Buoyancy Flashcards
State the ways in which fishes achieve buoyancy (both active and passive/static ways).
1) Using pectoral fins for general lift
2) Substituting protein for fat or lipids and by substituting calcifying bones for cartilaginous ones.
3) They have a swim bladder to help with lift.
What type of fishes does not have a swim bladder?
1) Pelagic fishes like the nototheniidae
2) vertical migrators
3) fishes that swim continuously over wide depths
What percentage of bony fish have swim bladders?
50%
What are the types of swim bladders?
physoclistous and physostomous
What is the three ways of lipid storage within fishes?
1) Squalene
2) Wax esters
3) Lipids
What are the advantage and disadvantages of storing lipids within the fish?
Dis: fine-tuning is difficult & Buoyancy linked to metabolism
Ad: Buoyancy does not vary with depth.
What is the advantage and disadvantage of reducing dense materials like calcified bones?
Dis: Restricted movement
Ad; Buoyancy doesn’t vary with depth
How do fishes generate general lift? which is an active way of gaining buoyancy.
By using their pectoral fins
What is the advantage and disadvantage of general lift/ actively achieving buoyancy ?
Dis: High energy is required & must maintain a certain speed
Ad: Can move freely up and down through the water column.
What is buoyancy?
How fishes maintain their vertical position within the water column
True or false? Primitive fishes had a gas bladder and lacked lungs.
False. Primitive fishes has lungs and due to evolution developed gas bladders instead which are known as swim bladders.
What are the three purpose of the gas bladder/ swim bladder?
1) To detect sound
2) Produce sound
3) Achieve buoyancy.
How does the swim bladder achieve buoyancy?
By adjusting the amount of air that fills the bladder. Aka changing the size of the bladder.
Which type of swim bladder lacks a pneumatic duct?
Physoclistous. It has a network of capillaries that help transport gases to the bladder to change its size.
Which swim bladder has a pneumatic duct?
Phytsostomous. Fishes with this type of swim bladder swims to the surface of the water and gulp for air. To release air they burp.
What is the disadvantage of the physostomous swim bladder?
dis: Fine tuning is difficult
Which swim bladder derivedd from the primitiave sac?
Physostomous
what connects the swim bladder to the gut in the physostomous swim bladder?
The pneumatic duct
How was the physostomous bladder derived?
dervied as out pocket from gut.
Where does the gas exits in the physostomous bladder?
Pneumatic duct
How does the physostomous bladder colelct air?
Gulping or diffusion from gas gland
Name the four secretion methods for gas into ad out of the swim bladder.
Root and Bohr effect, Salting out, Rete Mirable and countercurrent exchange
True or false. A fixed amount of gas will have greater buoyancy at greater depths.
False.
Think about it and provide an explanation.
How does the physostomous swim bladder add and release gas?
Gulping via the Rete mirable and gas gland
Burping via pneumatic duct
