Hormones
A runner's blood glucose rises after consuming a carbohydrate-rich meal. Which hormone helps lower blood glucose?
Insulin
Draw a model of cellular respiration using the names of the inputs and outputs.
Glucose + oxygen → carbon dioxide + water + usable energy (ATP)
A runner's body temperature reaches 40.1°C. The runner is at greater risk of what condition?
Hyperthermia
A red blood cell is placed in a hypertonic solution. What happens to the cell?
Shrinks
During a marathon, a runner’s body adjusts sweating, heart rate, and blood flow to help maintain stable internal conditions despite changes in the environment. This best describes __________.
Homeostasis
During a marathon, blood glucose falls below its normal range. Which hormone signals the liver to release glucose?
Glucagon
Which type of blood typically contains more carbon dioxide after passing through body tissues?
Venous blood
What is the process by which an organism maintains its internal body temperature within a safe, optimal range, regardless of external environmental changes?
Thermoregulation
A red blood cell is placed in a hypotonic solution. Water enters the cell, causing it to swell. What process moves the water across the cell membrane?
Osmosis
After a runner eats a meal, blood glucose rises, triggering insulin release. Insulin lowers blood glucose, which reduces the stimulus for further insulin release. This best describes a __________.
Feedback mechanism
When a runner’s blood glucose level drops during a marathon, the liver breaks down its stored form of glucose to help restore blood glucose levels. What is this stored molecule called?
Glycogen
The organ that releases insulin and glucagon to regulate blood glucose is the __________, while the organ that filters blood and regulates water balance by adjusting urine production is the __________.
Pancreas; kidney
Name three voluntary actions a runner could take to cool down after becoming overheated.
Stop running or slow down, Rest in a shaded area, Move to an air-conditioned location, Remove excess clothing, Drink cool water, Use a fan, Apply cool, wet towels, Pour cool water over the skin.
A runner’s red blood cell is placed in a solution where water moves into and out of the cell at equal rates, resulting in no net movement of water and no change in cell size. This best describes an __________.
Isotonic solution
What process regulates the body's water and solute concentrations to maintain appropriate internal conditions?
Osmoregulation
Which hormone signals the kidneys to conserve water when the body is dehydrated, causing a decrease in the volume of urine produced.
Antidiuretic hormone (ADH)
Which two body systems work together to deliver oxygen from the lungs to working muscles?
Respiratory and circulatory
Name three automatic body responses that help warm the body when its temperature falls too low.
Shivering, Goosebumps, Reduced sweating, Constriction of blood vessels near the skin.
A runner's blood sodium concentration becomes dangerously low. Water moves into brain cells, causing them to swell. What condition causes this swelling risk?
Hyponatremia
A well-hydrated runner has decreased ADH secretion. Will the runner produce a greater or smaller volume of urine?
Greater volume
Runner A has blood glucose of 48 mg/dL, Runner B has 92 mg/dL, and Runner C has 155 mg/dL. Which runner would be expected to release the most glucagon?
Runner A
Which part of the brain monitors body temperature and helps coordinate responses such as sweating and shivering?
Hypothalamus
Two runners exercise at 35°C. Runner P exercises in dry air, while Runner Q exercises in very humid air. Which runner can generally cool more effectively through sweat evaporation?
Runner P
A marathon runner drinks excessive amounts of water without replacing enough sodium. Water moves into brain cells, causing them to swell and increase pressure inside the skull. What type of solution is the runner’s blood relative to the brain cells?
Hypotonic solution
Four urine samples are observed: J = clear, K = yellow, L = dark yellow/amber, M = pale straw yellow. Which sample most strongly suggests water conservation due to increased ADH?
L (Because a large amount of water is pulled back into the body, the remaining waste products are excreted in a highly concentrated, low-volume urine, giving it a dark yellow or amber color.)