The AER,the Thickened Ectoderm at the Distal Tip of the Limb

question 16

Multiple Choice

The AER,the thickened ectoderm at the distal tip of the limb bud,controls limb outgrowth.Genetic inactivation experiments in mice and manipulation studies in chicks have identified the key factors expressed in the AER that control outgrowth once the limb bud has formed.What family of growth factors in the AER promotes outgrowth?

• A) Bmp
• B) Fgfs
• C) Wnts
• D) Shh

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Definitions:

Factor Endowments

The quantity and quality of labor, land, and capital that a country possesses and can utilize for manufacturing.

Free Trade

A policy wherein a government does not discriminate against imports or interfere with exports by applying tariffs (to imports) or subsidies (to exports).

Tariffs

Government levies on goods brought into the country.

Import Quotas

Import Quotas are government-imposed limits on the quantity or value of goods that can be imported into a country, typically used to protect domestic industries and control trade balances.