Why Is a Bird-Foot Delta Like That of the Present-Day

question 40

Multiple Choice

Why is a bird-foot delta like that of the present-day Mississippi below New Orleans likely to change naturally toward one with the shape of an equilateral triangle like the upper-case Greek letter delta (̇Δ) ?

• A) Increased sediment loads since the mid-19th century have caused the major distributaries to be filled with sand.
• B) Present-day distributaries have higher gradients than potential new ones.
• C) Potential, new, distributary channels have higher gradients, causing downcutting of the existing channels.
• D) Potential, new, major distributary channels have steeper gradients than existing channels.

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Definitions:

Stress Hormones

Hormones, such as cortisol and adrenaline, that are released into the body in response to stress, affecting various bodily functions and preparing an individual to face stressors.

Epinephrine

This entity, known as adrenaline, serves simultaneously as a hormone and a neurotransmitter, activating the body's defense mechanism known as fight-or-flight.

Norepinephrine

A neurotransmitter and hormone important in the body's fight or flight response, affecting heart rate, blood flow, and blood pressure among other functions.

Facially Expressed

Refers to the communication of emotions, intentions, or social information through facial movements and expressions.