Question

mitochondria distribution
organ
heart, left ventricle
heart, left atrium
liver
pituitary gland
(approximate %)

1. sep interpret data what approximate percentage of cell volume in the mouse liver is composed of mitochondria?
2. sep use math approximately how much more cellular volume is composed of mitochondria in the left ventricle than in the pituitary gland?
3. sep construct explanations there are four chambers in the mouse heart, the right and left ventricles, and the right and left atria. based on the data given, which chamber, the left ventricle or left atrium, do you think pumps blood from the heart to the rest of the body? explain your answer.

Explanation:

Step1: Read liver mitochondria %

From the bar graph, the liver's mitochondria percentage is ~20%.

Step2: Calculate ventricle-pituitary difference

Left ventricle: ~50%, Pituitary gland: ~8%.
Difference: $50 - 8 = 42$

Step3: Analyze heart chamber function

Ventricles pump blood; higher mitochondria = more energy. Left ventricle has higher % than left atrium, so it pumps blood to the body.

Answer:

1. Approximately 20% of the mouse liver's cell volume is composed of mitochondria.
2. The left ventricle has approximately 42% more cellular volume composed of mitochondria than the pituitary gland.
3. The left ventricle pumps blood from the heart to the rest of the body. The left ventricle has a much higher percentage of mitochondria (≈50%) than the left atrium (≈35%), which means it has more energy-producing organelles to support the greater work required to pump blood throughout the entire body, while the atrium only needs to pump blood to the nearby ventricle.