Fish

Question 1

What is a grade?

Answer 1

taxon united by a level of morphological or physiological complexity

Question 2

Are fish a grade or a clade?

Answer 2

grade

Question 3

Give 3 characteristics of agnathans

Answer 3

jawless, 
no paired fins, 
2 chambered heart, 
7+ gill pouches, 
notochord in larvae and adults

Question 4

What is a strange characteristic of hagfish considering they are vertebrates?

Answer 4

they have no vertebrae (just a fibre-sheathed notochord)

Question 5

What type of lifecyle do lampreys have?

Answer 5

anadromous

Question 6

What is an anadromous lifecycle?

Answer 6

start in freshwater (streams, lakes, rivers, etc.), migrate to the ocean, then return home to spawn and die

Question 7

What are some major evolutionary transitions between agnathans and gnathostomes?

Answer 7

jaws, duplication of HOX gene complex, well-developed lateral line, ribs, 2 nostrils..

Question 8

What developed into protojaws during the evolution of jaw?

Answer 8

madibular gill arch

Question 9

What are pleiotrophy genes?

Answer 9

More than 1 effect

Question 10

What developmental toolkit gene is upregulated to reduce eye structure and increase tastbuds?

Answer 10

Hedgehog

Question 11

What are the sensory hairs all over fish called?

Answer 11

Neuromasts- bending = feedback

Question 12

What are the 2 types of neuromasts?

Answer 12

superficial and canal

Question 13

What are statocysts used for?

Answer 13

orientation - in inner ear

Question 14

What are the 2 different swimming types and their benefits?

Answer 14

1- body/caudal fin- good thrust and acc.

2- median/paired fin- good manouverabilty

Question 15

What is an example of an anguilliform swimming type?

Answer 15

eel

Question 16

What is an example of a carangiform swimming type?

Answer 16

trout

Question 17

Why is there high propelllor efficiency?

Answer 17

As acting on large vol. of water

Question 18

What are the 3 main forms of drag?

Answer 18

skin, shape pushing and vortices

Question 19

What are 2 classifications of fish?

Answer 19

bony and cartilagionous

Question 20

What are some major problems with aquatic existence?

Answer 20

density of water, need gases for resp., buoncy and temp. regulation…

Question 21

What does ossification of dermal elements in Osteichthyes mean?

Answer 21

scales become bony

Question 22

What is a major change is bony fish skeleton over time?

Answer 22

thinner and lighter

Question 23

What is the difference between CYCLOID and CTENOID scales on teleosts?

Answer 23

cycloid- primitive- annual growth rings

ctenoid- fast swimmers- serrated edges = microturbulence = reduce drag

Question 24

Why does teleost skin appear silvery?

Answer 24

As reflective guanine layers under skin

Question 25

what are shark placoid scales?

Answer 25

‘dermal denticles’ - dont grow + same structure as a tooth (3-layers)

Question 26

What are the gills enclosed in in teleoosts?

Answer 26

opercular cavities

Question 27

How do sharks maintain bouyancy without swim bladder?

Answer 27

Vast liver, rich in squalene = neutral body density

Question 28

What is fercundity?

Answer 28

ability to produce an abundance of offspring

Question 29

What are perpetual swimmers?

Answer 29

lost function to pump current over gills os have to keep swimming with mouth open for respiration

Question 30

How does a physoclists swim bladder work?

Answer 30

o2 carrying capacity of blood dependant on pH , therefore use lactate transfer from out to in vessels at gas gland on ventral bladder wall to liberate 02 into swim bladder

Question 31

What is an example of regional heterothermy?

Answer 31

muscles warm up in TUNA

Question 32

How marine do teleosts regulate osmolarity and ionic?

Answer 32

drink, little urine, excess NaCl out of gills

Question 33

What is an example of an adaptation to low CO2?

Answer 33

air-breathing e.g. big lips and true lung also bubble nests (make Betta fish)