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  2. Human brain - Wikipedia

    en.wikipedia.org/wiki/Human_brain

    Betz cells are the largest cells (by size of cell body) in the nervous system. [40] The adult human brain is estimated to contain 86±8 billion neurons, with a roughly equal number (85±10 billion) of non-neuronal cells. [41] Out of these neurons, 16 billion (19%) are located in the cerebral cortex, and 69 billion (80%) are in the cerebellum ...

  3. Composition of the human body - Wikipedia

    en.wikipedia.org/wiki/Composition_of_the_human_body

    Parts-per-million cube of relative abundance by mass of elements in an average adult human body down to 1 ppm. About 99% of the mass of the human body is made up of six elements: oxygen, carbon, hydrogen, nitrogen, calcium, and phosphorus. Only about 0.85% is composed of another five elements: potassium, sulfur, sodium, chlorine, and magnesium ...

  4. Brain size - Wikipedia

    en.wikipedia.org/wiki/Brain_size

    The volume of the human brain has increased as humans have evolved (see Homininae), starting from about 600 cm 3 in Homo habilis up to 1680 cm 3 in Homo neanderthalensis, which was the hominid with the biggest brain size. [7] Some data suggest that the average brain size has decreased since then. [8]

  5. List of human cell types - Wikipedia

    en.wikipedia.org/wiki/List_of_human_cell_types

    The Human Cell Atlas project, which started in 2016, had as one of its goals to "catalog all cell types (for example, immune cells or brain cells) and sub-types in the human body". [13] By 2018, the Human Cell Atlas description based the project on the assumption that "our characterization of the hundreds of types and subtypes of cells in the ...

  6. Cell (biology) - Wikipedia

    en.wikipedia.org/wiki/Cell_(biology)

    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 ...

  7. Cell growth - Wikipedia

    en.wikipedia.org/wiki/Cell_growth

    Cell growth refers to an increase in the total mass of a cell, including both cytoplasmic, nuclear and organelle volume. [1] Cell growth occurs when the overall rate of cellular biosynthesis (production of biomolecules or anabolism) is greater than the overall rate of cellular degradation (the destruction of biomolecules via the proteasome, lysosome or autophagy, or catabolism).

  8. 50 Animals So Giant It’s Hard To Believe They’re ... - AOL

    www.aol.com/85-photos-animals-way-bigger...

    Fun fact: blue whales are 16 times bigger than a human. The post 50 Animals So Giant It’s Hard To Believe They’re Real (New Pics) first appeared on Bored Panda.

  9. Hayflick limit - Wikipedia

    en.wikipedia.org/wiki/Hayflick_limit

    The typical normal human fetal cell will divide between 50 and 70 times before experiencing senescence. As the cell divides, the telomeres on the ends of chromosomes shorten. The Hayflick limit is the limit on cell replication imposed by the shortening of telomeres with each division. This end stage is known as cellular senescence.