Why is the life span of white blood cells generally shorter than that of red blood cells?

Question

Even though white blood cells have a nucleus?

Answer 1

The life span of RBC is 120 days.

The life span of WBC is from a few hours to a few days to some years.

The span of a cell depends on the amount of function it performs.The function of RBC is to carry Haemoglobin. RBC has no organelle. It does not act for production of glucose nor  play any role in defence mechanism. it is not any energy producing.

White blood cells play a role in the defence mechanisms and need more energy. When active they die off soon. when passive they survive a few days longer.

neutrophil (non activated)- 24 hrs in blood , few (7-10)days in tissues

neutrophil active- less than 12 hrs

eosinophil and basophils - few hrs in blood when active and 8-12 days in tissues when not active

Life span of lymphocytes ranges from a few hours to a few Years depending on whether it is active or present inactive as a memory cell.

Intravascular lifespan of monocytes is 2-8 days...average half life is 3 days.

In tissues monocytes(now called macrophage) can stay longer upto 20 days.

Answer 2

It isn't that the life span of wbcs is shorter, but that most of your circulating wbcs are only in the blood for a few hours before moving into the tissues where they taks up a more permanent residence.  The blood is mostly a vehicle to get the cells from where they are produced (the bone marrow), to where they will live (various tisues).

Answer 3

The life span of white blood cells is from hours to years, depending on the body's needs. If you have an infection, lymphocytes kill the germs (or at least they try) and some of them secrete antibodies that attack the germs. So in an infection, the number of white blood cells increases and they die faster. Some of them remember that the germ was in your body and the remain in your blood stream for years so if the germ appears again, they attack it with much more efficiency.

Red blood cells do not live any longer than 120 days.