What do think are the number of
cells in the body of a Sumo wrestler? What do you think are the number of cells
in the body of a WWE wrestler? What do you think are the number of cells in the
body of Big Show? What do you think are the number of cells in the body of John
Cena?(both Show and Cena are WWE wrestlers with different body sizes)
The cell (from Latin cella,
meaning "small room") is the basic structural, functional, and
biological unit of all known living organisms. Cells are the smallest unit of
life that can replicate independently, and are often called the "building
blocks of life". The study of cells is called cell biology.
Cells consist of protoplasm
enclosed within a membrane, which contains many biomolecules such as proteins
and nucleic acids. Organisms can be classified as unicellular (consisting of a
single cell; including most bacteria) or multicellular (including plants and
animals). While the number of cells in plants and animals varies from species
to species, humans contain about 100 trillion (1014) cells. Most plant and
animal cells are visible only under the microscope, with dimensions between 1
and 100 micrometres.
The cell was discovered by Robert
Hooke in 1665. The cell theory, first developed in 1839 by Matthias Jakob
Schleiden and Theodor Schwann, states that all organisms are composed of one or
more cells, that all cells come from preexisting cells, that vital functions of
an organism occur within cells, and that all cells contain the hereditary
information necessary for regulating cell functions and for transmitting
information to the next generation of cells
A human cell has genetic material
contained in the cell nucleus (the nuclear genome) and in the mitochondria (the
mitochondrial genome). In humans the nuclear genome is divided into 46 linear
DNA molecules called chromosomes, including 22 homologous chromosome pairs and
a pair of sex chromosomes. The mitochondrial genome is a circular DNA molecule
distinct from the nuclear DNA. Although the mitochondrial DNA is very small
compared to nuclear chromosomes, it codes for 13 proteins involved in
mitochondrial energy production and specific tRNAs.
Cells form tissue, tissues form
organs, organs form organ systems and these systems come together to complete
the human body. The smallest unit of life, cells carry out the basic functions
of the body. Cells are bound by a membrane; the nucleus & organelles are
important components of cells.
Wikipedia says there are about
100 Trillion = 1014 of them(cells). You
can make a crude estimate, however, without counting all of them. Individual cells can be seen in a microscope
and you can measure their size, d, which is about 10 microns.
The volume of a cell is then d3 and its weight
is the volume times the density, close to that of water. Putting this all together you get that a
single cell has a mass around 10-12 kilograms.
Dividing into the weight of a good sized person, 100 Kg, you get the
Wiki-number.
Humans contain about 50 to 100
trillion cells. Most plant and animal cells are between 1 and 100 micron and
therefore are visible only under the microscope. Depending on the source, that
figure varies from 50 to 100 trillion cells. This number can vary, since the
cells are always dying off and then multiplying inside all the time.
howmanyarethere.us
Comments
Post a Comment