Exam 1 ehh Flashcards
What are the factors that affect the efficiency of gills?
1) Diffusion distance
2) Surface area
3) Concentration gradient
What are 3 factors that affect diffusion distance?
- Structure of lamellae (2 cells thick)
- Mucus (enhance ion exchange)
- # of lamellae per filament (want more)
How is surface area increased?
- More lamellae per filament
- Larger lamellae
How do you increase the concentration gradient to increase diffusion speed?
- Rapid ventilation
- Counter-current ventilation
What kind of gills do lampreys have?
Pouched gills
What kind of gills do Chondrichthyes have?
septal gills
What kind of gills do Osteichthyes have?
opercular gills
What kind of mechanism do lampreys use?
tidal ventilation (pump water in and out in same opening) - means no counter-current ventilation
What 2 mechanism do sharks use?
(unidirectional ventilation)
- ram ventilation
- buccal ventilation
What kind of mechanism do Osteichthyes use?
opercular pumping
What is the swim bladder used for?
used to float and stay in one position
What is physostomes?
- gulp air and force into swim bladder
- burp to release
What are physoclists?
- Cells around bladder generate lactic acid
- lowers pH in capillary bed
- Causes hemoglobin to dump o2 in bladder
What is the lateral line used for?
- Detects water displacement (predator detection)
What makes vertebrates distinguishable from other animals?
1) Cranium
2) Duplication of HOX gene complex
3) Neural crest cells
4) Enlarged, tri-partitle brain
5) Placodes
6) MicroRNA
ALL vertebrates have similar body plans
(same phylum)
