week 10, apr 18th - 22nd Flashcards
Describe phylum chordata
Invertebrates (no backbone)
Vertebrates (backbone)
Coelomates
Deuterostome
State the 5 common features of chordates
1/2 = dorsal and hollow nerve cord 3 = notochord 4 = pharyngeal gill slits 5 = post anal tail
Who were the ancestors to vertebrates
Jawless fishes
Has sucker
Evolved a jawbone from fusing gill arches
Name the species in class chondrichthyes
Shark
Ray
Describe class chondrichthyes
Cartilaginous fishes Have cartilage, no bones Backbone composed of vertebrae - cartilage No buoyancy Internal fertilization Some give birth to live youngs More advanced heart than bony fishes
Describe internal fertilization
Delivering sperm inside the female
More efficient than external fertilization
Describe animals in Class Actinopterygii
Bony fishes
Describe Class Actinopterygii
Buoyant
Describe components of the respiratory system of Class Actinopterygii
Gills - composed of many gill filaments
Operculum to ventilate and movie water through gills
Describe the respiratory system of Class Actinopterygii
Oxygen rich water enters the mouth and leaves through the gill slit
Gas exchange by simple diffusion - passive transport
Describe the counter current system of Class Actinopterygii
Maximum loading of oxygen in gills
Water flows in opposite direction of the blood flow (oxygen poor blood)
Deoxygenated —> oxygenated (same direction)
Mouth —> gill slit (water flows opposite to blood) = allows oxygen to be picked up on both sides
Describe circulatory system of vertebrates
Closed circulatory system = blood circulated within blood vessels with blood pressure
Describe circulatory system of bony fishes
Closed circulatory system
One circuit - slow
Two chambered heart
Ectotherms = cold blooded
Describe two chambered heart of bony fishes
One atrium receives blood
One ventricle sends blood out
Why the is one circuit slow in circulatory system of bony fishes
The oxygen rich blood leaving gills do not return to the heart
It goes to all organs first
Oxygen poor blood returns to heart
Heart never receives oxygen rich blood
Describe features of bony fishes (fertilization)
External fertilization
Female lays unfertilized eggs
Male secrets sperm over eggs
No parental care
Name species in class amphibia
Frogs
Salamanders
Explain characteristics of class amphibia
Invaded land
Evolved limbs from fins
Still dependant on water for reproduction and respiration
Describe fertilization of class amphibia
External fertilization Lays eggs in water Metamorphosis Tadpole (gills, herbivores) —> adult frog (lungs, carnivores) Cryptic egg
What is a cryptic egg
See dark part from above and can’t see it from below
See light part from below and can’t see if from above
Describe respiration of class amphibia
Need moist skin to add oxygen to blood
Adults have positive pressure breathing system = force or push air (needs energy) in their lungs which have a higher pressure than atmosphere
Describe circulatory system of class amphibia
Closed
Evolved two circuits
Evolved three chambered heart
Cold blood - ectotherm
Describe circulatory system (two circuits) of class amphibia
Pulmocutaneous circuit (lungs and skin) Systemic circuit (all organs except lungs)
Describe circulatory system (three chambers) of class amphibia
Two atria
Right atrium receives oxygen poor blood
Left atrium receives oxygen rich blood
One ventricle receives oxygen rich and oxygen poor blood (mixing blood) = sends poorly oxygenated blood to organs
