Lab VI - Evolution of Vertebrates

Question 1

What is the function of the cardiovascular system?

Answer 1

transport nutrients, wastes, hormones, gases, etc. to the various cells/tissues of the organism

Question 2

What are vertebrates

Answer 2

animals that possess heads and spinal cords

Question 3

Many animals such as WHAT (2) possess an open circulatory system?

Answer 3

arthropods & molluscs

Question 4

What do arthropods & mollusks circulate in their body (hint: not blood)?

Answer 4

hemolymph

Question 5

Why do capillaries have thin walls?

Answer 5

allow materials to be exchanged b/w blood and cell

Question 6

is the flow of the blood unidirectional or bidirectional?

Answer 6

UNIdirectional

Question 7

Due to what is our blood flow unidirectional?

Answer 7

due to valves (they prevent backflow)

Question 8

What do the organs in the respiratory system provide? (2)

Answer 8

• O2 from air/water to diffuse in blood
• CO2 to diffuse out of blood into air/water

Question 9

which characteristics do all respiratory surface organs have in common that helps them accomplish these functions? (3*)

Answer 9

• large & thin surface area for exchange
• extensive network of capillaries
• ALWAYS moist environment

Question 10

What respiratory organs do fish use?

Answer 10

gills

Question 11

What respiratory organs do amphibians use?

Answer 11

skin & lungs

Question 12

What respiratory organs do mammals use?

Answer 12

lungs

Question 13

Can a reptile breathe underwater like a fish or an amphibian?

Answer 13

NO, b/c amphibians can breathe through their skin & fish with their gills
AND reptile can only breath using their lungs

Question 14

Main function of heart

Answer 14

pump blood

Question 15

Main function of veins

Answer 15

blood vessels responsible for moving blood TOWARDS the heart

Question 16

Main function of arteries

Answer 16

blood vessels responsible for moving blood AWAY the heart

Question 17

Main function of the respiratory system

Answer 17

exchange gases (O2 & CO2) with the env.

Question 18

If organism has a more efficient respirator/cardiovascular system, what would be the outcome? (3)

Answer 18

• higher metabolism
• able to thermoregulate
• faster movements

Question 19

How many heart chambers do fish have?

Answer 19

2 heart chambers: 1 atrium + 1 ventricle

Question 20

How many closed circuits do fish have?

Answer 20

1 closed circuit

Question 21

TRUE or FALSE: fish oxygen-rich and poor blood mix

Answer 21

FALSE, they don’t mix, b/c they have one closed circuit

Question 22

How many heart chambers do amphibians have?

Answer 22

3 chambers: 2 atrium + 1 ventricule

Question 23

How many closed circuits do amphibians have?

Answer 23

2 closed circuits

Question 24

YES or NO for blood-mixing in amphibians

Answer 24

YES, blood mixing

Question 25

How come is their blood mixing in amphibians?

Answer 25

b/c they have 2 circuits but they are PARTIALLY separated

Question 26

How many heart chambers do mammals & birds have?

Answer 26

4 heart chambers: 2 atrium + 2 ventricles

Question 27

Is their blood mixing for mammals & fish? why?

Answer 27

NO, b/c 2 circulations circuits are COMPLETELY separated

Question 28

Which reptiles have 3 heart chambers?

Answer 28

NON-crocodilians (turtles) 2 atriums + 1 ventricle

Question 29

For NON-crocodilians reptiles, how many circulation circuits do they have?

Answer 29

2

Question 30

Is their blood mixing for NON-crocodilians reptiles? why?

Answer 30

YES, it does minimally b/c of partial septum

Question 31

How many heart chambers do crocodilians have?

Answer 31

4 chambered heart = 2 atriums + 2 ventricles

Question 32

Is their any blood mixing if there is 4 chambers? (yes or no)

Answer 32

YES

Question 33

How come?? Although crocodilian reptiles have a 4-chambered heart and COMPLETE separation of oxygen-rich and oxygen-poor blood at the level of the heart, how does this happen (blood mixing?)

Answer 33

B/c of the foramen Panizza

Question 34

Explain more about the foramen of Panizza

Answer 34

oxygen-poor blood from the bypass aorta during periods of APNEA can mix with oxygen-rich blood from the main aorta via a HOLE between these aortae (foramen Panizza)

Question 35

What are tetrapods?

Answer 35

mammals, birds, amphibians & reptiles

Question 36

Give examples of amphibians

Answer 36

salamanders, newts, frogs, toads

Question 37

Give examples of NON-crocodilians

Answer 37

turtles, lizards, snakes

Question 38

Give examples of crocodilians

Answer 38

crocodiles, alligators, caiman

Question 39

Through common ancestor, name all of them from left to right

Answer 39

Fish, Amphibians, Mammals, Reptiles, Birds

Question 40

What does convergent evolution mean?

Answer 40

same or similar traits/characteristics but they are NOT related (no common ancestors)

Question 41

Are mammal and birds analogies or homologies?

Answer 41

ANALOGIES (evolved indepently (no common ancestor)) (homologies -> same ancestor)