Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biodiversity > Lecture 15: The Amniotes > Flashcards

Lecture 15: The Amniotes Flashcards

1
Q

Amniotes:

A

Reptiles and birds + mammal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

The amniotes…

A
  • a self-contained waterproof chamber for development, eliminates the larval stage.
  • contains 4 membrane layers that are not part of the embryo.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Yolk sac…

A

Surrounds the yolk nutrients, which is accumulation of nutrients that surrounds the embryo.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Allantois…

A

stores nitrogenous waste, stores all waste from the embryo. Lies against the chorion so also involved in gas exchange.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 types of Amniote based on..

A

number of fenestra (windows) in the skull

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

No fenestra, turtles, extinct reptiles..

A

Anapsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Two fenestra, other reptiles, birds…

A

Diapsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

One fenestra, mammals…

A

synapsid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Reptiles:

A
  • 7000 species, many extinct lineages
  • paraphyletic (multiple lineages) [isnt a single ancestor from all the reptiles]
  • lack of single defining characteristic, other than have an amniotic egg, no feathers (not birds)
  • inc. turtles, lizard, snakes, crocodiles, tuatara
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Reptile features:

A

-dry scaly keratinised skin, prevents desiccation and UV
-internal fertilisation, eggs laid on land
-ectothermal -regulate their temp through solar energy
-heavier more ossified skeleton than amphibia, stronger joints, clawed toes
-more complex muscle and nervous systems
4 chambered heart separates oxygenated and deoxygenated blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

ectotherm + & -

A

pos
-eat less than endotherm (10% of what endotherm eat)
neg
- slow in cold weather therefore vulnerable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Evolution history of reptiles..

A
  • oldest fossile date to the carboniferous (300mya)
  • early forms probably fed on invertebrates
  • penetrated further inland than amphibians
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

(reptiles) first amniote radiation in the Permian led to…

A

anapsid, synapsids and diapsids; diapsids led to lepidosauria (lizards and snakes) and archosauria (crocodiles&dinosaurs)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

(reptiles) Second radiation of archosauria led to..

A

dinosaurs etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Most reptiles of sustained rapid motion..

A
  • stride is short
  • proximal limb segments move on the horizontal plane
  • ectothermic, glycolysis rather than oxidative metabolism
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Dinosaurs endothermic?

A
  • legs beneath body
  • long strides
  • vascularised bones (blood in bones)
  • predator prey ratios (similar to present day mammal)
17
Q

dinosaurs ectothermic?

A
  • warm Mesozoic

- surface area to volume ratio (high temp maintained by storing heat in there bodies, lost heat relatively slowly)

18
Q

dinosaurs extinction theories?

A
  • rise of the mammals
  • explosion (volcano?) lots of particulate matter and not enough sunlight.
  • asteroid impact

Now scientists believe asteroid impact caused change in climate (climate change)

19
Q

Modern reptiles 3 main orders

A
  • chelonia (turtles)
  • squamata (ilzards and snakes)
  • crocodilia (alligators and crocodiles)
20
Q

Order chelonia (turtles)

A
  • 250sp
  • includes marine, freshwater and terrestrial types
  • teeth replaced by sharp horny plates
  • bony dermal plates fuse to form carapace and plastron
  • flexibile neck
21
Q

Order squamata (ilzards and snakes)

A
  • lizards (4000 sp)
  • snakes (2500sp), highly specialised
  • loss of limbs, elongate body form,likely burrowing ancestor
  • loss of eyelids, have clear spectacle
  • many specialisations for finding prey
    • jacobson’s organs senses smell
    • pit organs sense heat (endothermic prey)
  • jaws extremely flexible with moveable joints for large prey.
22
Q

Order crocodilia (alligators and crocodiles)..

A
  • 22spp

- all extant species …………….

23
Q

Class Aves (birds)

  • how they defined
  • phyletic group?
  • reptile features that are present
A
  • defined by the presence of feathers
  • monophyletic group
  • reptile features include scaly legs, amniote eggs (reduces water loss, calcium carbonate)
24
Q

Aves characteristics…

A
  • honeycombed bones with cross struts
  • reduced organs (e.g. females have 1 ovary)
  • no teeth, food ground in gizzard
  • keratin bill (modified, hooke bill for tearing flesh, humming bird long thing bill for nectar)
  • large pectoral muscle anchored to keel with rigid fused vertebrae gives power for flight
25
Q

wings and feathers…

A
  • aerofoil shaped wing, leading edge thicker, following edge thinner???????????????????????????
  • pentadactyl limb (no longer 5 digits)
  • feathers held together with barbs and hooked barbules
26
Q

feathers…

A
  • consist of shaft, barb, barbules with hooks

- outgrowths of skin made from keratin, not living

27
Q

Aves endothermic or ectothermic??

A

Endothermy, fat and feather insulation.

(penguins)Can also pull blood up from their feet to avoid losing heat to cold ice.

28
Q

aves heart..

A

4 chambered heart, efficient circulation

29
Q

aves brain and intelligence..

A
  • large brain
  • complex behaviour
  • colour vision (more cones than rods)
  • capable of learning
30
Q

Evolutionary origin of birds..

A 
Arose from bipedal dinosaur therapy (e.g. t-rex)
-earliest forms
   - bird like
          -feathers
          -aerofoil wing 
          -large eyes and brain 
   -reptile-like
          -teeth 
......!!!!!!!!!!!!!!!!!!!!!!!!
31
Q

Origin of flight 2 hypothesis’..

A

1) ancestors were arboreal climbers (claws) and feather evolved as an adaption for gliding to the ground
2) ancestors were sartorial, chasing insect prey, feathers evolved as an adaption for catching and later aided rapid running, jumping and gliding.

32
Q

Modern bird diversity,

2 big groups:

A
  • Ratites (“raft shaped” or flat chest)

- carinates (have keel or carina)

33
Q

Ratites…

A
  • once thought primitive but has evolved at least four time
  • cassowary & emu, kiwi, ostrich, rhea - not monophyletic
  • lack keel but have wide sternum suggests………
34
Q

Carinates….

A

24 orders, 8,600 species

- gr………………….

35
Q

4 Extraembryonic membranes:

A
  • Amnion (protection)
  • Allantois (waste, gas exchange)
  • Chorion (gas exchange)
  • yolk sac

Biodiversity (11 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions