Flashcards in Fish biomechanics and locomotion - Part 1 Deck (53)
What constrains fish swimming?
Habitat (pelagic vs. structured; lentic vs. lotic)
How does the environment/habitat of a fish affect swimming?
Where the fish is living affects how the fish swims and the morphology it needs.
How does body shape constrain swimming?
Streamline or chunky
How does temperature affect swimming ability?
Direct effect on swimming speed since fish are poikilothermic, warmer water means faster swimming.
Current feedsback on fish _______.
Salwater is more ______ than fresh.
Size and shape of a fish affects how _____ it is to move through water.
A fish can have different _____ _____ for size if it changes habitats.
For most fish (like trout), what are the main swimming muscles?
Describe the basic swimming mode in fish.
Bend the trunk muscles in contractile waves to propulse themselves.
Bend one side and push against the water, then the other side.
What are the different muscle blocks in trunk muscles called?
Myotomes or myomeres
What is the membrane between individual myotomes called?
What does epaxial mean?
Epaxial - above the midline
Hepaxial - below the midline
Describe muscle trunk contraction.
If a myotome contracts, it pulls on the myoseptum and the one side of the body moves.
Describe fish swimming .Include myomeres in your answer.
When a fish wants to swim, contracts one set of myomeres on one side of the body, the the other, alternate contractile waves.
When it does this, pushes against the water, and the water will push back against the fish, providing forward thrust.
Does this in a contractile wave from head to tail.
Water will resist ______.
______ is caused by going through a dense medium.,
______ counteracts thrust, need density of water to push against but _____ is anything that impedes _____.
How can drag be minimized to increase thrust? (i.e. what does drag depend on)
Drag depends on density and fish size and shape.
Describe lift in a fish.
As water flows over the fish, generates lift, since there is a negative pressure zone on the top.
The faster a fish swims, the more _____ is generated, fish shape affects ______.
(although other possible answers too)
Why is there a negative pressure zone above the fish?
When a fish swims, get flow separation, flows above and below.
This causes a vacuum above or a negative pressure zone, producing lift.
What is roll?
Tendency of a fish to roll over due to water pushing against it.
Fish that have to worry about roll will have what body type to counteract it?
Fish will have higher bodies (i.e. sunfish)
High means dorsal-ventral is larger (aka deep bodied)
How do fish counteract roll?
By flaring their fins out to act as breaks (in addition to high bodies)
What is pitch?
Movement of head up and down.
When is pitch prevalent?
For fish that swim more with their tail than their body.
How can pitch be counteracted?
Flat head like hammerhead shark or, stick pelvic fin out
What is yaw?
Movement of whole body from left to right