Is this an independent variable or a dependent variable?

Question

1. The number of red blood cells in a mouse's blood at different levels of iron in its diet.

Answer 1

Since you are manipulating the amount of iron to see how it affects the number of red blood cells, the iron is the independent variable and the number of blood cells is the dependent variable.

Answer 2

Unfortunately that's actually a more complicated question than it is intended to be! However, the simple answer is that your example is supposed to demonstrate a DEPENDENT variable.

The concept of an independent and a dependent variable is that you adjust one, and you see the effect in the other. Imagine a light with a dimmer switch. If you adjust the position of the dimmer switch, you get different amounts of light from the lightbulb. You could graph this by measuring the position of the switch and measuring the light output with a light meter. The independent variable is typically represented along the horizontal axis, and in this case, it would be "dimmer switch position". The dependent variable is depicted along a vertial axis, and here it would be "light meter reading".

Blood cells contain iron, and to a degree, the production of red blood cells is dependent on the availability of iron. However, there are a couple of problems. For one, iron is stored in the body, and if dietary intake is low, the stored iron begins to be depleted. Because of storage, any fall in the production of red blood cells lags behind the fall in dietary intake, so an immediate effect is not seen (unless stores are chronically low). Another problem is that the blood cells continue to be made even if they are low in hemoglobin (which is actually what contains the iron). This is called iron deficiency anemia, and the main thing that is affected is the average amount of hemoglobin per red blood cell, NOT the number of red cells.

However, thats too much detail for here... I only have to include it because I hate sloppy questions! The intent of your question is that the number of red blood cells is a DEPENDENT value ralated to the amount of iron in the mouse's diet.

Answer 3

A dependent variable. The independent variable is the amount of iron you feed the mouse in the experiment.

Answer 4

the # of red blood cells is the Dependent variable. the level of iron is the independent variable. if you are making a graph, you should put te independent variable on the x-axis and the dependent one on the y-axis.

Answer 5

dependent the independent is the amount of iron given to the mouse