More about Cartilaginous fish

1. Explain how cartilaginous and bony fish regulate the salt found in water?

By Osmoregulation cartilaginous and bony fish control the levels of water and mineral salts in the blood. Bony fish deal with this uneven concentration by drinking a lot of seawater to stay hydrated and excreting the concentrated salts through the gills and gut.  Sharks have evolved the ability to reabsorb the urea created by the breakdown of protein back into their tissue which helps level out the concentration differences so they do not lose as much water. 


2. What are some key differences in LIFE HISTORYs between cartilaginous and bony fish?

The difference in these two strategies magnify why sharks and bony fish need to be managed in different ways.  Bony fish on the fast track have the ability to replace itself in a population quickly but all of the characteristics listed above mean sharks take a lot longer.

3. Describe how shark reproduce.

All shark reproduction is internal.  Male sharks have mixoptyerigia, or pelvic claspers, an extension of the cartilaginous skeleton that serve as the sperm conducting structure for internal fertilization.  

What are Cartilaginous fish?

1.What makes cartilaginous fish different from other fish? Give examples

One of them is ‘Class Chondrichthyes’, which includes sharks, rays and chimeras. This class of fish is also known as ‘cartilaginous’ fish because they have skeletons made of cartilage. The other class is ‘Class Osteichthyes’, which gave rise to the modern day bony fish, also called ‘teleost’, and their primitive relatives such as the sturgeon.  Although the two groups once shared a common ancestor, there are several major biological differences between them.
2.List examples of cartilaginous fish.

Bony fishShark 
3.What’s special about a shark’s eye?

Shark species have eyelids and some can even protect their eye with a tough third eyelid called a nictating membrane.  Other species, like the great white shark, have muscles that can roll the eye back into the socket for protection.  Bony fish lack eyelids or the ability to protect their eyes.4.What are the differences between bony fish and cartilaginous fish:

a.Heart and bloodb.External features
c.Digesting and evacuation

Marine Anthropoids

1-What are examples of marine arthropods?

The sub-phylum Crustacean, the class merostomata, cleaner shrimp, hermit crab

2- What's the different between an anthropoids skeleton and a human?

Anthropoids is made of a tough substance called chitin, the muscles of an anthropoids are connected to inside of the exoskeleton because the animals lacks a internal skeleton of any type.

3- Compare and Contrast how anthropoids  and humans move blood in their circulatory systems?

Open circulatory its what is called and this means that unlike many other kinds of animals they have no arteries veins or capillaries to carry blood. instead blood is pumped.

4- How do the eyes of anthropoids differ from your eyes?

Each eye is composed of many smaller light-sensitive organs, called ommatidia, together, these ommatidia form a single working eye.

5- How do humans use marine anthropoids?

We mainly use for food.

Marines Science Words of Wisdom.

Grey whale mothers nurse their babies for 6-8 months giving them rich milk which allows them to

quickly gain the blubber they will need in colder waters. However, the mother barely eats during that

time and loses 1/3 of her body weight. She is near exhaustion by the time she and her calf begin their

10,000 mile migration to the Bering Sea.

End of the line, Pt 2 - Movie -

BIG QUESTION: Why should we humans be concerned about overfishing?
Because we're unbalancing marine life.

1. What are the "Big Five" fish we eat all the time?


Atlantic Salmon (organic farmed)
Atlantic Halibut (onshore farmed)
Coley or Saithe (NE Arctic)
Dab (otter trawl or seine net)
Herring (MSC certified)
Mussel
Pouting or Bib


2. What is a reason for not eating sharks or other deep water fish?


They may also be recovering from previous
over exploitation, species with relatively low resilience to
modern fishing methods, or fish from farming systems
that need to improve some of their practices.


3. What are some "fish to eat" occasionally and "fish to avoid"?

Fish to eat:


Alaska or Walleye Pollock
Anchovy
Arctic char
Bream
Gilthead


Fish to eat only occasionally:


Flounder
Grey mullet
Gurnard
Haddock
Hake
Halibut
Herring or Sild
Mackerel
Marlin
Monkfish (Anglerfish)


Fish to avoid:


Prawn (King and Tiger)
Red Mullet
Salmon
Sardine or Pilchard
Scampi or Langoustine
Seabass
Shark & Dogfish (rock salmon)
Skate and Rays
Sole (Dover/Common)