Mesozoic and amniotes Flashcards Preview

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Flashcards in Mesozoic and amniotes Deck (16)
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1

Describe the key features of the Triassic:

-A great radiation of reptiles began -Its end was marked by a mass extinction event due to the impact of a meteorite -O2 levels drop to 15%

2

Describe the key features of the Jurassic period:

-Pangea become fully divided into Laurasia and Gondwana -Dinosaurs become the dominant large vertebrates -High levels of CO2 and O2 drops even more (11%)

3

Describe the key features of the cretaceous:

-Laurasia and Gondwana break apart into smaller continents. -Radiation of flowering plants

4

What are the terrestrial causes of extinction?

-Ecosystem can be really fragile due to their connectivness -Changing in the geology of the habitat -Biochemical properties of the atmosphere

5

What are the possible extra-terrestrial causes of mass extinction?

-Bolides -Transit through Spiral Arms/Gamma Burst

6

What are the two main cause of the PT extinction?

-Eruption of two bigs volcano -Breaking up of Pangea.

7

What are the three different types of skull?

-Anapsid -Synapsid -Diapsid

8

Describe the anapsid skull:

It has no fenestration at all.

9

Describe the synapsid skull:

A single lateral opening, no temporal opening behind the orbit.

10

Describe the diapsid skull:

Has two temporal openings.

11

What are the four components of an amniotic egg?

1) Amnion 2) Allantois 3) Chorion 4) Yolk sac

12

What are the features that distingush archosauromorpha?

-The presence of an antiorbital fenestra (in front of the eye). -4th trochanter on the femur

13

What are the features that distinguish crocodilians from other archosaurs?

-Development of a secondary palate -They have nostrils on the tips of the snout. -They have a septum in their heart.

14

What are the characteristics of lepidosauromorpha?

The skull has a dorsal temporal opening but lacks a lower temporal fenestra.

15

What are the characteristics of non-avian reptiles?

-Waterproof outer layer to protect from the dry environment. -They mute their skin -Developed new kind of kinetic jaws connected by elastic ligament -New sensory systems (thermal sensors).

16

What are the similarities between birds and therapods?

1) They have a S-shaped neck. 2) Hollow, pneumatic bones.