fish

Question 1

what are the features of a fish

Answer 1

vertebrates, almost all aquatic, fins gills and scales

Question 2

what are some important aspects of fish

Answer 2

most diverse extant vertebrates, first vertebrates, food and economics, recreation and tourism

Question 3

what are some external anatomical features of fish

Answer 3

scales, lateral line, fins (median and paired)
gills (elsomobranch 5-7 pairs)
teslosts 4 pairs and gill cover

Question 4

what purpose does the lateral line serve

Answer 4

sensory organ to detect movement and changes in water pressure

Question 5

what function do gills serve

Answer 5

respiration and osmoregulation

Question 6

how do gills preform osmoregulation

Answer 6

by way of chloride cells which are rich in mitochonria and most atp in any cell, found at base of second lamellae

Question 7

what are the key evolutionary steps found in fish

Answer 7

jaws and protusable jaws
fine motion control

Question 8

what are jaws formed from and mention the function and makeup of protusable jaws

Answer 8

made of fused anterior gill arches, protusable jaws have ligamentous connections between free floating bones
increases attack speed and pulls items into jaws

Question 9

what and why are paired fin positions important

Answer 9

in the anterior positioning of pelvic fins allows for increased manoeuvrability and fine control
this allows for complex habitats like coral reefs
it requires a gas bladder for neutral buoyancy

Question 10

what internal anatomy and organs do teleosts have

Answer 10

digestive tract, liver
spleen pancreas or pyloric caeca
kidney
urinary bladder
gonad
swimbladder

Question 11

how do the internals of sharks and rays differ from that of teleosts

Answer 11

they have a discrete pancreas
a rectal gland
intestines have spiral glands

Question 12

what is the origins of tetra pods

Answer 12

lobe finned fishes such as coelacanth and lungfish
fossils such as tiktaalik from 375 mya