It Is Thought That Jaws, Which Are Found in the Higher

question 39

Multiple Choice

It is thought that jaws, which are found in the higher vertebrates, evolved from

• A) cartilaginous arches used to support gills.
• B) small bones associated with the brain capsule.
• C) the bony teeth found on lamprey tongues.
• D) progressive hardening of the cyclostome mouth.
• E) None of the above

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Definitions:

Pars Nervosa

The posterior part of the pituitary gland, which releases hormones stored in axon terminals from the hypothalamus.

Electrolyte Concentrations

The measure of the levels of electrolytes, such as sodium, potassium, and chloride, in the body, critical for maintaining proper fluid balance and muscle function.

Extracellular Fluids

Fluids outside of cells, including blood plasma and interstitial fluid, that help transport nutrients, oxygen, and waste products.

Blood Calcium

The concentration of calcium ions in the blood, which is crucial for bone health, muscle function, and nerve signaling.