porcupine quills -related rodents, but their lineages independantly evolved quills.
ex. forearm modification in whales and seals - both evolved from a primitive terrestrial carnivore

Front 27

Convergence (convergent evolution)

Back 27

separate evolution of similar characters in lineages that are not of common ancestry.
-the similarity results form adaptation to environments that have very similar selective forces

ex. wings in birds and bats; gliding membranes in flying squirrels and flying lemurs.

Front 28

Analogy

Back 28

structures that serve the same function but are not evolutionarily derived from a common ancestor.

ex. butterfly wings and bat wings

Front 29

Evolutionary Concepts and Classification

Back 29

grouping and naming of animals and plants is as old as mankind.

Front 30

Evolutionary Concepts and Classification

Aristotle

Back 30

Father of Biological Classification
-had typological philosophy: variation is actually distortion or imperfection from the perfect essence.

Front 31

Evolutionary Concepts and Classification

Linne (Linnaeus)

Back 31

date:1758
Publication: 10th ed. of Systemae Naturae
-Father of Taxonomy
-Established rigid heirarchial classification
-Consistently applied binomial nomenclature

Front 32

Darwin

Back 32

there exists a natural classification of organisms that reflects their descent from a common ancestor.
Ranking of taxa is dependent on the degree of modification from the ancestor.

Front 33

Comparative Morphologists and Embryologists

Back 33

First to use their "tools" to test hypotheses of evolutionary relationships and to reconstruct phylogenetic histories

Front 34

Taxonomy

Back 34

study and practive of classifying organisms into related groups

Front 35

Systematics

Back 35

study of kinds and diversity of organisms and the relationships among them

Front 36

Phylogenetics

Back 36

study of relationships of gourp based on their evolutionary history

Front 37

Transverse

Back 37

a dorsal to ventral plane across the body, cuts the organism into anterior (cranial or rostral)and posterior (caudal) halves

Front 38

Frontal

Back 38

anterior to posterior plane laterally oriented, cuts the organism into dorsal and ventral halves

Front 39

Sagittal

Back 39

anterior to posterior plane dorsoventrally oriented, cuts the organism into left and right halves.

Front 40

Phylum Chordata

Back 40

--Subphylum Cephalochordata (head chord)
--Subphylum Urochordata (Tail chord) - also called Tunicata
--Subphylum Hemichordata (half chords) - considered by some to be a Phylum

*these three are called protochordates (early chordates)

Front 41

Phylum Chordata

Back 41

Subphylum Vertebrata (the backboned animals)

Front 42

Phylum Chordata General Characteristics

Back 42

1) Bilateral symmetry
2)regional differentiation (head, trunk, tail)

Front 43

Phylum Chordata Defining Characteristics 1 & 2

Back 43

1)Notochord -single support rod from midbrain to tail, may or may not persist throughout lifespan.

2)pharyngeal gill slits - opening from gut to outside of body wall, may or may not persist throughout lifespan.

Front 44

Phylum Chordata Defining Characteristics 3 & 4

Back 44

3)hollow dorsal nerve chord - single, fluid-filled tube, enlarged in cephalic region to form brain.

4)post anal tail - muscular and skeletal extension beyond anus; some question its validity as a defining character.

Front 45

Phylum Chordata Satellite Characteristics 1 & 2

Back 45

1)Coelom - (tube within a tube) space between body wall and gut where organs live.

2)digestive system - a complete tube with opening at both ends and specialized regions and outgrowths.

Front 46

Phylum Chordata Satellite Characteristic 3

Back 46

3)Excretory System - elimination of water, electrolyte balance
-primitive forms have nephridia only
-advanced forms have tubules, ducts, bladder

Front 47

Phylum Chordata Satellite Characteristic 4

Back 47

4)Reproductive System - discrete sexes (male and female)
-embryonic gonadal tissues present for both sexes, genetic composition determines which tissues develop to maturity

Front 48

Phylum Chordata Satellite Characteristics 5 & 6

Back 48

5)Closed Circulatory System with pump (heart)

6)true endoskeleton - formed from cartilage which may (most vertebrates) or may not (sharks, agnathans) be replaced with bone.

Front 49

Phylum Chordata Satellite Characteristics 7 & 8

Back 49

7)skin - protections, respiration, specialized structures
-vertebrates have 2 layers (epidermis and dermis)

8)paired appendages - pelvic and pectoral limbs

Front 50

Phylum Chordata Satellite Characteristic 9

Back 50

9)segmentation - limited to musculature, skeleton, and some nervous system components
-metamerism - serial repetition of parts along the body length

Front 51

Cephalochordata

Back 51

ex. Amphioxus
-shallow, salt water burrowers, small
-notochord extends into the head region
-pharynx highly modified for feeding

Front 52

Urochordata (Tunicata)

Back 52

ex. tunicates, sea squirts
-adults are sessile filter feeders with littel resemblance to vertebrates but larval forms have typical chordate characteristics

Front 53

Hemichordata

Back 53

ex. acorm worms, proboscis worms
-notochord (called stomochord in this case) is in the proboscis
-burrowers
-hemichordate larvae are very similar to Echinoderm (starfish and relatives) larvae

Front 54

Which of the protochordates represents a direct ancestor of the vertebrates?

Back 54

none of them, but a common ancestor may have given rise to each group, therefore they are remnants of the main line of vertebrates.

Front 55

Metazoa

Back 55

a subkingdom name applied to all multicellular animals excepts sponges

Front 56

Cnidarians

Back 56

ex. corals, jellyfishes, sea anemones
-lower metazoans considered to be little changed form the common ancestor that gave rise to all metazoans due to absence of middle body layer (mesoderm)
-the primitve condition is thought to be skin (ectoderm) and gut (endoderm)

Front 57

Almost all Metazoans about the Cnidarian level have:

Back 57

-3 body layers (ecto-, meso-, endo- derm): the mesoderm forms muscle, circulatory, skeletal, genital tissues
-true coelom
-mouth and anus: digestive tube opens and both ends

Front 58

Which of the Metazoans groups might have provided the ancestor to the Chordates?

Back 58

Arachnids (spiders and mites)
Annelids (segmented worms)
Echinoderms (starfish and allies)

Front 59

Annelid and/or Arachnid ancestry of Chordates
Reasons FOR

Back 59

1)bilaterl symmetry
2)segmentation
3)enlarged brain

Front 60

Annelid and/or Arachnid ancestry of Chordates
Reasons AGAINST

Back 60

1)segmentation is complete (in chordates it is limited to mesodermal derivatives)
2)nerve chord is ventral
3)mesoderm formation is Schizocoelous (arises as solid masses of cells budding off near the posterior end of body near the blastopore)

Front 61

Echinoderm Ancestry of Chordates
Reasons FOR

Back 61

1)entercoelous mesoderm formation (arises by a sac-like outfolding from the gut layer.
2)blastopore becomes the anus (it becomes the mouth in other metazoans)
3)dipleurula larvae - characterized by a band of cilia around the mouth.

Front 62

Vertebrate Characteristics

Back 62

1)all three primary chordate characteristics
2)Two pairs of appendages
3)protective skin
4)highly developed brain enclosed in a cranium and a nerve cord enclosed by vertebrae
5)endoskeleton
6)well developed sense organs
7)closed circulatory system:ventral heart, dorsal major artery
8)digestive system with both mouth and anus

Front 63

Vertebrate Taxonomy

Back 63

Phylum: Chordata
Subphylum: Vertebrata
Superclass(1): Pisces (fish-like forms)
Superclass: Tetrapoda (terrestrial 4-legged forms)

Front 64

Vertebrate Taxonomy
Superclass Pisces

Back 64

Class:Agnatha
Class:Chondrichthyes (Elasmobranchiomorphi)
Class:Osteichthyes
Class:Placodermi (extinct)

Front 65

Vertebrate Taxonomy
Superclass Tetrapoda

Back 65

Class: Amphibia
Class: Reptilia
Class: Aves
Class: Mammalia

Front 66

Superclass Pisces
Class Agnatha
General Characteristics

Back 66

Jawless vertebrates (suckers)
-no paired appendages
-cartilage skeleton
-single nostril on top of head (monorhinous)

Front 67

Superclass Pisces
Class Agnatha
Example

Back 67

Ostracoderms: oldest known fossil vertebrates, covered externally by body plates

Front 68

Superclass Pisces
Class Agnatha
Subclasses

Back 68

Subclass Petromyzontia (Cyclostomata): extant agnathans, lampreys (larval forms called ammocoetes)

Subclass Myxinoidea: hagfishes

Front 69

Superclass Pisces
Class Placodermi
General Characteristics

Back 69

-first jawed vertebrates
-known only from fossils, some investigators consider them a subclass of Chondrichthyes
-heavy bony armour
-paired fins developing

Front 70

Superclass Pisces
Class Chondrichthyes
(Elasmobranchiomorphi)
General Characteristics

Back 70

Cartilagenous jawed fishes

Front 71

Superclass Pisces
Class Chondrichthyes
(Elasmobranchiomorphi)
Subclass Elasmobranchii
General Characteristics

Back 71

ex. Sharks, Skates, Rays
-upper jaw not attached to braincase
-teeth from placoid scales
-internal fertilization with claspers
-most ovoviviparous (egg develops in female, live birth)

Front 72

Superclass Pisces
Class Chondrichthyes
(Elasmobranchiomorphi)
Orders

Back 72

Order Squaliformes - true sharks, have heterocercal tail

Order Rajiiformes - skates and rays

Front 73

Superclass Pisces
Class Chondrichthyes
(Elasmobranchiomorphi)
Subclass Holocephali
Order

Back 73

Order Chimaeriformes - ratfishes and chimaeras

Front 74

Superclass Pisces
Class Acanthodii
General Characteristics and Facts

Back 74

ex. spiny sharks (extinct)
-3 to 5 inches long
-some investigators group these with Osteichthyes, some with Placodermi, and some say they stand apart (including Hildebrand)

Front 75

Superclass Pisces
Class Osteichthyes
General Characteristics

Back 75

-bony fishes
-have jaws
-paired appendages
-dermal scales

Front 76

Superclass Pisces
Class Osteichthyes
Subclass Sarcopterygii
General Characteristics

Back 76

lobe finned fishes

Front 77

Superclass Pisces
Class Osteichthyes
Subclass Sarcopterygii
Order Crossopterygii
Suborders

Back 77

Suborder Rhipidista - gave rise to amphibians

Suborder Coelacanthiformes - genus Latimeria extant

Front 78

Superclass Pisces
Class Osteichthyes
Subclass Sarcopterygii
Order Dipnoi
General Characteristics

Back 78

lung fishes - have lungs instead of air bladders and lobe fins with strong skeletal elements

Front 79

Superclass Pisces
Class Osteichthyes
Subclass Actinopterygii
General Characteristics

Back 79

ray-finned fishes

Front 80

Superclass Pisces
Class Osteichthyes
Subclass Actinopterygii
Infraclass Chondrostei
General Characteristics

Back 80

ex. sturgeons, paddlefishes
-Polypterus: a genus that some authors believe belongs in an order within the Actinopterygii, but others believe it is a separate subclass (Brachiopterygii)
-enigmatic because it shows a blend of Sarcopterygian and Actinopterygii characters.

Front 81

Superclass Pisces
Class Osteichthyes
Subclass Actinopterygii
Infraclass Neopterygii
General Characteristics

Back 81

gars and bowfin, modern ray-finned fishes

Front 82

Superclass Pisces
Class Osteichthyes
Subclass Actinopterygii
Infraclass Neopterygii
Superorder Teleostei
General Characteristics

Back 82

modern ray-finned fishes

Front 83

Superclass Tetrapoda
General Characteristics

Back 83

-amphibians and reptiles are ectothermal
-birds and mammals are endothermic so they can exploit a wider range of habitat

Front 84

Superclass Tetrapoda
Class Amphibia

Back 84

-earliest adaptations for life on land were probably adaptations to get across land to more water.
-begin a shift from gills to lungs, swimming to walk.
-lungs and skin used for respiration
-heart with 2 atria and 1 ventricle
-some develop to live on land but most return to water to reproduce (eggs laid in water or most habitat)
-young usually begin as gill breathers then may shift to lungs

Front 85

Superclass Tetrapoda
Class Amphibia
Labyrinthodonts

Back 85

-had teeth with infolded enamel
-were the first land vertebrates

Front 86

Superclass Tetrapoda
Class Amphibia
Subclasses

Back 86

Subclass Anthracosauria - gave rise to rest of vertebrates

Subclass Temnospondyli - diverse group, semi-aquatic

Subclass Ichthyostegalia - earliest amphibians (first tetrapods)

Subclass Lissamphibia - modern amphibians

Front 87

Superclass Tetrapoda
Class Amphibia
Subclass Lissamphibia
Order Anura (Salientia)

Back 87

ex. frogs and toads
-lose tails as adults
-have vocal cords
-caudal vertebrae fused to form the urostyle

Front 88

Superclass Tetrapoda
Class Amphibia
Subclass Lissamphibia
Order Urodela (Caudata)

Back 88

ex. salamanders
-keep tail throughout life
-no vocal cords

Front 89

Superclass Tetrapoda
Class Amphibia
Subclass Lissamphibia
Order Apoda (Gymnophiona)

Back 89

ex. caecilians

Front 90

Superclass Tetrapoda
Class Reptilia
General Characteristics

Back 90

-fully terrestrial, developed amniote (cleidoic) egg in which the embryo has extraembryonic membrane and a relatively impermeable shell

Front 91

Superclass Tetrapoda
Class Reptilia
Membrane Names

Back 91

yolk - involved in nutrition

allantois - waste removal

amnion - protection, moisture

chorion - respiration

Front 92

What are the subclass names based on in Class Reptilia?

Back 92

number of openings in the skull

Front 93

Superclass Tetrapoda
Class Reptilia
Subclass Anapsida
General Characteristics

Back 93

-"no hole"
-gave rise to other reptiles

Front 94

Superclass Tetrapoda
Class Reptilia
Subclass Anapsida
Order

Back 94

Order Cotylosauria - stem reptiles, very similar to amphibians

Front 95

Superclass Tetrapoda
Class Reptilia
Subclass Testudinata
(Testudines or Chelonia)
General Characteristics

Back 95

ex. turtles
-once an order within Anapsida
-ribs modified to make carapace
-no teeth, just a sharp, horny beak
-girdles inside ribs

Front 96

Superclass Tetrapoda
Class Reptilia
Subclass Diapsida
General Characteristics

Back 96

- "2 holes"

Front 97

Superclass Tetrapoda
Class Reptilia
Subclass Diapsida
Infraclass Lepidosauria
Order Rhyncocephalia
General Characteristics

Back 97

-genus Sphenodon (tuatara)
-found in New Zealand
-teeth fused to jaw
-abdominal ribs

Front 98

Superclass Tetrapoda
Class Reptilia
Subclass Diapsida
Infraclass Lepidosauria
Order Squamata
Suborders

Back 98

(following are the extant Lepidosaurs)
-Suborder Sauria (Lacertilia) - lizards
-Suborder Serpentes (Ophidia) - snakes
-Suborder Amphisbaenia - amphisbaenians

Front 99

Superclass Tetrapoda
Class Reptilia
Subclass Diapsida
Infraclass Archosauria
General Characteristics

Back 99

-Ruling reptiles
-these are advanced diapsids

Front 100

Superclass Tetrapoda
Class Reptilia
Subclass Diapsida
Infraclass Archosauria
Orders

Back 100

-Order Thecodontia - ancestral archosaurs
-Order Crocodilia - crocodiles, alligators (extant)
-Order Pterosauria - flying reptiles
-Order Saurischia - reptile-like dinosaurs, gave rise to birds
-Order Ornithischia - bird-like dinosaurs, bird characteristics but went extinct and are not bird ancestors

Front 101

Superclass Tetrapoda
Class Reptilia
Subclass Diapsida
Controversial Infraclasses

Back 101

(Once considered Subclass Euryapsida -"one hole", based on a misinterpretation of skulls)
-Infraclass Ichthyosauria - Ichthyosaurs (fish shaped reptiles)
-Infraclass Sauropterygia - Plesiosaurs

Front 102

Superclass Tetrapoda
Class Reptilia
Subclass Synapsida
General Characteristics

Back 102

one, laterally places temporal fenestra

Front 103

Superclass Tetrapoda
Class Reptilia
Subclass Synapsida
Orders

Back 103

-Order Pelycosauria - primitive synapsids
-Order Therapsida - moderm synapsids, gave rise to mammals

Front 104

Superclass Tetrapoda
Class Aves
Subclass Arachaeornithes

Back 104

Genus Archaeopteryx ("ancient wing")
-Seven specimens known
-First bird in the fossil record

Front 105

Superclass Tetrapoda
Class Aves
Subclass Enantiornithes

Back 105

advanaced over Archaeopterx in modern bird features

Front 106

Superclass Tetrapoda
Class Aves
Subclass Neornithes
Infraclasses

Back 106

-Infraclass Odontognathae ("tooth mouth") - toothed birds from the Cretaceous
-Infraclass Paleognathae - ratite birds (flightless forms like ostrich, emu)
-Infraclass Neognathae - most of the surviving birds, about 27 extant orders

Front 107

Superclass Tetrapoda
Class Mammalia
Subclass Prototheria

Back 107

"First mammal"
-Order Monotremata - extant, duckbill platypus and spiny anteater

Front 108

Superclass Tetrapoda
Class Mammalia
Subclass Allotheria

Back 108

-Order Multituberculata - rodent-like mesozoic mammals

Front 109

Superclass Tetrapoda
Class Mammalia
Subclass Theria

Back 109

"theria" means mammal

Front 110

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Trituberculata

Back 110

-extinct
-3 tubercles on teeth

Front 111

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Metatheria

Back 111

-marsupials (extant)
-some group these into one order (Marsupialia)
-others may subdivide into 4 orders

Front 112

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Beginning of Cenozoic

Back 112

there was a great radiation from the insectivorous ancestors

Front 113

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria

Back 113

Placental mammals

Front 114

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Insectivora

Back 114

shrews and moles

Front 115

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Edentata

Back 115

armadillos and sloths

Front 116

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Pholidota

Back 116

pangolins (scaly anteaters)

Front 117

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Dermoptera

Back 117

colugos or "flying lemurs"

Front 118

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Chiroptera

Back 118

bats

-suborder Megachiroptera - flying foxes
-suborder Microchiroptera - most bats (smaller)

Front 119

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Primates

Back 119

monkeys, apes, baboons, humans, etc.

Front 120

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Lagomorpha

Back 120

rabbits and hares

Front 121

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Rodentia

Back 121

rats, mice, squirrels, beaver, etc.

Front 122

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Carnivora

Back 122

carnivores

Suborder Fissipedia - terrestrial carnivores
Suborder Pinnepedia - seals, sea lions, walrus; some consider the Pinnipedia to be an order

Front 123

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Cetacea

Back 123

whales, porpoises

Suborder Mysticeti - baleen whales
Suborder Odontocet - toothed whales

Front 124

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Tublidentata

Back 124

aardvark

Front 125

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Proboscidea

Back 125

elephants

Front 126

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Hyracoidea

Back 126

hyraxes or conies

Front 127

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Sirenia

Back 127

manatees, sea cows, dugongs

Front 128

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Perissodactyla

Back 128

odd-toed ungulates (horses, asses, zebras, rhinoceros)

Front 129

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Order Artiodactyla

Back 129

even-toed ungulates (cows deer, antelope, pronghorn, pigs, etc.)

Front 130

Superclass Tetrapoda
Class Mammalia
Subclass Theria
Infraclass Eutheria
Other Orders

Back 130

8 other are extinct

Front 131

Tissue

Back 131

Composed of many cells, similar in structure and function, bound together by intercellular matrix material

Front 132

Organ

Back 132

Composed of tissues (which are not necessarily similar) grouped together in a structural/functional unit

Front 133

Organ System

Back 133

A group of interacting organs that cooperate as a functional complex

Front 134

Animal Tissues are divided into how many major types

Back 134

4

Front 135

Epithelium

Back 135

-Covering or lining of all free body surfaces
-Cells packed tightly together, little intercellular space
-One surface is exposed to the open, one is fluid
-Free ends bear structures like hairs, microvilli, cilia, mucous secretions, etc.

Front 136

Layers of Epithelium
Simple

Back 136

a single layer of cells

Front 137

Layers of Epithelium
Stratified

Back 137

more than one layer of cells

Front 138

Layers of Epiithelium
Psuedostratified

Back 138

all cells are in contact with the basement membrane (it is a single layer) but the nuclei are pushed around and it looks stratified

Front 139

Types of Cells
Squamous

Back 139

cells are broader than thick; thin, flat sheets are formed

Front 140

Type of Cells
Cuboidal

Back 140

cells are as broad as they are thick, cube shaped in cross section

Front 141

Type of Cells
Columnar

Back 141

cells are taller rather than wide, look like rectangles set on end in cross section

-pseudostratified epithelium is made of columnar cells

Front 142

Glands

Back 142

epithelium is often modified as gland cells, of which there are 3 classes based on the fate of the cell after secretion

Front 143

Types of Glands
Merocrine Gland

Back 143

no harm to the cell
ex. sweat and wax glands

Front 144

Types of Glands
Apocrine Gland

Back 144

cell is damaged but recovers
ex. scent glands

Front 145

Types of Glands
Holocrine Gland

Back 145

cell is destroyed
ex. sebaceous (oil) glands in mammalian skin

Front 146

Types of Glands
Discrete Gland

Back 146

(many cells work together in a group, rather than singly)

These are classified by how the product is discharged into the body

Front 147

Types of Glands
Exocrine Glands

Back 147

discharged by ducts
ex. salivary glands

Front 148

Types of Glands
Endocrine Glands

Back 148

discharge into the blood stream
ex. pituitary gland

Front 149

Muscle

Back 149

-great capacity for contraction, responsible for movement

-individual cells are elongate and bound together in bundles or sheets by connective tissue

Front 150

Types of Muscle
Skeletal

Back 150

-Striated
-named for appearance of striations across the cell
-multinucleated cells
-responsible for voluntary movement

Front 151

Types of Muscle
Smooth

Back 151

-responsible for involuntary movement
-found in internal organs
-one nucleus per cell

Front 152

Types of Muscle
Cardiac

Back 152

-heart muscle
-branching pattern
-striated
-distinguished by intercalating discs, where cells touch one another

Front 153

Nerve Tissue

Back 153

-highly specialized for response to stimuli
-transmits impulses very rapidly
-extremely elongate, fibers bound together by connective tissue to form a nerve

Front 154

Connective Tissue

Back 154

-arises from embryonic mesenchyme
-cells are always embedded in an intercellular matrix which may be solid (bone), semi-solid (cartilage), or liquid (blood)

Front 155

Types of Connective Tissue
Blood

Back 155

supported in the fluid (lymph)

Front 156

Types of Connective Tissue
Connective Tissue Proper

Back 156

always contains collagen, elastin, and reticular fibers

Front 157

Types of Connective Tissue
Cartilage

Back 157

-rubbery
-few cells, but lots of matrix

Front 158

Types of Connective Tissue
Bone

Back 158

-hard, rigid
-matrix contains calcium carbonate and calcium phosphate

Front 159

Dioecious

Back 159

male sperm and female ova (2 individuals required)

Front 160

Monoecious

Back 160

hermaphroditic forms, male and female in the same individual, self fertilization
ex. some fishes

Front 161

Parthenogenesis

Back 161

only females, no fertilization required

Front 162

Fertilization

Back 162

fusion of sperm and egg nuclei reconstituting the diploid chromosome number produces a zygote

Front 163

Types of Fertilization
Internal

Back 163

takes place within the female's body

Front 164

Types of Fertilization
Spermatophore

Back 164

salamanders fertilize internally but do not have copulatory organs for sperm placement, thus male deposits this "sperm packet" and the female picks it up

Front 165

Types of Fertilization
External

Back 165

sperm and ova are released into the water in large numbers, such as in spawning

Front 166

viviparous

Back 166

-egg is retained in female's body during development

-live birth

-developing embryo depends on female for protection, nourishment, waste removal, oxygen

Front 167

ovoviviparous

Back 167

egg is retained in female's body during development but very little contact exists between female and developing embryo (depends on yolk in the egg)

Front 168

oviparous

Back 168

-egg is deposited in the environment, no contact between female and developing embryo

-covered with a "shell" or gelatinous guarding coat

Front 169

What are egg types based on?

Back 169

the amount and distribution of yolk

Front 170

yolk

Back 170

the nutritive complex of proteins, phospholipids, and fats

Front 171

Types of Eggs
Based on Amount of Yolk
Microlecithal

Back 171

very small amount of yolk ex.amphioxus and mammals

Front 172

Types of Eggs
Based on Amount of Yolk
Mesolecithal

Back 172

moderate amount of yolk
ex. amphibians, lungfishes, lampreys, lower Actinopterygians

Front 173

Types of Eggs
Based on Amount of Yolk
Macrolecithal

Back 173

yolk makes up most of the volume of the egg
ex. reptiles, birds, some sharks

Front 174

Types of Eggs
Based on Distribution of Yolk
Isolecithal

Back 174

-yolk is evenly distributed throughout the cell

-found in microlecithal eggs

Front 175

Types of Eggs
Based on Distribution of Yolk
Telolecithal

Back 175

-yolk is concentrated at one "pole"

-found in mesolecithal and macrolecithal eggs

-animal pole: end with most of cytoplasm

-vegetal pole: end with most of yolk

Front 176

What does distribution of yolk determine or affect?

Back 176

it determines cleavage patterns, which affect all of later development

Front 177

cleavage

Back 177

process forming the blastula; a period of rapid, synchronized cell division greatly increasing the number of cells in the egg

Front 178

Types of Cleavage
Holoblastic Equal

Back 178

-little yolk (ex. amphioxus)

-divisions leading to the blastula stage produce a hollow ball.

Front 179

Types of Cleavage
Holoblastic Unequal

Back 179

-moderate yolk (ex. primitive fishes, amphibians)

-the blastocoel is off-center and cells surrounding it are different in appearance

Front 180

Types of Cleavage
Meroblastic

Back 180

--much yolk (ex. reptiles, fishes birds)
--cleavage is partial because it does not pentrate the yolk mass
--active cytoplasm is at the animal pole, yolk at the vegetal pole
--yolk takes up much of the space in the cell mass

Front 181

Types of Cleavage
Mammalian Holoblastic

Back 181

-little yolk, cleavage is total and equal because there is little yolk

Front 182

blastocoel

Back 182

the inside cavity of the blastula

Front 183

blastoderm

Back 183

the region of cell division in the blastula (animal pole)

Front 184

trophoblast

Back 184

the outer wall of the mammalian blastocyst (the blastula of mammals, characterized by a large blastocoel)

Front 185

zygote

Back 185

a fertilized cell which undergoes cleavage forming a blastula with its blastocoel.

Front 186

How many cells does a blastula typically have

Back 186

-256 cells
-8 cell divisions

Front 187

gastrulation

Back 187

the blastula undergoes this formation of early embryo

Front 188

blastopore

Back 188

opening to the gastrocoel

Front 189

gastrocoel

Back 189

the cavity of the gastrula

Front 190

Archenteron

Back 190

embryonic digestive tube

Front 191

Resulting gastula posesses:

Back 191

the primary germ layers (2 or 3, depends on the species)

-ectoderm (outer)
-mesoderm (middle)
-endoderm (inner)

Front 192

invagination

Back 192

-possible with there is little yolk
-the vegetal pole turns inward toward the animal pole and eventually obliterates the blastocoel
-creates two layers, ectoderm and endoderm
-new cavity (gastrocoel)
-small opening (blastopore)
-mesoderm forms the gut

Front 193

involution

Back 193

-required when yolk is in the way
-cells roll inward at the site of the future blastopore and extend into the blastocoel as a second layer of cells

Front 194

Endodermal Differentiation

Back 194

endoderm becomes epithelial cells of intesting and epithelial outgrowths of the intestine
ex. gill pouches, gills, larynx, trachea, lungs, tonsils, thyroid gland, thymus gland, liver, gall bladder, bile duct, pancreas, urinary bladder

Front 195

Ectodermal Differentiation
Neural Ectoderm

Back 195

-neural tube
ex. brain, spinal cord, nerves, retina of the eye, some pigemtn cells, some portions of the cranial skeleton

Front 196

Ectodermal Differentiation
Non-Neural Ectoderm

Back 196

-external layer of skin (epidermis) and its derivatives (hair, etc.)
ex. lining of the nasal cavities , mouth, and anus; glands of the nasal cavities, mouth, anus, and skin; enamel of teeth; lens of eye; sensory portion of all sense organs

Front 197

Mesodermal Differentiation
Epimere

Back 197

segmented dorsal division of embryonic lateral mesoderm

Front 198

Mesodermal Differentiation
Epimere
Schlerotome

Back 198

forms sheath around notochord, becomes vertebrae

Front 199

Mesodermal Differentiation
Epimere
Dermatome

Back 199

forms dermis of skin

Front 200

Mesodermal Differentiation
Epimere
Myotomes

Back 200

forms skeletal muscle

Front 201

Mesodermal Differentiation
Mesomere

Back 201

small middle division of embryonic lateral mesoderm

Front 202

Mesodermal Differentiation
Mesomere
Nephric Ridge

Back 202

produces kidneys and reproductive organs

Front 203

Mesodermal Differentiation
Hypomere

Back 203

unsegmented vental divsion of the embryonic lateral mesoderm

Front 204

Mesodermal Differentiation
Hypomere
Somatic Mesoderm (Somatopleure)

Back 204

contribues to somatic muscles

Front 205

Mesodermal Differentiation
Hypomere
Splanchnic Mesoderm (Splanchnopleure)

Back 205

surrounds disgestive tract, large blood vessels, forms disgestive tract muscles, contibutes to organs and derivatives of digestive tract, forms much of heart

Front 206

Mesenchyme

Back 206

-specialized, primitive connective tissue

-originates from all 3 germ layers and gives rise to connective tissue

Front 207

amniote egg

Back 207

-found in reptiles birds and mammals

-4 membranes

Front 208

Amniote Egg Membranes
Yolk Sac

Back 208

contains yolk, provides nourishment

Front 209

Amniote Egg Membranes
Allantois

Back 209

provides place for waste removal, respiratory gas diffusion, embryonic urinary bladder

Front 210

Amniote Egg Membranes
Chorion

Back 210

protection, respiration, outermost membrane

Front 211

Amniote Egg Membranes
Amnion

Back 211

contains water (breaks at birth), protection

Front 212

Placenta

Back 212

nutritive arrangement in viviparous animals, consists of folds of one of the extraembryonic membranes interdigitation or lying in contact with maternal, uterine tissue

Front 213

Yolk Sac Placenta

Back 213

found in vivparous sharks, reptiles, and marsupial mammals

Front 214

Chorioallantoic Placenta

Back 214

-in eutherian mammals

-has highly vascularized finger-like projections from the chorioallantoic membrane.

Front 215

Trophoblast

Back 215

fetal contribution to placenta, grows into the endometrial lining of maternal uterus

Front 216

Inner Cell Mass (1)

Back 216

-forms the embryo "proper"

-will differentiate into the 1)amnion, 2)blastoderm, 3)yolk sac (empty)

-all 3 are composed of ectoderm/endoderm

Front 217

Inner Cell Mass (2)

Back 217

-mesoderm grows down over the yolk sac and amnion and finally outward to line the inside of the trophoblast - converts to chorion

-allantois - from floor of archenteron, fuses to chorion

Front 218

Ontogeny

Back 218

individual development from fertilization to death

Front 219

Biogenetic Law

Back 219

individual development repeats the history of a race

"Ontogeny recapitulates phylogeny " - Ernst Haekel

Front 220

Von Baer (1)

Back 220

- general characteristics appear in embryological development before specific ones

-more specific characteristics develop from more general ones

Front 221

Von Baer (2)

Back 221

-animals progressibely diverge more from related froms during development

-early stages of advanced forms resemble those same early stages of primitive forms