Sponges Are Generally Protected from Predators by the Presence of Calcium

question 40

Multiple Choice

Sponges are generally protected from predators by the presence of calcium and silica crystals. These crystalline structures are called

• A) amoebocytes.
• B) osculum.
• C) choanocytes.
• D) spicules.
• E) spongin.

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Definitions:

Unit Elastic

Describes a demand or supply situation where a change in price leads to a proportional change in the quantity demanded or supplied.

Total Revenue

The total income generated by a business through the sale of goods or services before any costs or expenses are deducted.

Downward-sloping

A graphical representation indicating a negative relationship between two variables, such as price and quantity demanded in the demand curve.

Elasticity of Demand

A measure of how much the quantity demanded of a good responds to a change in the price of that good, quantitatively expressed as the percentage change in quantity demanded divided by the percentage change in price.