Exam I Flashcards

Question

Sarcopterygii have two species left

Answer 1

-lungfish -coelacanth

Answer 2

(direct ancestors of tetrapods) -prob had lungs (evolved as an accessory respiratory structure) -used fins for support and movement -eventually became bottom walking -bony and robust skull -powerful jaws -shifting eyes to top of head to feed above water -skull flattened -skull detached from pectoral girdle (forming true neck)

Answer 3

-eusthenopteron -panderichthys -tiktaalik -acanthostegg -ichthypstegg -tulerpeton

Answer 4

-shallow water predator with flat, elongated snout -large pectoral fins -very fish like (is a fish) -lobbed fin (couldn't support its weight) -lots of fins going out its side -swam fast, was a predator

Answer 5

-predatory fish with flat head -long snout -dorsal eyes, strong, flat humerous -no longer had tail fin bc wasn't propelling itself -fins more elongates -could prob walk in water, not land -had something like an elbow -does not have a neck

Answer 6

-flat head and body -raised dorsal eyes -mobile neck -robust forlimbs and girdle -has elbow -has hand that looks more like paddle -could stick head above water -could not leave water

Answer 7

-similar to tikaalik but with 8 digits on each limb -cant walk on land -powerful swimmer and predator -first guy to have something like a hand -more like a paddle with three bones -don't have a wrist

Answer 8

-7 digits and sturdy -stout limbs -could prob move short distances on land -longer and stronger paddle -some fingers may have actually been fingers -was not fast

Answer 9

-6 digits now -recognizable vert limb -least aquatic and could move well on land -wrist and elbow

Answer 10

acanthostega, ichthyostega, tulerpton all part of paraphyletic group: ichthyostegalia (now fully extinct) (when on land, were top and largest predator)

Answer 11

temnospodyli (lead to all other tetrapods) (large sized, semiaquatic predators resembling crocs) (strong skull, stout limbs, powerful tail, bred in water)

Answer 12

Lissamphibia (owed the land not far from water, evolved true limbs, fingers, toes, claws, shoulders, neck, strong skull) (still laid eggs in water like modern amphibians) (direct ancestors of amphibians) (extinctions chopped these guys down)

Answer 13

-anthracosauria -lepospondyli

Answer 14

-defined by having amniotic egg -laid on land -represents all reptiles, birds, and mammals -results in group called amniotes -key to getting away from water -all reptiles are amniotes, but not all amniotes are reptiles

Answer 15

Sauropsida (birds and dinos are also these) (mammals branched off and did their own thing)

Answer 16

any amniote that is not a modern bird or mammal

Answer 17

early sauropods branched into two groups: -parareptilla -eureptilla

Answer 18

Having a solid skull with no openings

Answer 19

developed two openings in the skull known as diapsid condition (forming the group diapsida)

Answer 20

-lepidosauria -archosauria

Answer 21

-first representative that looked similar to modern tuatara -strong beak-like head -multiple rows of teeth fused to jaw -hard and strong bite -sawing motion with jaw -only the tuatara survives today

Answer 22

-rhychocephalians -squamates -archosaurs

Answer 23

-snakes, lizards, amphibians -most species living reptile group (they are doing great rn)

Answer 24

-socketed teeth -added openings in their snout and jaw (lighten) -complex parental care -diverse group -bad ass -first flying verts (pterosaurs)

Answer 25

Crocodylian Lineage

Answer 26

-defined by compact skull -earliest representatives were small and bipedal -more modern looking crocs came along about 100 million years ago -still around today and are a dominant species

Answer 27

-how turtles are related to everything else is till debatable -they have no openings in their skull, so originally thought to be parareptiles -genetic evidence put them as a sister group to archosaurs -most recent research shows them to be derived from diapsids

Answer 28

Anura, Urodela, Gymnophionia

Answer 29

Temnospondyli and Amniota

Answer 30

Sauropsida

Answer 31

Parareptillia and Eureptilia

Answer 32

Testudines? Nah

Answer 33

Testudines?, Archosauria, Lepidosauria

Answer 34

Crocodylia

Answer 35

Rhynocephalia and Squamata

Answer 36

Cleavage is the division of embryonic cells -zygote divides, but does not increase in size

Answer 37

when zygote start to divide but not increase in size

Answer 38

Formed an 8 cell ball

Answer 39

Forms a hollow ball of cells (the hollow part changes in size based on the amount of yolk needed)

Answer 40

The hollow center of the blastula

Answer 41

Needed to give nutrients to the embryo, this increases or decreases in size depending on how large/developed the embryo will be or how long it is stored for -tadpoles hold yolk in their swimming bodies to give them a head start

Answer 42

-isolecithal -mesolecithal -marcolecithal

Answer 43

Yolk amount is small and evenly distributed, found in placental mammals

Answer 44

Modern amount of yolk, found in most amphibians, young must start feeing before fully developed (amphibians)

Answer 45

Amount of yolk, found in reptiles, birds, and egg laying mammals (lots)

Answer 46

The unfolding of form and structure (transition of undifferentiated cells into differential cells, tissues, organs, and eventually an organism) (amphibians become free living a lot earlier than reptiles, but they undergo metamorphosis)

Answer 47

Free living embryo as opposed to one that fully develops in the egg/parent -allows for them to feed on their own -they have some yolk to give head start -can grow larger and develop at the same time

Answer 48

-mostly aquatic -fish-like characteristics -think skin (2-3 epidermal layers) -highly vascularized -pharyngeal slits and external gills -lidless eyes and large external nares -muscular trunks and long tails with dorsal/ventral fins -lateral line system to detect current flow (start fishy looking and as mature they get their normal look)

Answer 49

-they have anatomy similar to adults -they look like mini adults as kids

Answer 50

-have very different anatomy than adults -they are tadpoles, so they need to undergo metamorphosis (have oral disk for a mouth, external gills replaced by internal gills, spherical body, coiled intestine, tail)

Answer 51

Changes in timing/rate of growth

Answer 52

if you decelerate the development of a trait (more common in amphibians)

Answer 53

if you accelerate the development of a trait (adopted characters are adopted early)

Answer 54

What results in variability in larval development and why some adults keep traits and others grow out of

Answer 55

the transition from an embryo to a juvenile/adult -larval traits are lost -causes major changes in anurans instead os lissamphibians

Answer 56

you can brow big before becoming the adult form -they use their larval stage to go ham and pack on as much food as possible

Answer 57

Thyrozine (TH) -thyroid gland releases the TH and the thyroid homorome receptors (TR) repress development until they are exposed to TH and metamorphosis begins

Answer 58

hatch as little adults and skip metamorphosis (some tiny froglets do this)

Answer 59

-reptiles skip metamorphosis -the embryo develops into a juvenile in the amniotic egg

Answer 60

Pro: protection and lots of yolk -will not dry out on land -come out ready and set (developed) Con: cannot eat -cannot grow larger than the egg -cannot change environmental conditions (stuck in same spot)

Answer 61

Indeterminate= growth does not stop as sexual maturity, continues for life (crocs, snakes, turtles) Determinate= stops at sexual maturity

Answer 62

-aka vertebrate skin -split in two: epidermis (can see, on outside) dermis (cannot see, on inside)

Answer 63

Several layers of cells that are constantly shed and regrown -new cells grow off the stratum germinativum -the outer most cells past the stratum germinativum are dead -these form hard, rigid proteins called keratin

Answer 64

hair, skin, claws, feathers, horns, nails made from dead epidermal cells with a large amount of keratin

Answer 65

Made up of connective tissue consisting of protein fibers, blood vessels, nerves -glands usually epidermal but tend to move into this area because it is bigger -gives skin its strength and elasticity -alive

Answer 66

Stratum spongiosum (spongy layer) Stratum compactum (compact layer)

Answer 67

-cells with specialized pigment producing components -three types: melanophores= brown/black (mammals) xanthophores=yellow/red iridophores=blue -many herps communicate using colors

Answer 68

-moist -thin epidermis with little keratin -thick dermis with many glands, chromatophores, and blood vessels -warts= thickened regions of skin to reduce evaporation -thick dermis used for defense (secretions) and breathing (need to be moist)

Answer 69

-make mucous to keep skin most -more on back than belly bc evaporation -constantly producing a thin layer to keep moist

Answer 70

-produce defenses against skin bacteria/fungal infections -many unhealthy amphibians die from infections

Answer 71

-produce poisons and toxins -tend to be concentrated on the head and shoulders -can be from macroglands you can see on body

Answer 72

-don't have scales, hair, feathers, true nails/claws -have specialized keratinized structures: claw tips spines nuptial pads spades

Answer 73

-unique -have ring (primary annulus) per vertebra and rib -each annulus separates a portion of axial muscle -some species have bony scales in their dermis

Answer 74

-shedding skin -mucus develops under the stratum corneum (mucus lake) -controlled hormonally -dead layer is pealed off with limbs -eaten for nutrients and no prey detection

Answer 75

-the earliest amniotes probably had scale-like structure in their skin made of alpha-keratin -lead to scales on modern reptiles/birds -reptile scales have beta-keratin (brittle and hard)

Answer 76

Inside= stratum germinativum, then alpha keratin, then a mesolayer, then beta keratin, then a oberhautchen layer on outside (dead layer)

Answer 77

All reptiles with limbs have claws

Answer 78

-bony plates made from and found within dermis -reinforces scales beneath -fused with the skeleton -inner layer is compact bone, and the outer layer is spongy

Answer 79

-multicellular glands all over but very small (waterproof with lipids and produce hormones) -major glandular aggregations exist but need to be where no scales are so it can secrete -usually on hind limbs, shoulders, or around genitals

Answer 80

-shedding skin -crocs and turtles have cells shed individually or in small sheets -lepidosaurs shed skin in sections or in one big sheet -new layer of keratinized cells grow underneath the old -mucus secretions separate the layers

Answer 81

cranial skeleton may be split into three regions based on development: -brain case (chondrocranium) -gill arches (splanchnocranium) -dermal bone (dermatocranium)

Answer 82

-cartilage braincase -cartilage gill arches (for effective filter feeding, no jaws) -dermal bone covering entire head as shields or plates

Answer 83

braincase: solid bony structure fused with other bones (hold brain in place) gill arches: base of jaw joint, gills in larvae, inner ear bone, hyoids in throat dermal bone: thick solid skull with many bones fused together, major jaw bones, no openings aside from orbits and nares

Answer 84

-movement within the skull between joints of the skull bones -usually occurs between dermal bones and braincase -occurs in most but not all vertebrates -no movement= akinetic (bite harder)

Answer 85

-modern lissamphibia often have reduced the bone in their skull for increased lightness and flexibility -braincase mostly cartilage -gill arch bones remain intact -akinetic -dermal bone reduced or lost in some groups -caecilian skull retains dermal bones for strong head and palate (akinetic) (burrowing) -frog and salamander skull has been lightened and many bones disappeared or become cartilage, wide openings too, reduced palate, reinforce tongue

Answer 86

Early amniotes and parareptiles -had an anapsid skull similar bones to those of early amphibians -akinetic -amniotes eventually lead to the reptiles -they have a pretty robust skull

Answer 87

-changed their skull to make it into the diapsid (two holes) 1. supratemporal fenestra 2. upper temporal bar 3. infratemporal fenestra 4. lower temporal bar (two holes and two bars on either side) (bars used to weave muscle through) (lightens skull) (some have kept this condition today, others have modified it)

Answer 88

-have a diapsid skull -modern skull is akinetic -rigid and powerful, large muscle attachments -large secondary palate -roll to dismember prey and won't rip head off

Answer 89

-modified diapsid skull -all openings have closed up -akinetic -back of skull encroaches forward (emargination) -created processes and openings for increasing muscle size -one of greatest bite forces for their size -more muscle attachment -short skull and beak= nail clippers

Answer 90

-maintain their ancestral diapsid skull and most ancestral bones -akinetic -mandible is loosely connected to the quadrate -allows for jaw to slide forward and back "slicing through prey" -strong jaw and bite -flexible skull but cant eat anything larger than its head

Answer 91

-modified diapsid condition -losing temporal bars -lizards lost their lower temporal bar -snakes lost both upper and lower bars and disconnected mandibular symphyses (extremely flexible) lizards= 4 joints, results in 4 bar linkage chain that allows for the elevation and depression of snout (weird), can pinch prey snakes= greatly reduced bones, 14 moveable parts in total, each side can move separately, can swallow prey larger than head and move both sides separate so it can work its way up the food

Answer 92

-discrete, repeating segments of bone and/or cartilage -the first vertebral elements supported the notochord, provided muscle attachment and protect adjacent features -notochord is the precursor to the spinal column -spinal cord on top and arched bones on bottom (the part you can feel) -either neural or hemal arches -centrum evolved to support the arches -eventually the notochord was replaced by the vertebrae

Answer 93

-anti-twisting -extra muscle attachment -resistance and support -articulation for ribs (often derived from the hemal arches in trunk vertebrae)

Answer 94

-tetrapods have varied degrees of differentiation -trunk=from head to tail (body) -caudal=tail -early tetrapod developed a separation between the head and pectoral girdle= cervical (neck) -articulated the pelvic girdle with the vertebrae= sacral (pelvis)

Answer 95

-caecilians have a long body -larger number of vertebrae -large centra and neural spines -strong back built for burrowing and twisting -many short ribs -very robust and strong vertebrae -hunt with twisting and rolling, need strong

Answer 96

-body built for jumping and absorbing impact -less than 10 vertebrae -one neck vertebrae (for landing on face) -no ribs -very strong pelvis -sacral vert are fused together into rod going vertically down the middle of pelvis -no tail -gave up mobility in back, lots of muscle attachment (strong legs)

Answer 97

-most reptiles have the typical column with ribs running throughout -crocs and unique in that they have no back ribs -have distinct lumber region like mammals -have cervical and caudal vert (typical tetrapod thing going on)

Answer 98

-highly mobile vertebrae (back) -loss of legs means less resistance from girdles and a greater susceptibility to twisting -snakes and some lizards increase the number of interlocking vertebral apophyses -this prevents twisting but does not hinder lateral movement -(snakes twist around prey, don't want to snap in half= apophyses)

Answer 99

-turtle has drastically modified its axial skeleton -vertebrae, enlarged ribs, and dermal bones became the carapace -ribs grow over appendicular skeleton -pectoral girdle and other dermal bones became the plastron -very mobile neck allows for full retraction of the head -lower part of shell made from osteoderms

Answer 100

-embryology indicates that evolutionary development occurred in a similar way -the tetrapod limb evolved from the sacroptergyii fin -the fins bony stem became the majority of the limb bones -herps are not shy about losing their limbs

Answer 101

-needed to change to support body on land -pectoral gridle bones became more robust and disconnect from the head and neck (so no shaking the head with each step) -pelvic girdle expanded into three parts, and articulates with the sacral vertebrae -limb girdles are within the body and support the stuff outside of your body -in order to have limbs, they have to be supported by girdles

Answer 102

-having more than 5 fingers -acanthostega -ichthyostega -then pentydactylous condition was established (5 fingers)

Answer 103

-used to be 2-3-4-5-4 (going up in bones per finger) -now is 3-3-3-3-2 (for humans)

Answer 104

-salamanders have reduced girdles and limbs -pectoral girdle and sternum are mostly cartilage -limb bones have ossified shafts but cartilaginous ends -wrists are cartilage -digits reduced to 4 with 1-3 finger phalanges each -salamanders need to be stored in liquid bc mostly cartilage -reduced size of limbs (simple and can grow back) -anuran have very well developed, ossified limbs and girdles -pectoral girdles are large and fuse at the midline -humerous is thick, forearm bones are fused, wrist is bony, 4 fingers -pelvic girdles form a bony plate in the back that connects with the urostyle -long and bony legs -large feet with 5 toes, long ankle -radius and ulna fused so arm can't twist

Answer 105

-the typical reptile girdles are well ossified and sturdy -pelvic girdle is fused with the sternum, with certain bones lost in certain species -pelvic gridle is triangular, with pubes meeting in the middle and ilia projecting up -reptiles ancestors had short limbs -modern taxa have variable limbs -humerus and femur are longer, smooth, and curved -ulna and tibia are longer than adjacent bones to bear weight -turtle limbs are oriented differently because of the shell -the shell means the ribs grow over the pectoral girdle -the orients the limbs so the elbows face outwards -the girdles fuse to the shell

Answer 106

-pain receptors and thermoreceptors are free nerve endings -several mechanoreceptors detect light tought, pressure, and tension

Answer 107

-lateral line system to detect water currents -retained in larval, paedomorphic, and fully aquatic adult amphibians -pores on inside filled with gel, changes direction with current, sends signal to the brain -neuromasts=ciliary projections

Answer 108

-sensors on the snout of some caecilians and larval salamanders -detect changes in electric fields (prey) -they can tell if there is a charge difference around you -better to use in water

Answer 109

-exist in boas, pythons, and vipers -specialized structures in the skin that house infrared receptors -found on the scales by the mouth or eye -send signals to the brain to detect radiation coming off of animals in pitch black

Answer 110

-all tetrapods have ears of some sort -function to detect vibrations and translate into sound by brain -derived from neuromasts in lateral line -lower to ground=detect low frequency

Answer 111

-outer-ear= ear canal, ends at the tympanum (frogs have no outer ear and tympanum is exposed) -middle-ear= cavity with stapes bone -inner-ear= has several sacs (can be involved with transmitting and balance) -utriculus has semicircular canals which measure momentum -reptiles use cochlear duct to hear with (like us) -vibrations move through bags of fluids and interact with neuromasts)

Answer 112

-typical hollow ball made of sclera (white part), cornea (where contacts go), lens (for refracting light) and retina (which photoreceptors to send to brain) -all reptiles have bones in eyes except snakes -eyes shrink with no need to see (why snake eyes so fucked up, bc think had to re-develop larger eyes from smaller eyes)

Answer 113

-rods detect all wavelengths of light, therefore do not distinguish color -cones detect subsets of visible light= color -frogs have two rods, giving them great light/dark vision -more cones= more color can see

Answer 114

-herps have nasal cavity with olfactory receptors -also have Jacobsen's organ (particles go on tongue (or not), flicked into organ in mouth, can sense the particles around you) -lost taste in tongue

Answer 115

-cutaneous respiration is very important in lissamphibia (skin breathing) -more extensive than in any other group -others have gills and lungs

Answer 116

-salamanders have external gills -these may be waved in the water column to exchange oxygen and CO2 -frogs have internal gills, they have to bring water into mouth or nares -can breathe through nose when attached to a rock by their mouth

Answer 117

-most adult amphibians have lungs -lungs divided into regions by septa -divisions are known as faveoli -amphibian lungs do not branch like mammals -use positive pressure breathing

Answer 118

-bring air into their nose then into the mouth and push air into the lungs -to exhale they push out (negative pressure is when you create dead space and a suctions to bring air in)

Answer 119

-lungs -use negative pressure breathing (like humans) -each lung has single main chamber and several smaller faveoli -some snakes only have one lung

Answer 120

-almost all herps have 3 chambers -crocs have 4 chambers -two atria and one ventricle -does not mix oxygenated and deoxygenated blood (small enough body where don't need two) -crocs evolved from endotherms and just kept the heart which is too complex for their slow metabolism -helpful though bc they can make it so their blood doesn't go to the lungs while underwater to waste air, so they can hold breath longer -some have complex circulatory system bc can breathe through skin

Answer 121

-mouth -buccal cavity -esophagus -stomach -small and large intestines -anus -cloaca (all purpose hole)

Answer 122

-teeth (acrodont, thecodont, pleurodont) -all herps replace teeth regularly (why they usually don't have a powerful bite) -tongue= used to get food, bring particles into jacobsons organs, swallow -lips= don't have facial muscles, so use as seal to keep food in

Answer 123

-singular cavity at the end of the digestive system that receives digestive and urina -also penis come out and put into the same hole -eggs come out of here

Answer 124

-modified saliva -lots of enzymes -breaks down the tissue around it -or stops heart

Answer 125

-originally thought that selection pressure to get onto land was driving force -evidence suggests that metamorphosis first occurred to change the feeding apparatus in adults -these changes later allowed for the invasion of land

Answer 126

-first group of amphibians to branch off from the early tetrapods -these guys did a number, they were huge for the rest of the worlds species and could do anything on land -most aquatic, some partially terrestrial -filled niches similar to modern crocodilians and large fish -includes lissamphibaians and non-lissamphibians

Answer 127

-apart of temnospondyli -did not surivive -abundant for long time, after end of triassic extinction, one group called Koolasuchus survived down south and then died

Answer 128

-early lissamphibians had traits shared by most modern taxa -oldest=frog-amander -traits similar to frogs and salamanders (and is their common ancestor)

Answer 129

-first member of the frog lineage -looked similar to modern frogs but with short legs and a long body -this is the first frog though it didn't look like it

Answer 130

-first caecilian fossil -had its legs back then -slowly kept shrinking until they didn't have them

Answer 131

-closest relative to modern salamanders -have not achieved the long body and tail of modern ones -smaller limps -can see through transitional species showing that bodies slowly but surley morphed into modern body type

Answer 132

-closely related to amniotes -technically amphibians but had many characteristics of reptiles -small/medium sized, terrestrial -filled niches of modern small/medium mammals -comes out of egg ready to go

Answer 133

-branched off from the anthracosaurs -defined by their amniotic egg -started off as small terrestrial taxa -first split in amniotes formed sauropsida and synapsida

Answer 134

Sauropsida= led to reptiles and lizards and shit Synapida= led to mammals and us

Answer 135

-a group developed two fenestra in the temporal region of the skull -all modern reptiles believed to have evolved from this diapsid ancestor

Answer 136

-came about in the triassic -consist of squamata and rhynchocephalian -early members of the group appear similar to modern members, they look lizard-like

Answer 137

-first rhynochocephalian -similar to modern tuatara -group diversified and filled many niches filled by modern lizards -impactor that killed dinos hurt these guys -all moderns are only in New Zealand

Answer 138

-oldest squamata found -not diversify much early on, and remained relativity rare until cretaceous

Answer 139

-first bipedal vertebrates -skull is lightened with an antorbital fenestra (opening in front of the eye) -largest and most diverse land animals ever -were the major vertebrate land fauna -first members of the crocodylian line consisted of small taxa (small and bipedal) -filled medium predator niche -after an extinction of two, these guys diversified and filled more niches -modern croc line arose in early cretaceous

Answer 140

Gavialidae= slender nose, interlocking teeth for squishy prey Alligatoridae= thick nose, over bite Crocodylidae= triangel nose, interlocking teeth (survived extinction by hunkering down and lowing metabolism)

Answer 141

-originally thought to be parareptiles based on fossil -more fossil discovered placed them next to lipidosaurs -genetic evidence puts them just outside archosaurs

Answer 142

First true turtle -had typical turtle body with true shell -ribs and osteoderms fused

Answer 143

teeth sit on top of jaw and fuse to it

Answer 144

teeth sit in sockets

Answer 145

teeth grow on the inside of the jaws (lizards)

Answer 146

side necks when retreating in shell (one eye showing)

Answer 147

straight necks when retreating in shell (both eyes showing)

Answer 148

-egg more costly= female more choosy -sperm is cheap= men are cheap bastards

Answer 149

caused by environmental stimuli, initiating the release of gonadotrophins released from the pituitary gland -not all organisms produce gametes every dat, can be seasonal

Answer 150

-very extremely cheap -can produce millions in a day -highly modified cells built for travel in fluid -have a long propeller or flagella -have an acrosome that has digestive enzymes to get through ova

Answer 151

-ova start off as oogonium -after mitosis, they mature into a primary oocyte -they then divide meiotically into a secondary oocyte -the second meiotic division results in an ovum (1 oogonia-->1ovum) -keeps its mass by shedding off polar bodies= more nutrients

Answer 152

the process of adding yolk to an ovum and wrapping it in a membrane -yolk consists of proteins and lipids

Answer 153

all developing ova are surrounded by non-sex cells which make up a follicle (surrounds egg)

Answer 154

-ova accumulate in the ovary -increase in size with vitellogenesis -the mature ova are deposited into a hypertrophied oviduct (ovulation) -follicles are left behind and deteriorated -in oviduct, ova covered with 3 glycoprotein layers -this jelly covering protects from environment and makes them sticky -fertilization happens either inside or outside -lay a lot of eggs at once

Answer 155

-ova accumulate in ovary and increase in size with vitellogenesis -a lot more yolk is put in reptile eggs than amphibian eggs -ovas deposited into oviduct by follicles (ovulation) -follicles left behind form corpus luteum which produces the hormone progesterone to help with egg development -in oviduct, embryo develops 3 membranes post fertilization -chorion=derived from vitelline membrane -allantois=waste storage -amnion=encases potential embryo -upper oviduct covers the ovum in albumin layers of protein (the egg whites) -calcium introduced determined egg shell hardness

Answer 156

pro: comes out well developed con: expensive, takes time

Answer 157

-occurs in almost all frogs and some salamanders -male graps on female, female lays eggs, male squirts out and fertilizes said eggs, ta da

Answer 158

-sex -most salamanders and all caecillians do this -salamanders produce speratophore and let it go and the female will like sit on top of it (can store if want) -caecilians have an intromitten organ called a phallodeum that extends from cloaca and enters female cloaca to fertilize -turtles and crocs have a penis and squamates have a branched hemipenes

Answer 159

-sex chromosomes determine sex of offspring -usually one parent is heteromorphic (has two types of sex chromosomes, male and female) -occurs in all amphibians and some turtles and squamates

Answer 160

-temp during incubation determines sex of offspring -occurs during second trimester -enzymes production either occurs or doesn't depending on temp, resulting in a sex -occurs in all crocs, tuataras, and some squamates and turtles -no sex chromosomes -don't know why this occurs, no pro -con= can end up with a generation of one sex

Answer 161

-energy is limited, can make lot of small offspring (r-strategist) or small amount of big offspring (k-strategist) -usually based on nature selection operating on eggs, larvae, or young -the amount of food you take in will weigh on your behavior -females devote more time to offspring during seasons with more resources

Answer 162

-bigger females have more nutrients to spare -some lizards will lay more eggs if they are larger -other species will lay the same amount of eggs no matter how big they are, just add more or less yolk -some females can modify both clutch and egg size

Answer 163

-turtles -turtles have rigid pelvis and cannot expand or fit more than capable or will both die -they can only lay eggs that can fit -some species lay larger eggs due to physical constraint -some species lay smaller eggs due to energy constraints

Answer 164

-when is the best time of year to bread? -influenced by temperature and rainfall -amphibians lay eggs in spring time for temperate-zone (warm enough with enough water, avoid winter, higher food availability and low predation)

Answer 165

most reproduce seasonally -temperate-zone reptiles ovulate in spring and lay eggs in summer -length of breeding season is directly influenced by length of the cold season

Answer 166

both males and females have active gonads at about the same time

Answer 167

male gonads are active first, followed by females (sperm stored for later use by females)

Answer 168

gonads are always active, except when female is gravid (pregnant)

Answer 169

-sexual reproduction in herps is the fusion of male and female gametes (fertilization) -some females herps reproduce without a male (unisexual) -three methods exists: hybridogenesis kelptogenesis parthenogenesis

Answer 170

-results when two species breed and produce a hybrid (half female, half male shit) -the resulting hybrid female does not contribute the males genes into the offspring after mating -next generation is all female, and contain only her genome

Answer 171

-results when two species breed and produce a hybrid species -this hybrid incorporates a select few (or none of ) the chromosomes form the male -means to steal genes when it wants -result is either a clone, or a polyploid (2n-5n) offspring

Exam I Flashcards

(198 cards)