Tina Is Training for a Biathlon

question 97

Multiple Choice

Tina is training for a biathlon. To train for the running portion of the race, she runs 14 miles each day, over the same course. The first 4 miles of the course is on level ground, while the last 10 miles is downhill. She runs 3 miles per hour slower on level ground than she runs downhill. If the complete course takes 1 hour, how fast does she run on the downhill part of the course?

• A) 18 mph
• B) 12 mph
• C) 9 mph
• D) 30 mph
• E) 15 mph

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Definitions:

Phospholipase C

An enzyme that plays a key role in cell signaling, breaking down phospholipids to generate second messengers like diacylglycerol and inositol triphosphate.

Second Messengers

Small molecules or ions that transmit signals from a receptor to a target inside the cell, facilitating intracellular communication.

DAG

Diacylglycerol, a lipid molecule that acts as a second messenger in signal transduction pathways within cells.

Signal Amplification

The process by which a few signaling molecules can elicit major responses in the cell; the strength of each signaling molecule is magnified.